BIBLIOGRAPHY ALUMIT, GENESIS B, April ...
BIBLIOGRAPHY
ALUMIT, GENESIS B, April 2013. Characterization and Evaluation of
PotatoEntries for Organic Production System in La Trinidad, Benguet.Benguet State
University, La Trinidad, Benguet.
Adviser: Belinda A. Tad-awan, PhD.
ABSTRACT
The study was conducted to morphologically characterize the different potato
entries; determine the best performing entries under organic production; and to determine
the profitability of using the different potato entries under organic production.
Variation among the tuber skin color was observed. Tuber ranged from white
cream, red and brown. High dry matter content was obtained in all the entries except for
entry 306522. Entries 303223, 303405, 304416 and 307521 were acceptable based on their
sensory characteristics.
Potato entries 305185, 304416 and 306522 out yielded the other potato entries and
were observed resistant to late blight infection. These entries also obtained high return on
cash expense, therefore, recommended for organic production in La Trinidad, Benguet.
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
INTRODUCTION
The potato
(Solanum tuberosum L
.) is a high yielding short duration crop that
produces high dry matter and protein per unit area and unit time. In terms of quantity,
potatoes are the fourth on the list of the crop species after rice, wheat, and corn which are
important to human nutrition worldwide. Thus, potatoes have a great potential to meet the
increasing food demand worldwide. According to Perez
et al. (2006) potato is major cash
crop in highlands and mid elevation areas in Mindanao, because it has a short growing
period, a potential for high yield in a growing market for fresh and process potato. In
addition the total potato production comes from Benguet and Mountain Province is about
74 %, while the remaining 26% were from Southern and Northern parts of Mindanao
(PCARRD, 1997).
It is known that farmers in Benguet and Mountain Province use tremendous amount of
synthetic fertilizers and pesticides to increase their production, however, these practices as
claimed by researchers may lead to soil acidity, decrease population of natural enemies,
pollution of the soil, water, and air which may cause health hazards. In this case, alternative
production practices should be practiced. One of these practices is organic farming or
organic agriculture.
According to Petzoldt (2005) organic farming is a method of production that uses practices
or materials which are biologically enhancing to the soil and plants. The principle of
organic farming is to replenish and maintain long term soil fertility by providing the
optimal condition for biological activity. Encouraging the use of local resources, recycled
nutrient and maintaining Biodiversity that will minimize the occurrence of pests.
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
Potato is considered as one of the most important crops in Benguet, however, lack of
superior cultivars, the destruction caused by insect pest and the unavailability of good
quality seed tuber is a constraint as claimed by farmers.
Organic potato production needs a variety that is suitable to the environment, resistant
against pests, and diseases and high yielding. Resistant varieties can help the farmers not
to use synthetic insecticides and fungicides therefore, it is important to evaluate varieties
for organic production. Evaluation of potato for organic production should be conducted
to determine their adaptability and stability in terms of yield, resistance to pest and disease
and level of uniformity in the farmers field (Anon, 2005).
The study was conducted to:
1. morphologically characterize the different potato entries;
2. determine the best performing potato entries in terms of yield and resistance to
pests under organic production at La Trinidad, Benguet condition; and
3. determine the profitability of using the different potato entries under organic
production.
The study was conducted at Balili, Experimental Station, Benguet State University,
La Trinidad, Benguet from November 2012 to February 2013.
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
REVIEW OF LITERATURE
Significance of Varietal Evaluation
Thomson and Kelly in 1957 stated that testing of variety is essential, but after
testing, attention should be given because there is great difference in yield, size, ear lines
and others. It is only by several trials that the superior strains are found.
Cagampang and Lantican (1977) observed that the wise use of an improved and well
selected variety may result in tremendous increase in yield. But growing the wrong cultivar
may mean crop failure because of disease infection and diverse climatic condition.
Selection of suitable cultivars is an important is an important step in the farm
planning process but the availability of large number of variety makes the selection of a
variety for a given field is difficult. Also there are many aspects which have to be
considered before it is possible to make an opinion of which one of the available cultivar
well be the most suited for growing (Boesen
et al., 1997).
