BIBLIOGRAPHY
SABIANO, JOHN PAUL L. APRIL 2006. Agronomic and Postharvest Characters
of Potato Entries for Ware and Seed Tubers in Calasipan, Atok, Benguet. Benguet State
University, La Trinidad, Benguet.
Adviser: Guerzon A. Payangdo, MSc.
ABSTRACT
Thirteen potato entries namely: 380579.3, 377852.1, 720071, 387039.15, 15.97.8,
381530.1, G.T, Alpha, Dejima, Ganza, Granola and Igorota were evaluated for their
growth and agronomic characters of potato entries grown in Calasipan, Atok, Benguet
from May 2005 to February 2006 to determine entries suited for table seed, and
processing purposes.
Significant differences among thirteen potato entries were found for plant vigor,
plant survival, pest and diseases incidence, number and weight of marketable and non-
marketable tubers, computed yield per hectare, dry matter content while percentage
weight loss, degree of greening and number of sprouts were not significantly different
among the entries evaluated.
Despite of typhoon damages during their growth, Ganza and 387039.15 produced
the highest marketable yield with low pest and disease infection. Entries 377852.1 and
G.T produced the low marketable yield. This result could be a basis of recommendation
for planting under Calasipan Atok, Benguet condition during the wet season.

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Furthermore, stored tubers from the different potato entries showed no defects nor
decay during the four months of storage. Sprouting is visible among the thirteen entries
during the first week. Igorota had the highest percentage weight loss and 285378.27 had
the lowest weight loss. Greening was visible in the different entries but minimal in entries
with violet-skinned.

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TABLE OF CONTENTS


Page
Bibliography. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
i
Abstract . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
i
Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
iii


INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1
REVIEW OF LITERATURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3
MATERIALS AND METHODS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
14
RESULTS AND DISCUSSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
24

Climatic Condition During the Study Period . . . . . . . . . . . . . . . . . . . . . . . .
24

Growth Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
25

Plant Vigor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
25

Plant Survival . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
28
Reaction to Leafminer and Lateblight . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
28
Yield and Postharvest Characters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
29
Number and Weight of Marketable Tubers . . . . . . . . . . . . . . . . . . . . . . . . .
29

Weight of Marketable Potato Tubers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
29

Number of Non-marketable Tubers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
31

Weight of Non-Marketable Tubers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
31

Computed Yield Per Hectare . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
34
Tubers Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
35
Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
37
iii

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Degree of Greening . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
37

Degree of Decay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
40

Percentage Weight Loss . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
40
Number of Sprouts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
41
Dry Matter Content. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
41

Sensory Evaluation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
32

Chipping Quality. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
44
SUMMARY, CONCLUSION AND RECOMMENDATION . . . . . . . . . . . . . . .
47
Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
47
Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
49
Recommendation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
50
LITERATURE CITED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
51
APPENDICES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
54

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INTRODUCTION


Potato
(Solanum tuberosum L.) is one of the major vegetable crops in Benguet. It
is mainly grown for its tubers due to its varied uses such as food. The crop has good
market prospect, but potato producers are often troubled by several problems such as the
production of quality tubers accepted in the market (Sano, 1977).

With the insufficient supply of certified potato seed tubers and the high cost of
imported seeds, majority of low income farmers depends on their potato seeds obtained
from previous cropping. Generally, the yield capacity and quality of the planting
materials are not considered. Nevertheless, this problem could be solved with the use of
stem cuttings to provide clean seed tubers of potato (Dalang, 1986). As a means of
obtaining clean planting materials and increasing yield, potatoes varieties, Dalisay and
Montañosa developed at Benguet State University were evaluated using stem cuttings.
Stem cuttings from Granola, Igorota and Montañosa were found feasible as source of
planting materials aside from the use of seed tubers.

The increasing population growth of our country demand for more food and
energy sources. Local growers barrel these increasing demand until sufficiently surplus
the demand for table purpose. However, there is low production which is attributed with
the use of traditionally produced seed tubers.

The fast expansion of processing companies in the country also command
production of the processing type varieties. In lieu of the unsustained supply, these
manufacturing companies continue importing billion worth of pre-processed potatoes.
These amount could have been saved if only the country adequately give due attention to
these demand.
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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A number of processing and table potato varieties are available at BSU-
NPRCRTC. However, evaluation of these varieties be a continuing activity. Evaluating
other potential clones and varieties in different locations is vital to determine their
performance under different soil, temperature and elevation conditions. This will also
guide farmers especially in Atok to select adopted varieties. Production of the desired
potatoes will also help the farmers market their produce, the consumer and processors to
avail of locally produce varieties, boost the locally potato industry, and change the
mentality of the importers who claimed that Benguet produce are of poor quality.

Apart from the problem of low yield, the potato growers also lacks knowledge on
proper seed storage. Their storage techniques for seed tubers are poorly done by packing
them in sacks for two to three months. These results to severe sprouting, utilizing the
food reserves that should be used for establishing new healthy shoots.

Continuous varietal development should be done to cope up with genetic
degeneration caused by pests and diseases.

The study aimed to: evaluate the growth and agronomic characters of potato
entries grown in Calasipan, Atok, Benguet and determine entries suited for table potato
and seed tubers; and processing.

This study was conducted at Calasipan, Atok, Benguet from the month of May
2005 to January 2006.




Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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3
REVIEW OF LITERATURE


Background of the Potato Industry

Eighteen of the largest potato producers grow nearly 90% of the world’s
production since 1961. However, an estimated 60% of potato production in developing
countries is for human consumption, 15% for fee, 10% for seed, 5% for processing and
about 10% is lost to waste (Hampson, 1987).

In the tropics, potato performs one of four different functions in the human diet
serving as a basic staple, complementary vegetables, seasonal vegetable, on delicacy to
be consumed on special occasion (Poats, 1983).

In Peru and Bolivia, potato is traditionally grown for human consumption and
typical potato is solar dried (Yamamoto, 1987).

The potato is relatively a costly commodity especially in most developing
countries (Gitomer, 1987). When value is added to potato through transformation, the
resulting product is either prohibitively expensive for all but the highest income
households or simply cannot compete with cheaper substitutes in industrial uses (Gomez
and Wong, 1989).

Morphology of the Potato Tubers

The morphological characteristics of potato differs. The shape may range from
compressed or ovate to elongate. Also the depth of eyes may range from protruding to
very deep. Together with the flesh is one of the main basis in selecting or rejecting a
variety. In tuber skin type, majority of potato varieties have smooth skin but some may
have rough or even netted skin (Zamora, 1994).
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
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Importance of Varietal Evaluation

According to HARRDEC (1996), the first decision in planting is to know the best
variety of plant. To achieve maximum production, the best variety that is adapted to the
locality should be selected. Excellent cultural management practices may not determine
the best suited variety, a series of a varietal evaluations must can be conducted to
determine the performance of anew or previously untried variety.

In 1990, Sunil stated that varietal evaluation is a process in plant breeding, which
provides comparison of promising lies developed by breeders. It is through varietal
evaluation that a breeder select the best performing variety among developed lines terms
of yield, quality, adaptability, stress, tolerance and resistance to pest and disease.
Furthermore, selecting the right variety farmer may initially accept a new variety that will
suit in his/her farm, thus minimize problems associated with water and fertilizer
management. The variety to be selected should be high yielding, pest and disease
resistant and hence, ensure more profit.

Harvesting

In Atok, harvesting is preferably done early in the morning. Harvesting is done
manually using spading forks, or loosening hoe for exposing the tubers. Digging of tubers
could be done in loose friable soils.

Care in harvesting is necessary to avoid skinning, cuts, cracks and bruises that
may serve as an entry points for the tuber month and other pest (Ganga, 1996).

Furthermore, in 1980, Balaoing stated that three months after planting, the crop is
ready for harvest. This time, 70 – 75 percent of the foliage would have turned to pale
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
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5
yellow and dry indicating maturity of the crop. Matured tubers peel off readily. The time
of harvest is when the temperature is cool and less humid and the soil is dry.

Postharvest Handling and Practices

Sinclair (2000) stated that postharvest is concerned with the harvesting treatment,
handling, storage, distribution and marketing of potatoes. It is not simply concerned in
maintaining the quality of the produce but is also considers maximum income for the
producer or trader income generation is a vitally important role of postharvest
horticulture. Other important considerations include meeting the nutritional and casthetic
requirement of human beings and minimizing waste. Also insuring that quality loss
between harvest and consumption is minimal.

Sorting and grading are classified according to size and grade; large, big, medium,
small and marbles. Cabal (1996) said that exact size range within any grades varies from
farmer to farmers. If the supply is low, the farmer lowers the base limit to each size.

Furthermore after grading potatoes are packed into red bags, plastic, or thick-
laced bamboo basket. Red bags (25-32 kg capacity) are the most suitable packing
materials.

In 1983 Estalin stated that the grade of the commodity describes its quality as
procured by the consumers or the exporter. The grade tells the marketing men if the
produce can withstand storage or whenever it has to be released immediately to the
marketing area. Grades also provides a basis for a division of price at any point in the
market.


Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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Criteria for Seed Tubers of Potatoes

Leopold (1975) stated that during the development of the tubers on the plant, the
buds on the eyes of the tubers successively become dormant, starting at the stem end. The
apical eye is the last to become dormant. At the end of the dormancy period, the eyes
again sprout. It the tubers are placed under appropriate temperature conditions, one or
more sprouts form in each tuber.

The rate of growth of the sprout after the seed potato has been planted is directly
correlated with the length and nature of the sprout at the time of planting, also the
conditions during the growth temperature, and other storage conditions-influence the
growth rate and the are thus very important.

Varieties in which the vines develop rapidly, those with second growth and those
drought resistant often have a short dormant period. Krijthe, as cited by Smith (1977),
found no correlation with early maturity or starch content. Maturity or tubers at harvest is
important in determining length of the dormant period. Growing conditions such as soil,
fertilizers, and climatic factors such as rainfall cause differences in length of dormant
period between lots of the same variety and between the different years. Weight of
sprouts increase with age f tubers as a result of sprout growth and an increase in the
number of sprouts per tuber. The increase in the number of sprouts is a result of
decreasing dominance of apical growing point of the tuber. When the apex of the sprout
becomes inactive or damaged, branching results.

As number of stems increases, the number of tuber formed also increases, and
average size of tubers is likely to decrease. Some varieties produce many stems and
consequently a high proportion of small tubers. Sprouted seeds of such varieties with
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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7
only one or two sprouts per seed piece result in a crop with a higher proportion of large
potatoes. Toosey (1958) reported that one variety produced on average of 9.5 stems and
45.7 tubers per plant, few of them of marketable size. When all but sprout were removed
before planting, an average of 20.5 tubers per plant were produced, many of sellable size.
When seed pieces were restricted to one stem, the number of tubers was reduced and a
high proportion of large tubers were formed.

Toosey (1958) found out that seed stored under warm conditions soon after
harvest produced few sprouts. The seed was still in the single sprouting phase when the
heat induced it to sprout. Without artificial heat, sprout growth was low and seed pieces
averaged 5 to 7 sprouts each. De-sprouted seed further increased number of sprouts per
seed piece. The larger the seed pieces, the greater the number of sprouts per seed piece.

Baldwin (1963) found in England that yields from sprouted seed in general were
higher than those from unsprouted seeds. Placing fertilizer partly in contact with seed
pieces had no serious effect on unsprouted seeds but depressed the yields from sprouted
seeds.