Varietal Evaluation of Potato under Organic Production
In the study of Gibson (2002) in La Trinidad, Granola, Igorota and CM 9 produced
the highest marketable yield with low bacterial wilt infection, while genotypes IP 84004.7
and 13.1.1 also produced comparable yield with the other genotypes but were highly
infected with bacterial wilt. The study recommended Granola, Igorota and CM9, for
planting under La Trinidad, Benguet during the dry season planting.
According to Gayomba (2006), genotype 13.1.1 had the highest canopy cover, highest
resistance to late blight and highest total yield. Genotype 13.1.1 also had the highest ROCE
for both seed and table potato production at Sinipsip, Buguias. Genotypes 38025.17,
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
676070, and 5.19.2.2 could be produced in the area since the genotypes were selected by
the farmers.
Montes and Tad-awan (2006) in their evaluation of potato varieties for organic production
found that CIP genotype IP 84007.67, 676070 and CIP 13.1.1 were resistant to late blight
at 60 and 75 DAP in Longlong La Trinidad. For seed tuber production, genotype 380251.17
produced the highest return on cash expense. Further, the farmer-cooperator selected
IP84007.67, 676089 and Ganza due to their high yield and resistance to late blight.
Potato accessions CIP 13.1.1, CIP 676089, CIP 380251.17, BSU 5.1.19.2.2 and CIP
676070 produced the highest tuber yield per hill across locations and planting seasons.
These accessions also showed resistant to late blight in all production sites (Tad-awan
et
al., 2007).
It has been found by Daproza (2009) in his study at Balili, La Trinidad that TPS 15 potato
progeny had the highest percent survival, while TPS 14 and TPS 11 potato progenies have
low percentage survival. Potato progenies TPS 15, TPS 12, TPS 16 were observed to be
vigorous and resistant to late blight. The highest yielding progeny was TPS 15 with 4,380
kg/ 15m2. TPS 15 produced the highest number of tuber per hill.
In a related study by Sawak (2010) in Buguias, Benguet, Ganza obtained the highest
percent survival, exhibited the tallest plant, highest canopy cover and highly vigorous
plants at 75 DAP. MLUSA 5, MLUSA 8 and Ganza were rated moderately resistant to
frost injury at 60 and 75 DAP. All of the entries were moderately resistant to leaf miner.
Ganza produced the heaviest marketable and non-marketable tubers and had highest return
on cash expenses (ROCE).
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
Mendoza (2011) evaluated seven progenies under organic production in La Trinidad,
Benguet. The result of the study showed that progeny 303617 had the highest total number
of potato tubers, while progeny 306521 produced the heaviest weight, but comparable to
progeny 306468 and 303610.
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
MATERIALS AND METHODS
Land Preparation
An area of 195 m2 was thoroughly prepared and further divided into three blocks. Each
block was subdivided into thirteen plots measuring 1m x 5m representing the thirteen
treatments.
Cultural Management Practices
Organic production practices were employed during the conduct of the study. BSU
Grower’s Compost was incorporated into the soil at the rate of 5kg/m2 one week before
sowing, while Vermi-compost was incorporated at hilling-up with a rate of 5kg/m2.
Weeding and irrigation were employed in order to maintain the vigorous growth of the
plants. Planting of marigold and other crops within the area were done for diversification
purpose and to reduce pest occurrence.
Planting Materials and Treatments
Potato seed tubers were used as planting material. The potato entries were selected from
the project “Variety evaluation, on farm trials and seed production of organic vegetable in
CAR”.
The treatments were as follows:
CodePotato Entries
E1 305185
E2 303223
E3 304416
E4 305182
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
E5 306468
E6 306521
E7 306522
E8 303224
E9 307251
E10 303203
E11 307521
E12 303405
E13 Phil 5.19.2.2
Experimental lay-out and Planting
The experiment was laid-out following the randomized complete block design
(RCBD)with three replications. Seed tubers were planted at a distance of 30cm x 30 cm.