The number and size of tubers produced are affected by sprouting treatment, seed
size and spacing, early sprouting results in fewer sprouts per seed piece and fewer plants
per hill than late sprouting. The number of tubers produced is directly related to tuber
numbers (Toosey, 1958). Early sprouting, small seed, and wide spacing increase tuber
size, but early sprouted seed planted closely gave higher yields than late sprouted seed
planted farther apart. Burghausen (1962) as cited by Smith (1977) also noted that
acceleration of sprout development reduces the interval between planting and emergence.
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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The period of productive growth is prolonged and maturity is advanced. There were
fewer missing hills and growth of planting was more uniform throughout the field.

Sprout growth during storage is related linearly to the amount of available tuber
substrate. Light intensity and day length influence sprout growth very little, temperature
variety are much more important. Increase in sprout size at planting time results in earlier
emergence and tuber initiation, and the relative rate of plant growth is reduced (Headford,
1962). Temperature and light are the principal weather factors which modify tuber
initiation and growth; photo-period is relatively unimportant (Headford, 1962). Pre-
germination of tubers results in a greater development of the root system and a higher
proportion of root to top than those not pre-sprouted. Early varieties react more in this
manner than those late ones (Birecki and Roztropowicz, 1962).

Sprouting seed potatoes before planting results in early growth of the plants and
usually increases the yield. The form of growth of the tops and the production of stolons
and tubers is related to the number of sprouts developed before planting. Removal of
some or all of the sprouts before planting may have a marked effect on growth and
production of the plant. All varieties do not react to similar conditions in the same way.

Beukemia and Zaag, 1970 stated that the effect of storage on the growth and yield
of potato is a important factor to consider it higher yield is desired. On the other hand,
Estalin (1983), found out that full gown seeds planted after five months of storage
produced higher yield of marketable sized potatoes.

Criteria for the Table Potatoes

In 2004 Edward mentioned that 3,508 acres of potatoes were grown for the fresh
market. The most popular variety grown was the Russet Norkotah, followed by the Red
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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9
Norland and then the Russet Burbank. Other popular varieties grown are Ranger Russet,
Bintje and Sangre. Gournet and specially varieties are also grown for fresh market sales.
The main factors of table potatoes are texture, color, flavor and smell.

Furthermore white or yellow-fleshed potatoes will have a creamy colour and
should not discolour after cooking. Potatoes when cooked should smell like a normal
cooked potato. Potatoes that have green colour on the surface should be peeled and
remove all the green skin. Small amount are okay to eat but may add bitterness to the
taste of the potato. Pre-peeled potatoes are also available for the food service industry.
They re vacuum-sealed and must be refrigerated, they have a limited shelf-life. Table
potatoes are marketed through potato packing facilities, where they are washed, graded
and delivered to the wholesale and retail costumer. Fresh potatoes will be a welcome
additional breakfast, lunch or dinner.

Potatoes are fully developed when the tops die naturally. A mature potato tuber
has a firm skin and solid flesh. Immaturity in potatoes is shown by feathering, or peeling
of the skin. This defect is usually accompanied by scalds (brownish discolorations),
which are really injuries to the exposed flesh. Potatoes posses the best table quality when
they are well matured (Edward, 2004).

Martin (2006) stated that sunburned tubers (greened by light) should be discarded
in favor of those with normal coloring. The normal skin of the potato variety shows a
light golden-green translucence, potatoes with enlarged lenticels and other skin defects
should not be remove. Purity of variety - the tuber characteristics of the variety should be
true in all respects. Some points to consider are shape: size, color of skin, color of flesh
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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and eyes, depth and placement of eyes, prominence and correctness of eyebrows, netting,
smoothness and any other feature listed in the official description.

Potatoes are also classified as early, mid-season on late, to describe their maturity.
There are minor modifications of these terms. General appearance – samples should have
a bright, clean, smooth, attractive appearance. Care should be taken that the natural color
and bloom of the skin are not destroyed by excessive rubbing or brushing. “Bright”
describes potatoes that are free from dirt, or other foreign matter, damage or discoloration
from any cause (Martin, 2006).

Important Criteria for Processing
Chips and Tuber Characteristics


Shallow eyes, round or elongated tuber shape, smooth skin, and freedom from
defects are among the external characteristics of potatoes preferred by the processors.
These characteristics are important for lesser trimmings (Ludwig, 1985), the preferred
sizes for high chip yield, the absence of discoloration or browning during frying, to give
uniform yellow to light brown chips, and good quality for food safety. Diseased tubers
(i.e. bacterial wilt) when chipped exhibit rings of worn color that is unfit for food.
Preliminary studies of BSU showed that bacterial wilt infected tuber causes allergenic
reactions especially to susceptible individuals.

Another important processing criteria is the dry matter content that finally affects
the frying quality. Ideally, processing potatoes should have at least 21% and above dry
matter. Lower percentage dry matter gave soggy and less crispy chips. Thus, could be
used for other food products such as salad, creamed potatoes, breads, cookies, candies ad
as ingredient to vegetable dishes (Raceris, 1959).
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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In 1985 Ludwig mentioned that specific gravity and dry matter content are related
and that they greatly influence the cooking quality. When their values are higher, the
output of the frying process is also higher and up take of oil is lower.

A very low sugar content is apparently important to prevent darkening of chips.
Quality wise, sugar content should be below 2%. Potatoes of low sugar content result in
lighter color chips (Smith, 1977).

Greening of Potatoes

Greening in potatoes indicates an increase solanine levels. Greening is the result
of exposure to light and this can occur in potato storage cellars, in the store shelf and at
home on the counter. The green color is caused by the presence of chlorophyll. This is a
natural plant pigment which is tasteless and harmless. The tendency toward greening
differs among potato varieties. This varietal difference has been found toe specially
significant when potatoes are exposed to the artificial light found in retail stores,
including storage and sales areas (Vandre, 2003).

Sinden (1992) stated that steroid alkaloids (solanine and chaconine) are present in
all potato tubers as a process product. There are no reports of ill effects from consuming
potatoes that have normal levels of these potentially toxic compounds. Solanine will only
be toxic to human when solanine content rise from 20 mg/100g fresh weight.

Smith (1977) stated that greening is caused by the exposure of tubers to natural
or artificial light in the field, transit, or in the storage. The green colored tissue is usually
accompanied by the formation of solanine, an alkaloid that my be poisonous if consumed
in sufficient amount.

Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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Storage of Potatoes

Rastovski (2003) stated that storage is necessary for a continuous supply to the
market of fresh potatoes. This means that part of the crop must be stored from 8-10
months. The demands for steady supply of potatoes increased ever since potato has been
used for industrial processing.

Baldasan (1980) observed that dark condition enhanced shorter dormancy period
of tubers and pointed out that the size of tuber sprouted was significantly affected by the
storage condition and not by the varietal nature of tubers. Tubers sprouted under dark
storage condition were etiolated with long unhealthy slender stem, and with small leaves.

Packaging/Transportation of Potatoes

Packaging is designed for promotions and product placement to make a product
attractive to consumers. Packaging includes any materials used by the consumer to
transport the goods to be sold (Sinclair, 2000). Ratstovski (1981) also stated that the
quality of potatoes must be maintained in the packaging containers like fiber board, crates
and Styrofoam. The packaging must afford adequate ventilation. The respiration of the
tubers are eliminated and fresh air (oxygen) is supplied.

Marketing of Potato Tubers

USDA (1992) stated that quality is of paramount importance to market
acceptance. The fresh market appearance of potato tubers strongly influence sales color,
size, shape and defects shape consumer’s first impression of quality. Texture, flavor, and
nutritive value are less obvious but still important quality components. Jimenez (2000)
also stated that specially potato varieties with range in yield potential, tuber size
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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distribution, maturity, and flesh color intensity is available for conventional and
alternative marketing system. Consumer evaluations indicates a widely variable
preference in color, taste, texture and other quality parameters.

Fresh potato tubers pass through agents, assemblers, wholesalers, Financier-
whosaler, wholesaler-retailers to consumers. Processing firms procure their raw materials
directly from farmers or farmers group or through an agent or middlemen. In 1992,
Mercado stated that the farmer problems on vegetables industries are inadequate
transportation facilities, absence of reliable price information and lack of merchandizing
techniques where these results to wastage and poor quality of farm produce. These
problems were also the cause of high marketing cost and low price for farmers but high
price for the consumers.













Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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MATERIALS AND METHODS


The study was planted and stored during the wet season from May to December
2004.

An area of 390 square meters was thoroughly prepared and divided in three equal
parts which accommodated the thirteen treatments with three replications. Each plot
measured 1m x 10m. The treatments were laid out following the randomized complete
block design (RCBD). The organic fertilizer was applied as basal fertilizer after land
preparation. Triple 16 NPK inorganic fertilizer as supplemental was applied during
hilling-up. The pre-sprouted potato tubelets from the different entries were planted at one
tuberlet per hill, distanced of 25 cm x 30 cm between hills and rows. After which all the
necessary cultural management practices for potato seed production such as weeding,
pest control and hilling up were strictly employed.
The pre-harvest and post harvest data such as plant vigor, plant survival, pest and
disease incidence, yield components, postharvest characteristics, and sensory evaluation
of boiled and chip products were taken aside from other related observations.

Newly harvested potato tubers obtained from the different accessions were
weighed (1 kg) per treatment and per replication. The tubers were displayed in a diffused
light condition for four months. Each accession served as the treatment, and were
replicated three times following the completely randomized design (CRD).

All other cultural practices required in potato production such as weeding, pest
control, irrigation and hilling-up were strictly employed throughout the growing season.


Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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Treatments were the following:




Accession
Source

V1
- 380579.3
CIP
-
Peru

V2
- 377852.1
CIP
-
Peru

V3
- 720071 CIP
-
Peru

V4
- 387039.15
CIP
-
Peru

V5
- 285378.27
CIP
-
Peru

V6
- 15.97.8 CIP
-
Peru

V7
- 381530.1
CIP
-
Peru

V8

-
G. T.


Korea

V9

-
Alpha


USA

V10

-
Dejima


Japan

V11

-
Ganza


CIP-Peru

V12
- Granola**
Germany

V13
- Igorota
**
Philippines
(NPRCRTC)
** check variety
Data gathered:
A. Growth Performance

1. Plant vigor. This was obtained through visual observation using the rating scale
of 1-5 taken starting at one month after planting and until two and half months (Palomar
and Sanico, 1994).
Scale
Description
5

Highly
vigorous
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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16
3 Moderately
vigorous
1 Very
poor
vigor
2. Plant survival. This was obtained one month after planting using the formula:
No.
of
Plants
Survived
% Survival
= -------------------------------------------- x 100



Total No. of Plants Planted


3. Pest and diseases incidence. This was obtained using the following rating scale
of CIP (2000).

a. Insect (leaf miner)
Scale
Description


Remarks
1 No
infection
Highly
resistance
2

1-20% leaf surface infected
Resistance
3

21-40% leaf surface infected
Moderately resistance
4

41-60% leaf surface infected
Moderate Susceptible
5 Heavily
damaged
with 81%
Susceptible
leaf
surface
infected



b.
Disease
(blight). This was taken by using the following scale of Potato
International Center (2000) and Highland Technoguide Potato (Henfling, 1982).
Blight CIP
Scale Description of Corresponding Symptoms (Henfling, 1984)

1
1
No blight were seen.

0.1-1
1
Very few plants in larger plants with lesions, not more than 2
lesion per 10 m of row (11-30 plants).

1.1-2
2
Up to small lesions per plant.

3.1-10
3
Up to 30 small lesions per plant or up to 1in each 20 leaflet
attached.

10.1-24
4
Most plant are visibly attached and 1 and 3 leaflets infected few
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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17
multiple infections per leaflets.

25-29
5
Nearly every leaflets with lesions multiple infections per leaflets
are common. Field or plot green, but all plants in pots are blighted.

50-74
6
Every plant blighted and half the leaf area destroyed by blight.
Plots looks green freckled ad brown, blight is very obvious.

75-90
7
AS previous but ¾ of each plant blighted lower branches maybe
overwhelming killed off and the only green leaves, if any are top
of the plant shade of plants maybe more spindly due to extensive
foliage loss. Plot looks neither brown nor green.
91-97
8
Some leaves and most stem are green plot looks brown with some
green patches.

97.1-99.9
9
Few green leaves almost blight lesions remains many stem lesions
plot look brown.

100.0
10
All leaves and stem dead.


c. Early blight incidence
Scale
Description


Remarks
1 No
infection
Highly
resistance

2

1-25% of the plant infected
Resistance

3

26-50% of the plant infected
Moderately resistance
4

51-70% of the plant infected
Moderate Susceptible
5

76-100% of the plant infected
Susceptible

B. Yield and Postharvest Characters

1. Number and weight of marketable tubers per plot (kg). Tubers of marketable
quality from small to large was weighed after harvest and recorded.

2. Number and weight of non-marketable tubers per plot (kg). All tubers which
are less than 10 grams with defects such as malformed, cuts, cracks, and 10% greening
was considered as non-marketable.
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
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18

3. Computed yield per hectare (tons). This was computed by using the formula
(Palomar and Talatala Sanico, 1994).



Yield (t/ha) = Yield (kg)/plot x 1.28205






4. Tuber characteristics. Characterization of tubers were done from yield of ten
sample plants per plot at 99 days after planting (DAP). Characterization involved the
following (NPRCRTC, 2003).

a. Tuber shape. This was described by visual observation.
Scale
Description
1
Round
2
Ovate
3
Oblong
4
Elliptic
5
Long/elongate
b. Tuber size. This was obtained through visual observation of the size, diameter
and weight.
Scale

Size
Diameter
(cm)
Weight
7 Large
6.1
and
above
60g
and
above
5


Medium
4.5 – 6.0

15 – 25g
3 Small
3.0
and
below
5
–
10g
c. Skin texture. This was recorded using the description listed below:
Scale
Description
1
Smooth
2
Moderately smooth
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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19
3
Very smooth
4
Rough
5
Very rough
d. Depth of eyes. This was recorded by using the description listed below:
Scale
Description
1
Shallow


3


Deep
5 Moderate

e. Skin color. This was described by visual observation.
Scale
Description


1


Yellow
2 Pale
yellow
3 Dark
yellow

f. Tuber flesh color. This was described by visual observation.
Scale
Description
1
Yellow
2
White
3
Cream
C. Storage
1. Degree of greening. This was taken every 15 days based on surface area using
the rating scale (Salda, 2003).
Scale
Description
1
No greening
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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20
2
1-5% greened surface area
3
6-10% greened surface area
4
11% and above greened surface area
2. Degree of decay. This was taken every after 15 days intervals using the rating
scale (Bayogan, 1986).
Scale
Description
1
No decay
2
1 – 19% decay/rotting of tubers surface area
3
20 – 49% decay/rotting of tubers surface area
4
50 – 79% decay/rotting of tubers surface area
5
80% and above decay/rotting of tubers surface area
3. Percentage weight loss. The tubers were weighed every after 7 intervals for
one month and computed using the formula.


Initial Weight – Final Weight
% Weight Loss = ------------------------------------------- x 100
Initial
Weight
4. Number of sprouts per tuber. The number of sprouts per tuber was counted at
the end of the experiment.
D. Eating Qualities of Boiled Potatoes

This were taken by using the rating scale of NPRTRTC (2003) in terms of
appearance, color, flavor, texture, general acceptability.
E. Processing Qualities
a. Dry matter content. This was taken by oven method using 30 grams of sliced
potatoes from 3 tubers per replicate per variety.
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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21


Fresh Weight – Oven Weight
% Moisture = --------------------------------------- x 100
Fresh
Weight


% DMC = 100% - % MC
b. Chipping quality. Chipping quality was assed using the processing scheme

of the NPRCRTC (2003) as follows.


Tuber

Peel thinly
Slice at 1-2 mm
Wash remove starch at cuter surface
Drain and wipe with clean cloth to remove moisture
Deep fry using coconut oil (palm oil)
Drain and pack for sensory evaluation

The potato chips were evaluated as to the degree of browning of chips, %
recovery and sensory evaluation of chips.

The degree of browning was evaluated using the rating scale of 1-4, as:
Scale
Description
1
Severe browning (6% browning)
2
Moderate browning (3-5% browning)
3
Slight browning (1-2% browning)
4
No browning (0% browning)


Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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22
The % recovery was taken by getting the initial weight of tubers processed into
chips and the final chips yield. These were based on the following:
a. Weight of whole tubers
b. Peeling/trimming loss
c. Weight of peeled tubers
d. Weight of chips
The sensory test was done by 10 panelists composed of students and faculty.
a. Crispiness description and acceptability (Hedonic scale)
Scale
Remarks
1
Extremely crispy
2
Very crispy
3
Moderately crispy
4
Slightly crispy
5
Soggy/not crispy
b. Oiliness description and acceptability (Hedonic scale)
Scale
Remarks
1 Extremely
oily
2 Oily
3 Moderately
oily
4 Slightly
oily
5 Hot
oily/too
dry


Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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23
c. Flavor acceptability (hedonic scale)
Scale
Remarks
1
Very strong potato flavor
2
Strong potato flavor
3
Little potato flavor
4
Very little potato flavor
5
No potato flavor
d. General acceptability
Scale
Remarks
6
Like extremely
5

Like very much
4

Like much
3

Like moderately
2

Like slightly
1

Not like/dislike






Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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RESULTS AND DISCUSSION

Climatic Condition During the Study Period

Air temperature, relative humidity, rainfall and total sunshine from May to
February 2006 are presented in Table 1. Minimum air temperature ranged from 10.10-
14.80oC while maximum air temperature is from 19.2-22.80oC. Mean relative humidity
and rainfall recorded were 88.1% and 3.42mm, respectively. Total sunshine ranges from
110.35 to 498.10cm with a mean of 327.12.

According to HARRDEC (1996) potato grows best in areas with temperature
ranging from 17-22oC and average relative humidity of 86%. At lower light intensity,
haulm growth is stimulated and tuber formation may be delayed. Likewise, lower light
intensity enhances the effect of long day length delaying tuberization and promoting
canopy growth. However, these meteorological parameters may vary depending on the
adaptation of the entries.

Table 1. Climatic data during the study period
MONTH AIR
TEMPERATURE
RELATIVE RAINFALL TOTAL
Minimum
Maximum
HUMIDITY
(mm)
SUNSHINE

(%) (cm)
May
14.80 22.80 95.00 6.80 438.20
June
13.20 21.70 94.00 6.90 498.10
July
13.40 21.00 90.00 5.50 438.10
August 13.30 21.70 94.00 5.10 460.50
September 12.40 20.10 90.00 4.20 396.70
October 12.10 20.30 91.00 2.80 387.00
November 12.20 21.50 85.00 2.00 317.40
December 11.30 20.30 79.00 1.30 111.90
January 10.50 20.10 82.00 0.04 113.00
February 10.10 19.20 81.00 70.05 110.35
Mean
26.9 26.9 88.11 3.42 3.27.12

Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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25
Growth Performance


Plant Vigor


Table 2 and Fig. 1 shows the plant vigor at 30 and 60 DAP, where entries
380579.3, 387039.15, 285378.27, 15.97.8, 381530.1, Ganza, Granola and Igorota
exhibited highly vigorous rating while entries Alpha, Dejima, 377852.1, 720071 and G.T
gave moderately vigorous.

Ideally, potato plants should have vigorous growth for better yield. In this study,
however, the vigor rating effect to yield, eating and chipping qualities depend on the
varieties.

Fig. 2 and 3 shows the overview of the field before and after harvest.

Table 2. Plant vigor at 30 DAP and 60 DAP of thirteen potato entries evaluated

ENTRY PLANT
VIGOR
30 DAP
60 DAP
380579.3
Highly vigorous
Highly vigorous
377852.1
Moderately vigorous
Moderately vigorous
720071
Moderately vigorous
Moderately vigorous
387039.15
Highly vigorous
Highly vigorous
28537827
Highly vigorous
Highly vigorous
15.97.8
Highly vigorous
Highly vigorous
381530.1
Highly vigorous
Highly vigorous
G.T
Moderately vigorous
Moderately vigorous
Alpha
Moderately vigorous
Moderately vigorous
Dejima
Moderately vigorous
Moderately vigorous
Ganza
Highly vigorous
Highly vigorous
Granola** Highly
vigorous Highly
vigorous
Igorota** Highly
vigorous Highly
vigorous



** Check variety





Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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26





















A.





















B.

Figure 1. Overview of the field at (A) 45 DAP (B) 75 DAP


Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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27




















Figure 2. Overview of the field before harvest





















Figure 3. Overview of the field at harvest




Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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28
Table 3. Plant survival of thirteen potato entries evaluated at 45 DAP

ENTRY


SURVIVAL
(%)
380579.3

97ab
377852.1

95b
720071

83c
387039.15

98a
28537827

97ab
15.97.8

97ab
381530.1

98a
G.T
83c
Alpha
85c
Dejima

83c
Ganza
98a
Granola**

95b
Igorota**

97ab
CV (%)


1.64
Means with the same letter are not significantly different by DMRT (P>0.05).

Plant Survival


Potato entries with 98% plant survival at 45 DAP were 387039.15, 381530.1 and
the new variety released Ganza. These were followed by 380579.3, 285348.27, 15.97.8,
anther check variety Igorota, Granola, and 377852.1 with 97% and 95% plant survival,
respectively the rest had poor survival rater at 83% to 85%. The varied percentages could
be due to genetic differences where some varieties easily establish growth and tolerate
wet condition while others are susceptible.

Reaction to Leafminer and Late Blight
Leafminer and late blight incidence at 45 DAP in Table 4 reveals that majority of
the potato entries were highly resistant except for entries Alpha, G.T and Dejima that
were rated only as resistant. The low infection may be attributed to minimal spraying of
insecticide and fungicides.
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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29
Table 4. Reaction to leafminer and late blight of thirteen potato entries evaluated at 45
DAP

ENTRY PEST
DISEASE
(leafminer)
(late blight)
380579.3 Highly
resistance

Highly resistance
377852.1
Highly resistance
Highly resistance
720071
Highly resistance
Highly resistance
387039.15
Highly resistance
Highly resistance
28537827
Highly resistance
Highly resistance
15.97.8
Highly resistance
Highly resistance
381530.1
Highly resistance
Highly resistance
G.T Resistance
Resistance
Alpha
Resistance
Resistance
Dejima Resistance Resistance
Ganza Highly
resistance Highly
resistance
Granola** Highly
resistance Highly
resistance
Igorota** Highly
resistance Highly
resistance


These low leaf miner infestation and late blight infection may be attributed by
minimal spraying of fungicides.