Data gathered:
A. Morphological characters (CIP, 2001)
1. LeafCharacters
a. Leaf Dissection. This describes the degree of leaf dissection expressed as:
1
Undissected – entire leaves.
2
Pinatilobed – leaves with lobes extending almost to the midribs.
3
Scarcely dissected – leaves with terminal and primary lateral
leaflets only.
4
Weakly dissected – leaves with terminal and primary lateral
leaflets and some secondary interjected leaflets on the rachis.
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
5
Medium dissected – leaves with terminal and primary lateral
leaflets and interjected leaflets from the second to the fifth order
on the rachis.
6
Strongly dissected – leaves with terminal and primary lateral
leaflet, interjected of the second, third etc. Order on the rachis
and one to three interjected leaflets on the petiolules.
7
Very strong dissected – leaves with terminal and primary lateral
leaflet, intersected leaflets of the second, third, etc. Order on the
rachis and more than three interjected leaflets on the petiolules
and rachidules.
b. Adaxial leaf pubescence. This represents the degree to which the lower surfaces of the
leaves are covered by hairs (trichomes) expressed as:
0 Glabrous – when hairs are absent
1 Glabrescent – when the pubescence is very sparse
2 Pubescence
3 Strongly pubescent
c. Type of hairs (trichomes). This describes the type of hair in the lower surface of the
leaves expressed as:
0 Absent
1 Simple – simple trichomes.
2 Simple and Glandular – simple trichomes and glandular
trichomes bearing a sticky four 0 – lobed head.
3 Simple and Glandular – simple trichomes and glandular
trichomes with a sticky droplet at the tip.
4 Simple and Glandular – simple trichomes and both type of
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
glandular trichomes present.
2. Stem Character
a. Stem color. This indicates the color of the stems expressed as:
1 Green only
2 Red-brown only
3 Purple only
4 Cream with some red-brown
5 Cream with purple
6 Red-brown with some green
7 Purple with some green
8 Others
3. Tuber Characters
a. Predominant tuber skin color. These are the color which covers most of the surface
of the tuber expressed as:
1 White-cream
2 Yellow
3 Orange
4 Brownish
5 Pink
6 Red
7 Purple
9 Dark purple-black
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
b. Secondary tuber skin color. These describe the color on the surface of the tuber
expressed as:
0 Absent
1 White-cream
2 Yellow
3 Orange
4 Brownish
5 Pink
6 Red
7 Purplish-black
8 Purple
9 Dark purple-black
c. Tuber skin type. This is expressed as:
1 Smooth
2 Rough
3 Partially netted
4 Totally netted
5 Very heavily netted
6 Others
d. Pre-dominant tuber flesh color. This indicates the flesh color present in most of the tuber
expressed as:
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
1 White
2 Cream
3 Yellow-cream
4 Yellow
5 Red
6 Violet
7 Purple
8 Others
e. Secondary tuber flesh color. This represents the secondary flesh color in the tuber
expressed as:
0 Absent
1 White
2 Cream
3 Yellow-cream
4 Yellow
5 Red
6 Violet
7 Purple
f. General tuber shape. This indicates the tuber outline expressed as:
1
Compressed (oblate) – major axis is the shortest axis.
2
Round – an almost circular outline
3
Ovate – an outline resembling an egg. The broadest part
is within 1/3 of the distance from the stolon end.
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
4
Obovate – an outline which is inversely ovate and
broadest within 1/3 of the distance from the apical end.
5
Elliptic – an outline showing the same breadth when
measured at equal distance from both the stolon and
apical end. The outline is slightly acute at each end.
6
Oblong – an almost rectangular outline with the sides
nearly parallel but the corners rounded. The
length/breadth ratio should not be more than 3/2.
7
Long-oblong – an oblong outline with a length/breadth
ratio closer to 2/1.
8
Elongate – a long rectangular outline with a
length/breadth ratio equal to or more than 3/2.
g. Unusual tuber shape. This represent those variants of tuber shape which
cannot be described under general tuber shape and expressed as follows:
0
Absent
1
Flattened – when the length of a transverse section, at
any point of the tuber, is more than three times longer
than its breadth.