Yield and Postharvest Characters


Number and Weight of Marketable Tubers

The number and weight of marketable tubers indicates high economic returns in
potato production (Fig. 4).
As per number and weight of marketable tubers classified as super extra large
(SXL), extra big (XL), and medium entries 387039.15 and Ganza are preferred for
processing and table purposes. These data were obtained despite of the typhoons that
affected the crop during its growth.
Super XL classification come from entries 387039.15 and Ganza. The rest were
comparable with 380579.3, 285378.27, 381530.1, Granola and Igorota.
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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30
Table 5. Number and weight of marketable tubers of thirteen potato entries evaluated (10
sq. m)

ENTRY NUMBER
WEIGHT
Super XL
Extra Big Medium Super XL Extra Big Medium
(60g and
(26-59g)
(15-25g)
(60g and
(26-59g)
(15-25g)
above)
above)
380579.3 19b 30b 112c 155b 1.67b 2.28cd
377852.1 7b 12c 45d 0.58b 0.67b 0.47e
720071 8b 15c 63cd 2.48b 0.65b 0.88e
387039.15 76a 92a 191b 7.00a 4.88a 5.03a
28537827 18b 40b 244a 1.12b 1.52b 3.92b
15.97.8 17b 29b 110c 1.30b 1.15b 1.60cde
381530.1 16b 23b 73cd 1.02b 0.80b 1.07e
G.T 8b 15b 30d 0.68b 0.55b 0.58e
Alpha 9b 16b 53d 0.72b 0.73b 1.30de
Dejima 9b 17b 63cd 0.60b 0.65b 0.98e
Ganza 64a 73a 107c 5.83b 3.53a 2.52c
Granola** 14b 21b 68d 0.88b 0.85b 1.43de
Igorota** 19b 32b 75d 1.53b 1.13b 1.57cde
CV (%)
26.96
29.72
29.32
21.83
22.97
24.00
Means with the same letter are not significantly different by DMRT (P>0.05).

For the extra big size, entries 37039.15 and Ganza still had the significantly of 92
and 76. Entries 285378.27, Igorota and 380579.2 give comparable number to the rest
except 377852.1 and 720071 that had the lowest number.
The highly significant numerous number of classified medium size tubers came
from entry 285378.27, followed by the prolific 387039.15. The lowest came from the
other entries led by G.T entry.
In terms of weight, entry 387839.15 followed the same trend having the heaviest
weight. It’s super XL weighed 7.00 kg. per 10 m2 plot. This was followed by variety
Ganza with 5.83 kg. These two entries similarly gave the highest weight of extra big
tubers.
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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31
This difference in terms of weight could be due to their outstanding genetic
characteristics on plant establishment, pest and disease resistance. Super XL and XL the
least weight was consistently obtained from 377852 .1 and G.T.

For medium size tubers, the significantly heaviest tubers of 5.03 kg/10m2 still
came from the best entry 387039.15, out growing the weight of the prolific medium-
sized, tubers of entry 285378.27 having only 3.92 kg/10m2. The lowest was obtained
from 377852.1 having 0.47 kg/10m2. The differences in terms of number and weight was
seen to be the effect of the different entries yielding characteristics.

Number of Non-marketable Tubers

Entry 285378.27, that gave medium sized tubers similarly showed the highest
number of non-marketable small tubers. The number was, however, comparable to the
number obtained from the highest yielder 387039.15. Entry G.T was observed to have the
least number of marketable tubers with a mean of 25. It was observed that entries which
had the most number of non-marketable tubers were the most affected by the typhoon.

Weight of Non-Marketable Tubers

As indicated in Table 6, weight of non-marketable tubers from entry 387039.15
still significantly out weighed, the weight of the highest number of tubers from entry
377851.1. The differences could be due to genetic characteristics.

The non-marketable tubers considered in these study include very small, greened
and cracked tubers (Fig. 4).




Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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32










MARKETABLE











A.









NON-MARKETABLE














B.



Figure 4. Tubers of (A) marketable and (B) non-marketable

Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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33










GANZA












A.















387039.15







B.


Figure 5. Tubers per plot (A) Ganza and (B) 387039.15


Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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34
Table 6. Number and weight of non-marketable tubers of thirteen potato entries evaluated

ENTRY NUMBER
WEIGHT
(kg/10m2)
380579.3 103b 0.68abc
377852.1 67bc 0.27cd
720071 57bc 0.33cd
387039.15 152a 0.95a
28537827 161a 0.83ab
15.97.8 75bc 0.33cd
381530.1 67bc 0.33cd
G.T 25d 0.13d
Alpha 65bc 0.40bcd
Dejima 64c 0.43bcd
Ganza 83b 0.60abcd
Granola** 85b 0.68abc
Igorota** 57c 0.367bcd
CV (%)
15.62
14.69
Means with the same letter are not significantly different by DMRT (P>0.05).

Computed Yield Per Hectare


Table 7 shows the computed yield per hectare of the thirteen potato entries.
Interestingly, the significantly high computed yield of 387039.15 was 28.32 t/ha, Ganza
variety followed with 19.87 t/ha. Both results are within the previous reported 18-30 t/ha
yield of Igorota and Granola. The low results obtained from the other entries were due to
bad weather condition during the conduct of the study and varietal poor resistance to such
conditions.

For better selection, all the entries should also be planted during the dry season to
determine the specific performance and pinpoint which entry and variety is best,
especially for the farmers in Calasipan, Atok.





Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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35
Table 7. Computed yield per hectare of thirteen potato entries evaluated

ENTRY
YIELD PER HECTARE
(tons/ha)
380579.3 7.93c
377852.1 2.65c
720071 5.73c
387039.15 28.32a
28537827 9.58c
15.97.8 6.08c
381530.1 4.11c
G.T 2.93c
Alpha 4.04c
Dejima 3.70c
Ganza 19.87b
Granola** 5.26c
Igorota** 6.85c
CV (%)
24.85
Means with the same letter are not significantly different by DMRT (P>0.05).


Tubers Characteristics
Tuber
shape. Variability in the tuber shape of the thirteen potato entries is shown
in Table 8. Entries of Alpha, 720071, G.T, 28537827, Ganza, Granola and Igorota have
round tuber shape while 380579.3, 37785.1, 387039.15, and 381530.1 have elongated
tuber shape. It has been reported that round tubers are preferred for chips and elongated
or elliptic ones for fries. However, depending on the slicing machines any large tubers
shape could be used.
Skin
texture. Table 8 shows that the skin texture of entries. Alpha, 380579.3,
387039.15, G.T, 15.97.8 and Igorota have moderately smooth skin texture, 377852.1,
3815301, Ganza and Granola are smooth in skin texture; 720071 and Dejima have very
smooth skin texture; and 285378.27 with rough skin texture. Ideally, smooth to very
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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36
smooth skin are preferred both for table and processing purposes. For more fiber, the skin
could be left unpeeled.

Depth of eyes. It was observed that four of the thirteen potato entries used in the
study have shallow eyes, a criteria preferred by the processors. These are 377852.1,
720071, 285378.27 and Ganza. Shallow eyes gave less trimming loss, shorter time in
trimming, and higher volume of materials for chips, thus higher income.
The high yielding 387039.15, together with Dejima and Igorota have moderate by
deep eyes. The rest have deep eyes.

Table 8. Tuber characteristics of thirteen potato entries evaluated

ENTRY TUBERS
TUBER SKIN
DEPTH
SKIN
TUBER
SHAPE
SIZE
TEXTURE OF EYES COLOR
FLESH
COLOR
380579.3 Elliptic
Big Moderately
Deep Yellow
Yellow
smooth
377852.1 Elliptic
Medium
Smooth
Shallow
Yellow
White
720071 Round
Medium
Very
Shallow Yellow Yellow
smooth
387039.15 Elliptic
Large
Moderately
Moderate Yellow Cream
smooth
28537827 Round
Big Rough Shallow
Violet
Cream
15.97.8 Elliptic
Big
Moderately
Deep Yellow
White
smooth
381530.1 Elongate
Big Smooth
Deep Yellow
White
G.T Round
Medium
Moderately
Deep Yellow
Cream
smooth
Alpha Round
Medium
Moderately
Deep Yellow
Yellow
smooth
Dejima Elliptic
Medium
Very
Moderate Yellow White
smooth
Ganza Round
Large
Smooth
Shallow
Yellow
Yellow
Granola** Round
Large
Smooth
Deep Dark Cream
yellow
Igorota** Round
Large
Moderately
Moderate Yellow Cream
smooth








Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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37
Skin
color. Table 8 summarizes the tuber skin color of the thirteen potato entries.
As indicated, all the entries have yellow tuber skin color, except for 285378.27 which has
violet color. Traditionally, the yellow skin colors are referred both for table and
processing. The acceptance of violet skin color may differ on the consumer’s acceptance.
Flesh
color. Table 8 also shows also the variability in tuber flesh color of the
thirteen potato entries. Ganza, 720071, Alpha an 380579.3 have yellow tuber flesh color,
377852.1, 15.97.8, 381530.1 and Dejima with white flesh color; Granola, Igorota,
285378.27, G.T and 387039.15 with cream tuber flesh color. Both yellow and creaming
white are accepted for table in processing purposes. For more beta-carotene, colored ones
are preferred (Rastovski, 2003).

Storage Characters


Degree of Greening

For food consumption, greening is not accepted due to its glycoalkaloid substance
called solanine. To some local consumers in Manila and other areas, greening indicates
freshness as in vegetable but should be corrected for food safety.
To select resistant varieties from greening, the 13 entries were stored for two
months under diffused light condition. The degree of greening among the tubers of the
different entries varied as to the length of storage period.
At 15 days holding, no such greening occurred. However, the greening progress
as slightly severely as the storage was prolonged. Among the susceptible entries were the
Alpha and Igorota varieties gave the fastest greening development days in diffuse light
storage. Those of slight greening at 30 to 45 days were entries of 380579.31, 377852.1
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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38
720071, 387039.15, Ganza and Granola. The rest gave sever greening which could be use
for planting materials.
Entries with slow greening incidence are of advantage as potatoes are handled
from the farmers field to several traders hands without any protection coverings.
Moreover, potatoes are retailed in open markets and takes time to be distributed or
disposed of. During the sixty days of display all the entries had a rating of 6-10% greened
surface area. The tubers of entry 285378.27 had violet skinned which might have masked
the greening of tubers. This proves the study of Vandre (2003) that greening in red, violet
skin varieties were not easily detected. However, slicing the skin portion could be done to
check occurrence of greening with in the flesh portion.

Smith (1977) and Sinden (1992) explained that greening is caused by exposure to
ligh during harvesting, handling and marketing. The green color develops in the periderm
and in the outer parenchyma cells of the cortex at the same time form a toxic bitter-
tasting substance. The green taste is attributed to the formulation of glycoalkaloids.
Potato alkaloids comprise mainly two substances; a solanine (solanidine-glucose-
rhamnose). The consumption of glycoalkaloid contents my cause serious illness,
sometimes leading to death (Jahhax and Salunk, 1975 cited by Sinden, 1992), whether in
human or animals. The disease symptoms are those of acute food poisoning and found
that a solanine has inhibitions effect or cholisnesterose as demonstrated in studies on rat
heart cells.



Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
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Table 9. Degree of greening of thirteen potato entries evaluated

ENTRY
15 DAYS
30 DAYS
45 DAYS
60 DAYS
380579.3 1 2 2 3
377852.1 1 2 2 3
720071 1 2 2 3
387039.15
1 2 2 3
28537827 1 1 1 1
15.97.8 1 2 3 3
381530.1 1 2 3 3
G.T
1 2 3 3
Alpha 1 3 3 3
Dejima 1 2 3 3
Ganza 1 2 2 3
Granola**
1 2 2 3
Igorota** 1 3 3 3
Rating Scale: 1 – no greening; 2 – 1-5% greened surface area; 3 – 6-10% greened surface
area; 4 – 11% and above greened surface area


Greening formulation is affected by several factors such as entries as shown in
the study location, growing conditions, wounding, storage and exposure to light.
Gylcoalkaloid content depends on the potato entries and may average to two to ten
mg/100g fresh weight for the entire tuber. It is highest in the outermost cells layers hence
about 60% is eliminated on peeling. Considering this, potato-breeding programs should
include greening as one aspect for evaluation. The effects of growing conditions is
primarily observed in potatoes grown during short and cool seasons that promotes
production of immature tubers with high glycoalkaloid levels.

(Sinden 1992) further reported that damages and bruises increases the
glycoalkaloid content but dependent on the temperature; being slight at low temperature.
Storage at low temperature (4 to 8oC), high relative humidity and sprouting doubles the
glycoalkaloid content as compared to dry and warm condition (12 to 15oC).


Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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40
Degree of Decay

Based on the results, all the thirteen potato entries used have no incidence of
decay even after four days and half month of display probably due to the low
temperature.

Percentage Weight Loss


Table 10 and Fig. 6 indicates that the percentage of weight loss depends on the
thirteen entries evaluated and length of storage period. Higher percentage with loss were
incurred as storage period was prolonged. Igorota had significantly high percentage
weight loss at 10.1% but did not significantly differ with entries 380579.3, 377852.1, and
285378.27. Percentage weight loss were 10.0 kg, 9.7 kg, 9.8 kg and 9.8 kg, respectively.
The entries with minimal weight loss were observed from 387039.15 and Alpha. These
weight differences among entries were attributed to the genetic characteristics where
some entries possess thick skin and cuticles.

Table 10. Percent weight loss of thirteen potato entries evaluated

ENTRY
WEIGHT LOSS (%)
380579.3 10.0a
377852.1 9.7a
720071 9.8a
387039.15 7.7d
28537827 9.8a
15.97.8 8.7bc
381530.1 8.9bc
G.T 8.4cd
Alpha 7.9d
Dejima 9.3ab
Ganza 9.4ab
Granola** 8.7bc
Igorota** 10.1a
CV (%)
4.68
Means with the same letter are not significantly different by DMRT (P>0.05).
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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41
Other factors that contributed to high percentage weight loss during storage are
due to bio chemical change (Rastovski, 1981).

Number of Sprouts

The number of sprouts observed during storage depended on the evaluated entries.
Majority of entries produced three sprouts except entry 720071 that produced two
sprouts. The dormancy of potato tubers ranged from four to six months for seed purposes,
two to three sprouts is ideal for production.

However, for food and processing, sprouting must be prevented as sprouts utilizes
the food reserves or nutrients found within the tubers.

Dry Matter Content

The dry matter content is the simplest method of identifying varieties or entries
for processing in table purposes. High dry matter content at 21% and the above are ideal
for chips and fries. Values below this are good for table uses.
Table 11, the dry matter content significantly differed among the thirteen potato
entries. Highly significant differences were observed. Entry 720071 had the highest dry
matter content. This was followed by entry 380579.3 with 24%; 3778852.1, 285378.97,
381530.1, Dejima and Ganza with 22%, Alpha, check variety and Igorota with 21%.
Those of 20% DMC were from 15.97.8 and G.T. entries. The lowest were obtained from
entries 387039.15 with DMC of 17% and Granola with 18%.



Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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Table 11. Dry matter content of thirteen potato entries evaluated

ENTRY
DRY MATTER CONTENT (%)
380579.3 17f
377852.1 22c
720071 26a
387039.15 24b
28537827 22c
15.97.8 20d
381530.1 22c
G.T 20d
Alpha 21cd
Dejima 22c
Ganza 22c
Granola** 18e
Igorota** 21cd
CV (%)
2.70
Means with the same letter are not significantly different by DMRT (P>0.05).


The percent dry matter content indicates the solid matter that comprises the tuber
which is very important composition of potatoes. It is mainly determined genetically and
is dependent on the variety. The findings of NPRCRTC (1985) should that the dry matter
content of Igorota and other varieties are variable depending on the planting season,
fertilization and maturity among other factors. In this study the differences depend on the,
entries characteristics and performance during the unfavorable wet planting season.

Sensory Acceptability of Boiled Potato Tubers
Appearance. The Japanese Dejima varity which was claimed to be good for baked
potatoes gave liked moderately rating in visual apperance. Ganza, Igorota, 15.97,
285378.27, 377852.1 and 380579.3 gave liked slightly while the rest gave neither like nor
dislike ratings.


Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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Table 12. Sensory acceptability of boiled potatoes from thirteen entries.

ENTRY APPEARANCE COLOR
FLAVOR TEXTURE GENERAL
ACCEPTABILITY
380579.3 Like
slightly Neither Neither
Like nor
Like slightly
Like
Like nor
dislike
slightly
dislike
377852.1
Like slightly
Like nor
Like
Like nor
Like slightly
dislike
slightly
dislike
720071
Neither like nor Like nor
Like nor
Like nor
Like nor dislike
dislike
dislike
dislike
dislike
387039.15
Neither like nor Like
Like
Like
Like slightly
dislike
slightly
slightly
slightly
28537827 Like
slightly Like Like
Like
Like moderately
slightly
moderately moderately
15.97.8 Like
slightly
Like Like
Like
Like slightly
moderately slightly
slightly
381530.1
Neither like nor Like
Like
Like nor dislike
dislike
slightly
slightly
G.T
Neither like nor Like
Like
Like
Like slightly
dislike
slightly
moderately slightly
Alpha Like
slightly
Like Like
Like
Like slightly
slightly
slightly
slightly
Dejima Like
Like
Like
Like
Like moderately
moderately
slightly
slightly
slightly
Ganza Like
slightly
Like Like
Like
Like moderately
moderately slightly
slightly
Granola
Neither like nor Like
Like
Like nor
Like slightly
dislike
slightly
moderately dislike
Igorota Like
slightly
Like Like
Like
Like moderately
slightly
slightly
slightly

Color. In terms of color varity Ganza and entry 15.97.8 gave liked moderately
rating. entries 380579.3, Alpha, 387039.15, G.T, 285378.27, 381539.1, Dejima, Granola
and Igorota were like slightly. Entries of 720071 and 377852.1 were rated like nor dislike
while entries of 15.97.8 and Ganza were rated liked slightly while entries of 720071 and
377852.1 were rated like nor dislike rating.
Flavor. For flavor acceptability entries 380579.3 and 720071 were evaluated like
nor dislike while entries G.T, 285378 and Granola gave like moderately rating. The rest
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
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44
were rated like slightly. Flavor, in this study, describes how they accept and perceive the
strong potato flavor.
Texture. In terms of texture, the significant varieties come from Granola, 720071,
377852.1 and 380579.3 with rating of neither like nor dislike. Entries Alpha, high
yielding 387039.15, G.T, 15.97.8, 381530.1, Dejima, Ganza and Igorota gave rating liked
slightly while 285378.27 was solely liked moderately (Table12).
General Acceptability. For the general acceptability, of the boiled potatoes only
for entries or rated like moderately, namely; entry 285378.27, Dejima, Ganza, and
Igorota. With slightly liked rating were entries 380579.3, 377852.1, 387039.15, 15.97.8,
G.T. Al.pha, and Granola. The rest gave neither like nor dislike rating.

Chipping Quality
Percentage
chips
recovery. The percent chip recovery varied among the thirteen
potato entries shows in (Table 13). The highest 36 percent was obtained from chips of the
high yielding 387039.15. varieties Igorota, Ganza, Alpha and intries G.T. 15.97.8 amd
720071, gave 34% while the rest had 31% chip recovery.

Generally, thus of high dry matter content gave the highest chip recovery
percentage recovery.

Degree of browning. The potato chips evaluated either had slight, moderate and
no browning at all absences of browning was observed in Granola chips. Those of slight
browning were entries 380579.3, 720071, 15.97.8, 381530.1, G.T., Alpha, and Igorota
the rest have moderate browning.
Browning rating is essential to determine the ideal color for potato chips. The
result could be due to the high percentage of dry matter and low and sugar content.
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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Table 13. Chipping quality of thirteen fried potato entries evaluated

ENTRY %
CHIP
DEGREE OF CRISPINESS OILINESS FLAVOR
GENERAL
RECOVERY BROWING
ACCEPTA-
ACCEPTA
BILITY
-BILITY
380579.3 31
Slight Slightly
Moderately Strong potato Like very
browning
crispy
oily
flavor
much
377852.1 31
Moderate
Slightly
Slightly
Strong potato Like
browning
crispy
oily
flavor
extremely
720071 34
Slight Slightly
Slightly
Strong potato Like
browning
crispy
oily
flavor
slightly
387039.15 36 Moderate
Slightly
Slightly
Strong potato Like
browning
crispy
oily
flavor
slightly
28537827 31 Moderate
Slightly
Slightly
Strong potato Like
browning
crispy
oily
flavor
slightly
15.97.8 34
Slight Slightly
Moderately Strong potato Like
browning
crispy
oily
flavor
extremely
381530.1 31
Slight Slightly
Slightly
Strong potato Like
browning
crispy
oily
flavor
extremely
G.T 34
Slight
Slightly
Slightly
Strong potato Like much
browning
crispy
oily
flavor
Alpha 34
Slight
Slightly
Slightly
Strong potato Like very
browning
crispy
oily
flavor
much
Dejima 31
Slight
Slightly
Slightly
Strong potato Like very
browning
crispy
oily
flavor
much
Ganza 34
Moderate
Slightly
Slightly
Strong potato Like much
browning
crispy
oily
flavor
Granola 31
No
browning
Slightly
Slightly
Strong potato Like much
crispy
oily
flavor
Igorota 34
Slight
Slightly
Slightly
Very strong
Like
browning
crispy
oily
potato flavor
extremely









Crispiness. Chips from all the thirteen potato entries were evaluated slightly
crispy. It is not clear why all the panelists gave the same rating but could be that the
samples taste similarly or they were not properly trained nor they felt satiated with may
samples to evaluate.
Oiliness. Slight to moderately oily was obtained from the potato chips evaluated.
Those of moderately oily chips were found 380579.3 with 17% DMC and from 15.97.8
with 20% DMC. Literature reviews reported that the dry matter content is correlated with
the oiliness of chips. The higher dry matter content, the less oil uptake. Thus, entries
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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46
having 21% and more most of the chips with the 21% dry matter obtained from the potato
entries gave the rating was slightly oily.
Flavor. Flavor acceptability of the thirteen potato entries is shown in Table 13. All
of the chips from the 12 entries gave strong potato flavor, except for Igorota that had a
rating of very strong potato flavor. Flavor could be improved by adding seasonings such
as salt, pepper, garlic powder, cheese powder and other desired flavoring.
General
acceptability. Table 13 presents the general acceptability of the chips for
the 13 entries. Results show that chips from Igorota, 381530.1, 15.97.8 and 377852.1
were rated like extremely those chips of like very much were 380579.3, Alpha and
Dejima. Granola, Ganza, and G.T gave only liked very much, rating while the rest gave
like slightly acceptability. Sensory rating acceptability using appropriate frying machines
could better improved the quality of the chips.






















Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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SUMMARY, CONCLUSION AND RECOMMENDATION


Summary

The tuberlets of the thirteen potato entries that originated from CIP-Peru, USA,
Japan and NPRCRTC were grown during wet season in Calasipan, Atok, Benguet, from
May 2005 to September 2006 and stored under Atok condition. This was done to
determine and evaluate the growth and agronomic characteristics of potato entries that
will be adopted to Calasipan, Atok, Benguet condition.

Results revealed significant differences, in terms of percent survival, plant vigor,
reaction to pest and disease, growth performance, agronomic characteristics, postharvest
quality, eating and chipping qualities.

In terms of plant growth, nine among 13 potato entries gave highly vigorous, high
survival rate of 95 to 98%, and highly resistance to pests rating while four of them had
moderately vigorous rating at 30 and 60 days from planting and these are 3778521, G. T.,
Alpha and Dejima. These entries similarly gave poorer survival rate of 83 to 85%, and a
just resistant rating to pest infestation against those highly resistant rating of other entries.

Based on marketable yield parameters, entry 387039.1 exhibited better yield
despite typhoon disturbances. The entry produced the highest number and weight of
super extra large, extra big, and medium sized tubers, and including the non-marketable
tubers that are of small sizes, greened and cracked tubers. The new check variety, Ganza
followed similar trend but of significantly lower values. The other processing variety,
Igorota gave comparable lower marketable yield values with other entries. The lowest
yielders or typhoon-sensitive ones were 377852.1, G. T., Alpha, Dejima, and Granola.
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
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Entry 28537827 is highlighted as excellent producer of medium sized and non-
marketable tubers.

As to computed yield per hectare, entry 387039.1 gave 28.32 tons/ha, followed by
Ganza with 19.87 tons/ha and the lowest came from 377852.1.

The french fry preferred elongated shape are from the high yielding and large type
387039.15, 380579.3, 377852.1, 15.97.8, 381530.1, and Dejima. The rest are of round to
round oval shape that are also good for chips. The drawback, however, of the high
yielding and large tuber size 387039.15 was its moderate smooth skin and moderately
deep eye that may affect trimming efficiency. Other entries with smooth skin and shallow
eyes are 377852.1, 720071, 381530.1, Dejima, Ganza and Granola. The other shallow
eyes potato is 28537827. Majority of the entries evaluated are of yellow tuber skin except
28537827 that has violet color. The tuber flesh of the potatoes were of yellow, white and
cream.

Greening, during storage was observed at 30 days. Higher degree at 6-9% was
observed in a variety Alpha and Igorota while the rest gave 1-5% slight greening.
Majority gave progressive greening degree when kept at 60 days. The violet skin color of
28537827 masked the greening incidence but should have been sliced to detect incidence
in the flesh.

Percentage weight loss at 60 days ranged from 7.7% to 10.1%. The lowest was
obtained from the high yielding and large-sized entry 387039.15.

For the dry matter content, majority gave high values. Based on the recommended
21% and above the processing, these were obtained from 377852.1, 720071, high
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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49
yielding 387039.15, 28537827, 381530.1, Alpha, Dejima, Ganza, and Igorota,. The
highest was 26% from 720071. The rest gave 20% and below of 17%.

When boiled, it was observed that 28537827, Ganza and Dejima gave like slightly
to like moderately acceptability rating on the appearance, color, flavor, texture and
general acceptability. The rest gave acceptability specific to one or two sensory attributes.

For chips, majority gave slightly crispy rating. Moderately oily rating was
obtained from entries with lower dry matter content such as 38079.3 and 15.97.8. The
rest have slightly oily. Perceptible potato flavor were noted in all the entries. The general
acceptability ranged from like slightly to like extremely. The latter were obtained from
chips of 377852.1, 381530.1, 15.97.8 and Igorota.

With the exception of 387039.15 and Ganza that exhibited good plant growth,
high yield, high dry matter content, good eating and processing qualities, other entries
should further be evaluated for dry season production and locating trials to determine
adaptability. Otherwise, they should be used for biotechnology studies to clone or breed
their specific traits and combine to other desired traits to suit industry needs.

Conclusion
Based on the results of the study, it is concluded that entries 387039.15, Ganza,
Igorota, 285378.27, 15.97.8, 380579.3, Alpha and Granola have potentials for table
potato production and processing. In terms of growth and agronomic characters these
entries produced the highest marketable yield and seed tuber size. For table purposes, all
the entries are recommended based on their acceptability. For seed tubers, these thirteen
entries were considered as they were resistant to leafminer and late blight except for
285378.27 due its violet color which is not accepted common to consumers.
Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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50
The postharvest characteristics of the different entries stored under diffuse light
storeroom may be attributed to their varietal characteristics, for instance skin color made
it difficult to detect greening. Potato tubers from entries Alpha, Granola, 285378.27,
377852.1 and 15.97.8 had the lowest percentage weight loss which had a good
postharvest characteristics. Decay did not appear on the thirteen potato entries,
387039.15, Alpha, 380579.3, Igorota and Ganza produced sprouts on the fourth months
of storage.

Recommendation
Entries 387039.15, 15.97.8, Alpha, 381530.1, 380579.3, Ganza, Igorota and
Granola have potentials for postharvest qualities. Hence, it is suggested that these entries
could be further evaluated for their growth and yield performance in other potato
production areas. If their agronomic performance is stable these entries can be
recommended for table potato, seed tuber and for processing production.
Entries Ganza and 387039.15 are highly recommended for rainy season planting
in Calasipan, Atok, Benguet as indicated by their good yield and adaptability despite of
the bad weather during the experimentation period.








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SUNIL, K. R. 1990. Varietal evaluation of promising lines and path coefficient analysis
of pole snap beans. MS Thesis BSU, La Trinidad, Benguet.

TOOSEY, R. D. 1958. Effect of number of sprout per set on yield Grading of Main Crop
Potatoes Nature. Pp. 182-270.

USDA. 1992. Specialty potatoes increase production. http://www/stc.ucdavis.edu/
pubs/brochures/ specialty potatoes. html.

VANDRE, W. 2003. Green potatoes the problem and the solution.
http:1166.218.17225/search/cache/p=rule+ of + solanine.

YAMAMOTO, N. 1987. Potato Processing: Learning From a Traditional Andean
System. In: report of the Third Social Science Planning Conferences. CIP. Lima
Peru.

ZAMORA, A. B. 1994. Micro propagation and elimination procedure for conservation,
dissemination and production in humid tropics. Netherlands: Centre for
Agricultural Publishing and Documentation. P. 69.









Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

---

APPENDICES


Appendix Table 1. Plant vigor at 30 DAP of thirteen potato entries

ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 5
5
5
15
5a
V2 3
3
2
8
3b
V3 3
2
3
8
3b
V4 5
5
5
15
5a
V5 5
5
5
15
5a
V6 5
5
5
15
5a
V7 5
5
5
15
5a
V8 3
3
2
8
3b
V9 3
2
2
7
2b
V10 3
5
2
10
3b
V11 5
5
5
15
5a
V12 5
5
5
15
5a
V13 5
5
5
15
5a
TOTAL 55
55
51
51
4.12

ANALYSIS OF VARIANCE
SOURCE OF DEGREE OF
SUM OF
MEAN OF COMPUTED
TABULAR F
VARIATION
FREEDOM
SQUARES SQUARES
Fc
0.05 0.01
Replication 2 1.385
0.692

Entry
12
46.410
3.868
8.23**
1.82
2.35
Error 24
11.282
0.470



TOTAL 38

** - highly significant



Coefficient of Variation = 16.51 %


Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

---

55
Appendix Table 2. Plant vigor at 60 DAP of thirteen potato entries
ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 5
5
2
12
4ab
V2 2
3
3
8
3b
V3 2
2
2
6
2b
V4 5
5
5
15
5a
V5 5
5
5
15
5a
V6 4
4
3
11
4ab
V7 3
5
4
12
4ab
V8 2
2
3
7
2b
V9 3
2
2
7
2b
V10 2
2
2
6
2b
V11 5
5
5
15
5a
V12 4
5
5
14
4ab
V13 5
4
4
13
4ab
TOTAL 47
49
45
141
3.61


ANALYSIS OF VARIANCE
SOURCE OF DEGREE OF
SUM OF
MEAN OF COMPUTED
TABULAR F
VARIATION
FREEDOM
SQUARES SQUARES
Fc
0.05 0.01
Replication 2 0.359
0.179

Entry 12
27.026
2.252
2.58**
1.82
2.35
Error 24
20.974
0.0874



TOTAL 38
48.359


** - highly significant



Coefficient of Variation = 24.63 %



Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

---

56
Appendix Table 3. Plant survival (%) of thirteen potato entries
ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 95
97
97
289
96ab
V2 93
95
95
283
94b
V3 83
85
83
251
84c
V4 98
97
98
293
98a
V5 97
95
97
289
96ab
V6 93
97
97
287
96ab
V7 83
83
85
251
84a
V8 98
97
98
293
98c
V9 90
83
85
258
86c
V10 83
85
83
251
84c
V11 97
98
98
293
98c
V12 93
95
95
283
94b
V13 97
98
97
292
97a
TOTAL 1200
1205
1208
3613
92.64


ANALYSIS OF VARIANCE
SOURCE OF DEGREE OF
SUM OF
MEAN OF COMPUTED
TABULAR F
VARIATION
FREEDOM
SQUARES SQUARES
Fc
0.05 0.01
Replication 2 2.513
1.256

Entry 12
1276.974
106.415
46.03**
1.82
2.35
Error 24
55.487
2.312



TOTAL 38
1334.974


** - highly significant



Coefficient of Variation = 1.64 %



Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

---

57
Appendix Table 4. Pest and disease incidence (leafminer) at 45 DAP of thirteen potato
entries

ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 1
1
1
3
1b
V2 1
2
1
4
1b
V3 1
1
2
4
1b
V4 1
1
1
3
1b
V5 1
1
1
3
1b
V6 1
1
1
3
1b
V7 1
1
1
3
1b
V8 2
2
2
6
2a
V9 2
1
2
5
2a
V10 2
2
2
6
2a
V11 1
1
1
3
1b
V12 1
1
1
3
1b
V13 1
1
1
3
1b
TOTAL 16
16
17
49
1.26


ANALYSIS OF VARIANCE
SOURCE OF DEGREE OF
SUM OF
MEAN OF COMPUTED
TABULAR F
VARIATION
FREEDOM
SQUARES SQUARES
Fc
0.05 0.01
Replication 2 0.051
0.026

Entry 12
5.436
0.453
5.58**
1.82
2.35
Error 24
1.949
0.081



TOTAL 38
7.436


** - highly significant



Coefficient of Variation = 22.68 %


Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

---

58
Appendix Table 5. Late blight 45 DAP of thirteen potato entries
ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 1
1
1
3
1b
V2 2
1
2
5
2a
V3 2
2
2
6
2a
V4 1
1
1
3
1b
V5 1
1
1
3
1b
V6 1
1
1
3
1b
V7 2
2
2
6
2b
V8 1
1
1
3
1a
V9 2
2
2
6
2a
V10 2
2
2
6
2a
V11 1
1
1
3
1b
V12 1
1
1
3
1b
V13 1
1
1
3
1b
TOTAL 18
17
18
53
1.36


ANALYSIS OF VARIANCE
SOURCE OF DEGREE OF
SUM OF
MEAN OF COMPUTED
TABULAR F
VARIATION
FREEDOM
SQUARES SQUARES
Fc
0.05 0.01
Replication 2 0.043
0.022