2
Clavate – resembling an elongated club, thickened at
one end.
3
Reniform – shaped like a kidney.
4
Fusiform – spindle-shaped, tapering gradually at both
ends.
5
Falcate – curved or shaped like a sickle or horseshoe.
6
Spiral – long and coild.
7
Digitate – resembling a hand or a fist.
8
Concertina-shaped – resembling a concertina.
9
Tuberosed – covered with few or many small lamps and
tubers. It includes those shaped, like a pineapple, a
cluster of grapes, and raised internodes.
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
h. Depth of tuber eyes. This indicates the depth of the eye in the tuber expressed
as:
1 Protruding
2 Shallow
3 Medium
4 Deep
5 Very deep
i. Eyes per tuber. This represents the number of eyes expressed as:
1 Few (less than 5)
5 Intermediate
10 Many (more than 20)
B.Growth Characters
1. Plant survival (%). The number of plants that survived were counted at 30, 60
and 75 days after planting(DAP) and calculated using the formula:
Number of plants survived
% Survival = x 100
Total number of plants planted
2. Plant height. Plant height was measured at 30, 60, and 75 DAP using a meter
stick.
3. Canopy cover. Canopy cover was recorded at 30, 60, and 75 DAP using a
wooden frame which measures 120 cm x 60 cm and having an equal size of grid of 12 cm
x 6 cm grids. Holding the grids over the foliage of four marked plants, grids covered with
effective leaves will be counted.
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
4. Plant vigor. Plants were rated at 30, 60, and 75 DAP based on a rating scale by
(CIP, 2001):
Scale Description Reaction
5 Plant is strong with robust stems and Highly Vigorous
leaves, light color to dark green in color.
4 Plants are moderately strong with robust Moderately Vigorous
stem and leaves were light green.
3 Better than less vigorous. Vigorous
2 Plants are weak with few thin stems and Less Vigorous
leaves pale.
1 Plants are weak with few stems and leaves, Poor Vigorous
very pale.
C. Yield and Yield Components
1. Number and weight of marketable tubers per plot (kg). All the tubers that were
of marketable size, not malformed, free from cuts cracks and without more than 10%
greening of the total surface was counted and weighed at harvest.
2. Number and weight of non-marketable tubers per plot (kg). This was obtained
by counting and weighing all tubers that are malformed, damage by pest and disease and
those with more than 10% greening.
3. Total yield per 5m2(kg). This is the sum of the weight of marketable and non-
marketable tubers per plot.
4. Computed Yield (t/ha). This was computed using the formula:
Total Yield
Computed Yield (t/ha) = x 10,000
Plot Size (m2/1,000)
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
D. Cost and Return Analysis. The cost of production, gross sale, net profit, and return on
cash expense were determined, Return on cash expense was computed by using the
formula:
Net Income
Return on Cash Expense = x 100
Total Cost of Production
E. Reaction to Pest and Diseases
1. Reaction to leaf miner. The reaction to leaf miner was recorded at 30, 60,
75 DAP using the following rating scale (CIP, 2001):
ScaleDescriptionReaction
1 Leaf infected (1-20%) Highly Resistant
2 Infected (20-40%) Moderately Resistant
3 Moderately infected (41-60%) Susceptible
4 Severely infected (61-80%) Moderately Susceptible
5 Most serious (81-100%) Very Susceptible
2. Reaction to late blight. Rating was done at 30, 60, and75 DAP using a rating
scale (CIP, 2001) as follows:
%Blight
Scale
Description
0
1
No blight observed
Traces-<5
2
Blight is present at maximum of 10 lesions per
plot.
5-<15
3
Plant look healthy but lesions are easily seen at
closer distance. Maximum foliage is one
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
affected by lesions or destroyed corresponds to
more than 2 leaflets.
15->35
4
Blight easily sees on most plants. About 25%
foliage is covered with lesions or destroyed.
35->65
5
Plots looks green; however all plants are
affected. Low leaves are dead and about 1/2 of
the foliage are destroyed.
65-<85
6
Plots look green with brown flocks about 75%
each plant is affected. A left or lower half of the
plant is destroyed.
85->95%
7
Plant is either predominant green or brown only
top leaves are green.
95-<100
8
Plots colored brown. A few top leaves have
green areas. Most stems leave lesions are dead.
100
9
All leaves and stems are dead.
Description: 1-highly resistant, 2-3- resistant, 4-5- moderate resistant, 6-7- moderate
susceptible, 8-9- susceptible
F. Postharvest Characters
1. Dry matter content of tubers. Twenty gram of tubers was weighed and sliced
into cubes and oven dried at 800C for 24 hrs. This was recorded and computed using the
following formula:
Dry mattercontent (%) = 100% - % moisture content
Fresh weight – Oven dry weight
Where: % Moisture Content =
x 100%
Fresh weight
2. Sugar Content (0Brix). This was taken by extracting the juice of 20 g potato
tubers and read on a digital refractometer.
3. Sensory Evaluation. Storage roots harvested were washed and boiled and evaluated by
fifteen evaluators compressed of faculty members and students. Evaluation was based in
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
terms of appearance, color, texture, flavor and general acceptability following the 1-5 scale.
This was the basis to determine the eating quality.
Rating Description
1 Dislike very much
2 Dislike moderately
3 Neither like nor dislike
4 Like moderately
5 Like very much
G. Agro-climatic Data.
Temperature, relative humidity, rainfall were recordedduring the conduct of study.
Data Analysis
All quantitative data were analyzed using the Analysis of Variance (ANOVA) for
Randomized Complete Block Design (RCBD) with three replications. The significance of
difference among the treatment means was tested using the Duncan’s Multiple Range Test
(DMRT) at 5% level of significance.
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
RESULTS AND DISCUSSION
Meteorological Data
Table 1 shows the monthly mean temperature, relative humidity, rainfall and sunshine
duration during the conduct of study. The monthly mean temperature ranged from 13.1 0C
to 23 0C. During the month of January, air temperature was the highest. The lowest relative
humidity was noted in the month of November with 84.75%, while the highest was noted
in the month of December with 86.5%. Very little rainfall was noted (0.15 to 2.19 mm).
The temperature and relative humidity during the conduct of study was favorable.
Temperature is important in potato plants because it enhance the accumulation of
carbohydrates and dry matter in the tubers. The optimum temperature for potato production
was reported to be ranging from 17-22 0C and a relative humidity of 86% (HARRDEC,
1996). The lowest sunshine duration was noted in the month of November at 11.09 min
while the highest was observed in the month of January with 360 min.
Table 1. Meteorological data from October 2012 to January 2013
TEMPERATURE
RELATIVE
RAINFALL
SUNSHINE
MONTH
(0C)
HUMIDITY
(mm)
DURATION
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
MIN MAX
(%)
(min)
October
15.1 23.00
85
2.19
11.09
November 13.1 20.9
84.75
1.33
10.97
December 13.2 22.6
86.5
0.15
12.18
January
18.3 23.7
80
0.5
360
Morphological Characters
Leaf Dissection, Adaxial Leaf Pubescence
Type of Hair and Stem color of the potato
entries
Generally, all the entries had similar characteristic. For the leaf dissection, all the entries
were scarcely dissected having terminal and primary lateral leaflet only (Figure 1). In terms
of adaxial leaf pubescence, all the entries had strongly pubescence where the upper surface
of the leaves is covered with fine short hairs or trichomes only and simple and glandular
for the type of hair. For the stem color, all the entries are colored green.
Pre-dominant and Secondary tuber skin color
Pre-dominant and Secondary tuber flesh color
Table 2 shows the tuber characters of the entries. In terms of pre-dominant tuber skin color,
entries 303224 and 303405 presented a white cream and red color. Brownish tubers were
observed in entries 305185 and 306522. The rest of the entries displayed white cream color.