Entry 12
8.464
0.705
26.03**
1.82
2.35
Error 24
0.650
0.027



TOTAL 38
9.157


** - highly significant



Coefficient of Variation = 12.16 %



Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

---

59
Appendix Table 6. Number of SXL tubers of thirteen potato entries
ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 10
15
33
58
19b
V2 2
13
6
21
7b
V3 8
9
7
24
8b
V4 100
55
74
229
76a
V5 24
7
24
55
18b
V6 19
10
21
50
17b
V7 11
9
4
24
8b
V8 10
24
14
48
16b
V9 10
7
11
28
9b
V10 13
10
3
26
9b
V11 44
56
91
191
64a
V12 18
14
10
42
14b
V13 29
11
18
58
19b
TOTAL 298
240
316
854
21.90


ANALYSIS OF VARIANCE
SOURCE OF DEGREE OF
SUM OF
MEAN OF COMPUTED
TABULAR F
VARIATION
FREEDOM
SQUARES SQUARES
Fc
0.05 0.01
Replication 2 242.667
121.333

Entry 12
17398.256
1449.855
11.69**
1.82
2.35
Error 24
2976.667
124.028



TOTAL 38
20617.590


** - highly significant



Coefficient of Variation = 26.96 %



Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

---

60
Appendix Table 7. Number of extra big tubers of thirteen potato entries
ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 20
40
31
91
30b
V2 5
15
15
35
12b
V3 20
15
10
45
15b
V4 110
69
97
276
92a
V5 40
20
60
120
40b
V6 25
20
41
86
29b
V7 16
20
10
46
15b
V8 24
20
26
70
23b
V9 14
22
12
48
16b
V10 18
13
19
50
17b
V11 39
40
140
219
73a
V12 24
20
20
64
21b
V13 54
23
20
97
32b
TOTAL 409
337
501
1247
31.97


ANALYSIS OF VARIANCE
SOURCE OF DEGREE OF
SUM OF
MEAN OF COMPUTED
TABULAR F
VARIATION
FREEDOM
SQUARES SQUARES
Fc
0.05 0.01
Replication 2
1039.590
519

Entry 12
21057.641
1754.803
4.79**
1.82
2.35
Error 24
8795.744
366.489



TOTAL 38
30892.974


** - highly significant



Coefficient of Variation = 29.72 %



Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

---

61
Appendix Table 8. Number of big tubers (15-25 g) of thirteen potato entries
ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 78
119
140
337
112c
V2 28
72
34
134
45d
V3 56
56
78
190
63cd
V4 176
164
232
572
191b
V5 241
224
268
733
244a
V6 70
180
80
330
110c
V7 65
68
86
219
73cd
V8 38
30
23
91
30d
V9 42
58
60
160
53d
V10 58
74
56
188
63cd
V11 90
119
111
320
107c
V12 85
108
10
203
68cd
V13 76
76
73
225
75cd
TOTAL 1103
1348
1251
3702
94.9


ANALYSIS OF VARIANCE
SOURCE OF
DEGREES
SUM OF
MEAN OF COMPUTED TABULAR F
VARIATION
OF
SQUARES SQUARES
Fc
0.05 0.01
FREEDOM
Replication 2 2342.000
1171.000

Entry 12
132734.103
11061.175
14.28**
1.82
2.35
Error 24
18594.667
779.778



TOTAL 38
1.53670.769



** - highly significant



Coefficient of Variation = 29.32 %



Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

---

62
Appendix Table 9. Number of non-marketable tubers of thirteen potato entries
ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 120
64
126
310
103b
V2 58
61
66
185
67bc
V3 40
96
34
170
57bc
V4 106
148
203
427
152a
V5 156
130
197
483
161a
V6 56
68
100
224
75bc
V7 32
68
102
202
67bc
V8 31
21
23
75
25d
V9 37
60
98
195
65bc
V10 33
84
75
192
64bc
V11 50
64
136
250
83b
V12 63
88
105
256
85b
V13 68
46
57
171
57bc
TOTAL 850
998
1322
3170
81.28

ANALYSIS OF VARIANCE
SOURCE OF
DEGREES
SUM OF
MEAN OF COMPUTED TABULAR F
VARIATION
OF
SQUARES SQUARES
Fc
0.05 0.01
FREEDOM
Replication 2 8965.744
4482.872

Entry 12
52380.564
4365.047
6.95**
1.82
2.35
Error 24
15073.590
628.066



TOTAL 38
76419.892



** - highly significant



Coefficient of Variation = 15.62 %




Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

---

63
Appendix Table 10. Weight of SXL tubers of thirteen potato entries
ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 0.80
1.10
2.75
4.65
1.55b
V2 0.25
0.90
0.60
1.75
0.58b
V3 0.65
6.20
0.60
7.45
2.48b
V4 11.1
0.90
9.00
21.00
7.00a
V5 1.30
0.80
1.25
3.35
1.12b
V6 1.30
1.00
1.60
3.90
1.30b
V7 0.50
1.35
1.20
3.05
1.02b
V8 0.75
0.80
0.50
2.05
0.68b
V9 0.60
0.75
0.80
2.15
0.72b
V10 0.65
0.75
0.40
1.80
0.60b
V11 6.65
5.55
8.30
17.50
5.83b
V12 0.75
1.25
0.65
2.65
0.88b
V13 2.20
0.90
1.50
4.60
1.53b
TOTAL 24.50
22.25
29.15
75.90
1.95

ANALYSIS OF VARIANCE
SOURCE OF
DEGREES
SUM OF
MEAN OF COMPUTED TABULAR F
VARIATION
OF
SQUARES SQUARES
Fc
0.05 0.01
FREEDOM
Replication 2 1.905
0.953

Entry 12
153.427
12.786
3.33**
1.82
2.35
Error 24
92.120
3.838



TOTAL 38
247.452



** - highly significant



Coefficient of Variation = 21.83 %




Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

---

64
Appendix Table 11. Weight of extra big tubers of thirteen potato entries
ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 .85
2.9
1.25
5.00
1.67b
V2 .2
1.2
.6
2.00
0.67b
V3 .9
.65
.4
1.95
0.65b
V4 5.25
4.4
5.0
14.65
4.88a
V5 1.55
1.1
1.9
4.55
1.52b
V6 .8
1.1
1.55
3.45
1.15b
V7 .8
.6
1.0
2.40
0.80b
V8
.55 .8 .3 1.65 0.55b
V9 .45
1.0
.75
2.20
0.73b
V10 .6
.6
.75
1.95
0.65b
V11 .6
2.9
7.1
10.66
3.53a
V12 .65
1.0
.9
2.55
0.85b
V13 1.8
.6
1.0
3.40
1.13b
TOTAL 15
18.85
22.45
56.35
1.44

ANALYSIS OF VARIANCE
SOURCE OF
DEGREES
SUM OF
MEAN OF COMPUTED TABULAR F
VARIATION
OF
SQUARES SQUARES
Fc
0.05 0.01
FREEDOM
Replication 2 2.164
1.082

Entry 12
60.107
5.092
4.94**
1.82
2.35
Error 24
24.728
1.030



TOTAL 38


** - highly significant



Coefficient of Variation = 22.97 %




Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

---

65
Appendix Table 12. Weight of big tubers of thirteen potato entries
ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 .9
3.2
2.75
6.85
2.28cd
V2 .3
.5
.6
1.40
0.47e
V3 .9
1.0
.75
2.65
0.88e
V4 4.5
5.1
5.5
15.10
5.03a
V5 2.7
4.2
4.85
11.75
3.92b
V6 1.1
1.95
1.75
4.80
1.60cdc
V7 .9
1.1
1.2
3.20
1.07e
V8 .7
.85
.2
1.75
0.58e
V9 .65
1.5
1.75
3.90
1.30dc
V10 .8
1.4
.75
2.95
0.98e
V11 .6
3.2
3.75
7.55
2.52e
V12 1.1
2.3
.9
4.30
1.43dc
V13 1.3
1.8
1.6
4.70
1.57cdc
TOTAL 16.45
28.1
26.35
70.9 1.82

ANALYSIS OF VARIANCE
SOURCE OF
DEGREES
SUM OF
MEAN OF COMPUTED TABULAR F
VARIATION
OF
SQUARES SQUARES
Fc
0.05 0.01
FREEDOM
Replication 2 6.072
3.036

Entry 12
64.379
5.365
15.23**
1.82
2.35
Error 24
8.452
0.352



TOTAL 38
78.902



** - highly significant



Coefficient of Variation = 24.0%




Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

---

66
Appendix Table 13. Weight of non-marketable tubers of thirteen potato entries
ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 .55
.5
1.0
2.05
0.68abc
V2 .3
.2
.3
0.80
0.27cd
V3 .25
.45
.3
1.00
0.33cd
V4 .6
1.25
1.0
2.85
0.95a
V5 .9
.55
1.05
2.50
0.83ab
V6 .4
.5
.1
1.00
0.33cd
V7 .1
.3
.6
1.00
0.33cd
V8
.2 .1 .1 0.40 0.13d
V9 .35
.5
.35
1.20
0.40bcd
V10 .2
.2
.9
1.30
0.43bcd
V11 .3
.5
1.0
1.80
0.60abcd
V12 .25
1.1
.7
2.05
0.68abc
V13 .5
.3
.3
1.10
0.37bcd
TOTAL 4.9
6.45
7.7
19.05
0.49

ANALYSIS OF VARIANCE
SOURCE OF
DEGREES
SUM OF
MEAN OF COMPUTED TABULAR F
VARIATION
OF
SQUARES SQUARES
Fc
0.05 0.01
FREEDOM
Replication 2 0.303
0.151

Entry 12
2.081
0.173
2.90**
1.82
2.35
Error 24
1.434
0.060



TOTAL 38
3.817



** - highly significant



Coefficient of Variation = 14.69 %




Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

---

67
Appendix Table 14. Computed yield per hectare (tons/ha) of thirteen potato entries
ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 3.97
9.87
9.94
23.78
7.93e
V2 1.67
3.59
2.69
7.95
2.65c
V3 4.29
10.26
2.63
17.18
5.73c
V4 41.73
14.94
28.28
84.95
28.32a
V5 8.61
8.53
11.60
28.74
9.58e
V6 6.0
5.83
6.41
18.24
6.08c
V7 2.9
4.29
5.13
12.32
4.11c
V8 2.82
4.55
1.41
8.78
2.93c
V9 2.63
4.81
4.68
12.12
4.04c
V10 3.72
3.78
3.59
11.09
3.70c
V11 18.21
15.58
25.83
59.62
19.87b
V12 4.49
7.24
4.04
15.77
5.26c
V13 10.3
4.61
5.64
20.55
6.85c
TOTAL 111.34
97.88
111.87
321.09
8.23

ANALYSIS OF VARIANCE
SOURCE OF
DEGREES
SUM OF
MEAN OF COMPUTED TABULAR F
VARIATION
OF
SQUARES SQUARES
Fc
0.05 0.01
FREEDOM
Replication 2 9.671
4.836

Entry 12
2030.883
169.240
8.05**
1.82
2.35
Error 24
504.580
4.024



TOTAL 38
2545.134



** - highly significant



Coefficient of Variation = 24.85 %




Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

---

68
Appendix Table 15. Degree of greening 1st week of display of thirteen potato entries
ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 1
1
1
3
1.0
V2 1
1
1
3
1.0
V3 1
1
1
3
1.0
V4 2
1
1
4
1.3
V5 0
0
0
0
0
V6 1
1
2
4
1.3
V7 1
2
1
4
1.3
V8 1
1
1
3
1.0
V9 1
2
1
4
1.3
V10 1
1
2
4
1.3
V11 1
1
1
3
1.0
V12 1
1
1
3
1.0
V13 1
2

4
1.3
TOTAL 13
15
14
44
1.12


ANALYSIS OF VARIANCE
SOURCE OF DEGREES OF
SUM OF
MEAN OF COMPUTED TABULAR F
VARIATION
FREEDOM
SQUARES SQUARES
Fc
0.05 0.01
Treatment
12
1.077
0.090
0.58ns 2.15
2.96
Error 24
4.00
0.154



TOTAL 28
5.077



ns – not significant


Coefficient of Variation = 12.92 %







Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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69
Appendix Table 16. Degree of greening 2nd week of display of thirteen potato entries
ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 2
2
2
6
2.0
V2 2
2
1
5
2.0
V3 2
2
2
6
2.0
V4 2
1
2
5
2.0
V5 0
0
0
0
0
V6 2
2
3
7
2.0
V7 2
3
2
7
2.0
V8 2
3
2
7
2.0
V9 2
3
3
8
3.0
V10 3
2
2
7
2.0
V11 1
2
2
5
2.0
V12 2
2
1
5
2.0
V13 2
3
3
8
3.0
TOTAL 24
27
25
76 1.9


ANALYSIS OF VARIANCE
SOURCE OF DEGREES OF
SUM OF
MEAN OF COMPUTED TABULAR F
VARIATION
FREEDOM
SQUARES SQUARES
Fc
0.05 0.01
Entry 12
4.667
0.389
1.38ns 2.15
2.96
Error 24
7.333
0.282



TOTAL 28
12.000



ns – not significant


Coefficient of Variation =26.55 %





Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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70
Appendix Table 17. Degree of greening 3rd week of display of thirteen potato entries
ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 2
2
2
6
2
V2 2
2
2
6
2
V3 2
2
2
6
2
V4 2
3
3
8
3
V5 0
0
0
0
0
V6 2
3
3
8
3
V7 3
2
2
7
2
V8 2
3
3
8
3
V9 2
3
3
8
3
V10 3
2
2
7
2
V11 2
3
3
8
3
V12 2
3
3
8
3
V13 3
3
3
9
3
TOTAL 27
31
31
89
2.28


ANALYSIS OF VARIANCE
SOURCE OF DEGREES OF
SUM OF
MEAN OF COMPUTED TABULAR F
VARIATION
FREEDOM
SQUARES SQUARES
Fc
0.05 0.01
Entry 12
7.103
0.175
0.62ns 2.15
2.96
Error 24
7.333
0.282



TOTAL 28
9.436



ns – not significant


Coefficient of Variation =22.03 %





Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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71

Appendix Table 18. Degree of greening 4th week of display of thirteen potato entries
ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 2
3
3
8
3
V2 3
3
2
8
3
V3 3
3
3
9
3
V4 3
2
3
8
3
V5 0
0
0
0
0
V6 3
3
3
9
3
V7 3
3
3
9
3
V8 2
3
3
8
3
V9 3
3
3
9
3
V10 3
3
3
9
3
V11 2
3
2
7
2
V12 3
2
3
8
3
V13 3
3
4
10
3
TOTAL 33
34
35
102
2.61


ANALYSIS OF VARIANCE
SOURCE OF DEGREES OF
SUM OF
MEAN OF COMPUTED TABULAR F
VARIATION
FREEDOM
SQUARES SQUARES
Fc
0.05 0.01
Entry 12
1.590
0.132
0.65ns 2.15
2.96
Error 24
5.333
0.205



TOTAL 28
6.923



ns - not significant


Coefficient of Variation = 16.36%





Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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72
Appendix Table 19. Percentage weight loss at first week of display of thirteen potato
entries

ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 0.1
0.1
0
0.2
0.06
V2 0
0.1
0
0.1
0.03
V3 0
0
0.2
0.2
0.06
V4 0.2
0.1
0
0.3
0.10
V5 0
0
0.1
0.1
0.03
V6 0.2
0
0.1
0.3
0.10
V7 0
0.1
0
0.1
0.03
V8 0
0
0.2
0.2
0.06
V9 0
0.1
0.1
0.2
0.06
V10 0
0.1
0
0.1
0.03
V11 0
0.1
0
0.1
0.03
V12 0.1
0
0
0.1
0.03
V13 0.2
0.1
0.1
0.4
0.13
TOTAL 0.8
0.8
0.8
24
0.06


ANALYSIS OF VARIANCE
SOURCE OF DEGREES OF
SUM OF
MEAN OF COMPUTED TABULAR F
VARIATION
FREEDOM
SQUARES SQUARES
Fc
0.05 0.01
Entry 12
0.039
0.003
0.55ns 2.15
2.96
Error 24
0.153
0.056



TOTAL 28
1.868



ns - not significant


Coefficient of Variation = 7.26 %





Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

---

73
Appendix Table 20. Percentage weight loss during 2nd week of display of thirteen potato
entries

ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 0.1
0.2
0.3
0.6
0.20
V2 0.1
0.2
0
0.3
0.10
V3 0.2
0.1
0.5
0.8
0.26
V4 0.5
0.1
0
0.6
0.20
V5 0
0.2
0.4
0.6
0.20
V6 0.1
0
0.4
0.5
0.16
V7 0.3
0.3
0.1
0.7
0.23
V8 0.2
0
0.4
0.6
0.20
V9 0.2
0.4
0.2
0.8
0.26
V10 0.2
0.4
0.2
0.8
0.26
V11 0.2
0.1
0.2
0.5
0.16
V12 0.1
0
0.4
0.5
0.16
V13 0.6
0.2
0.2
1.0
0.33
TOTAL 2.8
2.2
3.3
8.3
0.21


ANALYSIS OF VARIANCE
SOURCE OF DEGREES OF
SUM OF
MEAN OF COMPUTED TABULAR F
VARIATION
FREEDOM
SQUARES SQUARES
Fc
0.05 0.01
Entry 12
0.130
0.011
0.36ns 2.15
2.96
Error 24
0.793
0.031



TOTAL 28
0.924



ns - not significant


Coefficient of Variation =12.14 %



Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

---

74
Appendix Table 21. Percentage weight loss after 3rd week of display of thirteen potato
entries

ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 5.2
4.7
4.2
14.1
4.7b
V2 1.9
1.6
1.6
5.1
1.7e
V3 3.8
1.6
2.0
7.4
2.5cdc
V4 3.1
2.2
2.7
8.0
2.7cdc
V5 2.0
2.3
3.5
7.8
2.6cdc
V6 2.2
2.0
2.5
6.7
2.2cdc
V7 3.7
2.5
3.2
9.4
3.1c
V8 2.7
2.6
3.2
8.5
2.8cd
V9 2.5
3.2
3.2
8.9
3.0c
V10 2.2
3.2
2.1
7.6
2.5cdc
V11 2.0
1.2
1.9
5.1
1.7e
V12 1.7
2.2
1.9
5.8
1.0dc
V13 8.8
7.9
8.3
25.0
8.3a
TOTAL 41.8
37.2
40.3
119.3
3.0


ANALYSIS OF VARIANCE
SOURCE OF DEGREES OF
SUM OF
MEAN OF COMPUTED TABULAR F
VARIATION
FREEDOM
SQUARES SQUARES
Fc
0.05 0.01
Entry 12
111.632
9.303
29.64**
2.15
2.96
Error 24
8.160
0.314



TOTAL 28
119.792



** - highly significant



Coefficient of Variation =18.30 %




Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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75
Appendix Table 22.Percentage weight loss after 4th week of display of thirteen potato
entries

ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 10.2
9.8
10
30.0
10.0a
V2 8.5
7.3
8
23.8
7.9d
V3 10
9.8
9.3
29.1
9.7a
V4 10
9.3
10
29.3
9.8a
V5 7.4
7.9
7.7
23.0
7.7d
V6 8.9
7.9
8.3
25.1
8.4cd
V7 9.5
10
10
29.5
9.8a
V8 10.2
9.7
9.3
29.2
8.7bc
V9 8.9
9.2
8.7
26.8
8.9bc
V10 8.7
10
9.1
27.8
9.3ab
V11 8.7
9.4
10
28.1
9.4ab
V12 9.1
8.6
8.3
26.0
8.7bc
V13 10.2
10.1
10
30.3
10.1a
TOTAL 120.3
119
118.7
358 9.17


ANALYSIS OF VARIANCE
SOURCE OF DEGREES OF
SUM OF
MEAN OF COMPUTED TABULAR F
VARIATION
FREEDOM
SQUARES SQUARES
Fc
0.05 0.01
Entry 12
23.219
1.935
10.49**
2.15
2.96
Error 24
4.795
0.184



TOTAL 28
28.014



**
–
highly
significant
Coefficient of Variation = 4.68 %






Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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76
Appendix Table 23. Number of Sproots per tuber of thirteen potato entries
ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 2
3
3
8
3
V2 2
3
3
8
3
V3 2
2
3
7
2
V4 3
3
3
9
3
V5 3
3
3
9
3
V6 2
3
3
8
3
V7 3
3
2
8
3
V8 3
2
3
8
3
V9 3
3
2
8
3
V10 3
3
3
9
3
V11 3
3
3
9
3
V12 3
3
3
9
3
V13 3
3
3
9
3
TOTAL 35
37
37
109
2.79


ANALYSIS OF VARIANCE
SOURCE OF DEGREES OF
SUM OF
MEAN OF COMPUTED TABULAR F
VARIATION
FREEDOM
SQUARES SQUARES
Fc
0.05 0.01
Treatment
12
11.744
0.979
2.04ns 2.15
2.96
Error 24
10.000
0.285



TOTAL 28
21.744



ns - not significant


Coefficient of Variation = 17.13 %





Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

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77
Appendix Table 24. Percent dry matter content of thirteen potato entries
ENTRY REPLICATION
TOTAL
MEAN
I
II
III

V1 17
17
17
51
17f
V2 22
22
22
66
22c
V3 26
26
26
78
26a
V4 23
25
25
73
24b
V5 22
23
22
67
22c
V6 20
20
20
60
20d
V7 22
22
22
66
22c
V8 20
21
21
62
20d
V9 21
21
21
63
21cd
V10 22
22
23
67
22c
V11 22
21
22
65
22c
V12 19
17
19
55
18e
V13 20
21
21
62
21cd
TOTAL






ANALYSIS OF VARIANCE
SOURCE OF DEGREES OF
SUM OF
MEAN OF COMPUTED TABULAR F
VARIATION
FREEDOM
SQUARES SQUARES
Fc
0.05 0.01
Entry 12
192.769
16.064
48.19**
2.15
2.96
Error 24
8.667
0.333



TOTAL 28
201.436



** – highly significant



Coefficient of Variation =2.70 %



Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in
Calasipan, Atok, Benguet / John Paul L. Sabiano. 2006

---

Document Outline

• Agronomic and Postharvest Characters of Potato Entries for Ware and Seed Tubers in Calasipan, Atok, Benguet
  • BIBLIOGRAPHY
  • ABSTRACT
  • TABLE OF CONTENTS
  • INTRODUCTION
  • REVIEW OF LITERATURE
  • MATERIALS AND METHODS
  • RESULTS AND DISCUSSION
  • SUMMARY, CONCLUSION AND RECOMMENDATION
  • LITERATURE CITED
  • APPENDIX

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