For the secondary tuber skin color, all the entries displayed a white cream color.
In terms of tuber flesh color, all the entries showed a white color except for entry 307251
with yellow color, while absent in terms of secondary flesh color.
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
The tuber skin color can be used as a selection index for gourmet potato in which yellow
and white cream color is acceptable for potato chipping (Ludwig, 1985).
306522 304416
305185 303223
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
303224 306521
Figure 1. Leaves of some potato entries
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
Table 2. Pre-dominant skin color, secondary skin color, pre-dominant flesh color and
secondary flesh color of the thirteen potato entries evaluated for organic production.
ENTRY
PRE-
SECONDARY SKIN
PRE-
DOMINANT
COLOR
DOMINANT
SKIN COLOR
FLESH COLOR
305185
Brownish
White-cream
White
303223
White-cream
White-cream
White
304416
White-cream
White-cream
White
305182
White-cream
White-cream
White
306468
White-cream
White-cream
White
306521
White-cream
White-cream
White
306522
Brownish
White-cream
White
303224
White-cream
White-cream
White
and Red
307251
White-cream
White-cream
Yellow
303203
White-cream
White-cream
White
307521
White-cream
White-cream
White
303405
White-cream
White-cream
White
and Red
Phil 5.19.2.2
White-cream
White- cream
White
Tuber skin, Tuber shape, Depth of eye
and Eyes per Tuber
In terms of tuber skin type, entries 303223, 304416, 306521, 306522 and 307251 exhibited
a rough skin, while the rest of the entries had smooth skin texture. In terms of shape, entries
305185 and 303224 exhibited oblong and round shape, Phil 5.19.2.2 had an obovate and
oblong shape. The rest of the entries had oblong shape. There were no un-usual tuber
shapes (Table 3 and Fig. 2).
For the depth of tuber eyes, protruding and shallow eyes were observed in entries 306521
and Phil 5.19.2.2, while entries 304416 and 305182 had protruding eyes. The rest of the
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
entries were shallow. In terms of the number of eyes, all the entries were observed to be
intermediate, ranging from 6 to 20 eyes per tuber.
In relation to potato processing, shallow eyes, round or elongate shape, smooth skin and
freedom from defect are among the external characteristics of potatoes preferred by the
processor. These characteristics are important for lesser trimming (Ludwig, 1985).
Table 3. Tuber skin type, tuber shape, depth of tuber eye and number of eyes per tuber of
the thirteen potato entries
ENTRY
TUBER
TUBER SHAPE
DEEP OF
EYES PER TUBER
SKIN
EYE
305185
Smooth
Round and
Shallow
Intermediate
Oblong
303223
Rough
Oblong
Shallow
Intermediate
304416
Rough
Oblong
Protruding
Intermediate
305182
Smooth
Oblong
Protruding
Intermediate
306468
Smooth
Oblong
Shallow
Intermediate
306521
Rough
Oblong
Protruding
Intermediate
306522
Rough
Oblong
Shallow
Intermediate
303224
Smooth
Round and
Shallow
Intermediate
Oblong
307251
Rough
Oblong
Shallow
Intermediate
303203
Smooth
Oblong
Shallow
Intermediate
307521
Smooth
Oblong
Shallow
Intermediate
303405
Smooth
Oblong
Shallow
Intermediate
Phil
Smooth
Obovate and
Protruding
Intermediate
5.19.2.2
Oblong
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
Figure 2. Tubers of some potato entries
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
Growth Characters
Plant Survival. The percent survival of the thirteen potato entries was not significant at 30,
60 and 75 DAP. At 60 DAP, all entrieshad decrease in their plant survival due to late blight
infection. Among the entries, high percentage plant survival was observed on entry 304416
with 81.89% which is comparable to entries 305185 and 30652, while the lowest was
observed on entry 303224 with 44.02%.
At 75 DAP, entry 305185 exhibiteda high plant survival of 76.00% which is not
significantly different with entry 306522 with72.73%.
Potato entries 305185, 304416 and 306522 with more than 50% survival may be due to its
resistant to late blight.
Table 4. Plant survival of the thirteen potato entries evaluated for organic production at 30,
60 and 75 DAP
PLANT SURVIVAL (%)
ENTRY 30 DAP 60 DAP 75 DAP
305185
100.00
80.95ab
76.00a
303223
100.00
46.53c
43.40b
304416
100.00
81.89a
66.64ab
305182
96.38
52.80bc
52.91ab
306468
97.81
59.35abc
57.20ab
306521
98.78
58.09abc
55.71ab
306522
100.00
76.06ab
72.73a
303224
100.00
44.02c
44.02b
307251
100.00
53.40bc
53.40ab
303203
98.89
61.62abc
55.72ab
307521
95.39
59.54abc
57.06ab
303405
97.92
63.29abc
55.00ab
Phil 5.19.2.2
95.02
68.95abc
64.07ab
CV%
2.27
22.80
21.18
Means with the same letter are not significantly different at 5% level by DMRT.
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
Plant Height
Table 5 shows the heights of the potato entries at 30, 60 and 75 DAP. At 30 DAP. No
significant differences were observed.
At 60 and 75 DAP, significant differences were observed. At 60 DAP, entry 307521 had
the tallest plants with 63.67 cm, but comparable with entries 304416 and 306522, while
the shortest plant were observed in Phil 5.19.2.2 with 49.40 cm.
At 75 DAP, the tallest plants were observed in entry 306522 with 65.40 cm, while the
shortest plant were observed in Phil 5.19.2.2 with 52.67 cm.
Increasing height and variability are observed among the potato entries. According to
Smith (1968) as cited by Gayodan (1999), larger and longer stems were found to have
greater assimilation rate per unit plant and leads to higher yield.
Table 5. Plant height of the thirteen potato entries evaluated for organic production at 30,
60 and 75 DAP
PLANT HEIGHT(CM)
ENTRY
30 DAP
60DAP
75DAP
305185
38.53ab
52.87bc
55.00bc
303223
38.73ab
49.93c
54.53c
304416
37.67ab
60.40ab
62.73ab
305182
34.33b
50.13c
53.93c
306468
38.87ab
49.73c
54.33c
306521
39.07ab
53.20bc
54.67c
306522
37.80ab
60.60ab
65.40a
303224
39.80ab
56.47abc
59.67abc
307251
42.13a
53.93bc
54.87bc
303203
42.07a
55.13abc
58.40abc
307521
40.47ab
63.67a
64.80ab
303405
40.60ab
52.27bc
53.73c
Phil 5.19.2.2
40.60ab
49.40c
52.67c
CV (%)
9.74
8.73
8.87
Means with the same letter are not significantly different at 5% level by DMRT.
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
Canopy Cover
Table 6 shows, significant differences on the canopy cover of the thirteen potato entries at
30, 60 and 75 DAP. Wide canopy was observed in entry 306522 with 73.11, but not
significantly different with entries 305185, 306521, 303224 and 303405 at 30 DAP. Lowest
canopy cover was observed from entry 307521 with 44.33.
Entries 304416 and 306522 had the widest canopy cover at 60 DAP of about 81.00 and
84.78, respectively, but comparable with entry 305185 with 71.33. Lowest canopy was
observed in Phil 5.19.2.2 with 36.11.
At 75 DAP, wide canopy was still observed on entries 304416 and 306522 with 39.22 and
40.55, respectively, but comparable with entry 305185. Narrowest canopy was still
observed in Phil 5.19.2.2 with 17.44.
Potato entries 305185, 304416 and 306522 exhibitedthe widest canopy in all dates. This
might be due to their resistance to late blight, high plant survival and plant vigor.
Table 6. Canopy cover of the thirteen potato entries evaluated for organic production at 30,
60and 75 DAP
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
CANOPY COVER
ENTRY
30 DAP
60DAP
75DAP
305185
70.22a
71.33ab
37.11ab
303223
55.55ab
49.77bc
26.33abc
304416
56.55ab
81.00a
39.22a
305182
58.00ab
47.33bc
23.78bc
306468
59.00ab
64.44abc
28.44abc
306521
66.55a
68.22ab
28.67abc
306522
73.11a
84.78a
40.55a
303224
67.77a
45.44bc
19.55c
307251
56.77ab
42.66bc
17.11c
303203
59.78ab
45.55bc
19.09c
307521
44.33b
56.66abc
24.33bbc
303405
62.11a
44.77bc
18.44c
Phil 5.19.2.2
59.44ab
36.11c
17.44c
CV (%)
14.14
26.79
28.09
Means with the same letter are not significantly different at 5% level by DMRT.
Plant Vigor
Table 7 shows, the plant vigor of the thirteen potato entries at 30, 60 and75 DAP. All entries
at 30 DAP were rated highly vigorous. At 60 DAP, entry 304416 and 306522 were rated
moderately vigorous, while the entries 305182, 305185, 306468, 306521, 307521 and Phil
5.19.2.2 were rated vigorous. Other entries were rated less vigorous.
At 75 DAP most of the entries were rated either less vigorous or poor except for the entries
304416, 306522 and 305185 which were rated vigorous.
Table 7. Plant vigor rating of the thirteen potato entries evaluated for organic production
at 30, 60 and 75 DAP
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
PLANT VIGOR
ENTRY
30 DAP
60 DAP
75DAP
305185
Highly vigorous
Vigorous
Vigorous
303223
Highly vigorous
Less vigorous
Less vigorous
304416
Highly vigorous
Moderately vigorous
Vigorous
305182
Highly vigorous
Vigorous
Less vigorous
306468
Highly vigorous
Vigorous
Less vigorous
306521
Highly vigorous
Vigorous
Poor vigorous
306522
Highly vigorous
Moderately vigorous
Vigorous
303224
Highly vigorous
Less vigorous
Less vigorous
307251
Highly vigorous
Less vigorous
Less vigorous
303203
Highly vigorous
Less vigorous
Less vigorous
307521
Highly vigorous
Vigorous
Less vigorous
303405
Highly vigorous
Less vigorous
Less vigorous
Phil 5.19.2.2
Highly vigorous
Vigorous
Poor vigorous
Yield and Yield Components
Number of Marketable and
Non-marketable Tubers
Table 8 shows no significant differences on the number of marketable and non-marketable
tubers per plot. However, entries 303223 and 303224 produced the most numbers of
marketable tubers of 138 and 137, respectively, while entry 303405 had the least number
of marketable tubers of 73. For the non-marketable tubers entry 303203 had the lowest
number of non-marketable tuber of 4.67.
Weight of Marketable and
Non- marketable tubers
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
Highly significant differences were observed on the marketable and non-marketable yield
(Table 8). Entry 305185 obtained the heaviest marketable tuber of 4.43 kg which is
comparable with entry 306522. Lightest marketable tubers were obtained from entry
303405. In terms of non-marketable weight, entries 303223 and Phil 5.19.2.2 had the
lowest non-marketable weight of 0.11 and 0.11 kg, respectively.
Table 8.Number and weight of marketable tubers, number of non-marketable and weight
of non-marketable tubers evaluated under organic production at 30, 60 and 75 DAP
MARKETABLENON-MARKETABLE
ENTRY
NUMBER
WEIGHT
NUMBER
WEIGHT
(Kg/5m2)
(Kg/5m2)
305185
101.7ab
4.43a
6.33abc
0.22bcd
303223
138.00a
3.58abcd
4.67a
0.11a
304416
99.33ab
3.76abc
7.33abc
0.20bcd
305182
97.33ab
1.65ef
8.67abc
0.16cd
306468
96.33ab
2.44cdef
6.67abc
0.23bcd
306521
112.00ab
3.59abc
5.67abc
0.21bcd
306522
75.33b
4.22ab
7.00abc
0.35d
303224
137.00a
3.03abcde
9.33ab
0.29ab
307251
109.3ab
2.87bcdef
8.67abc
0.28abc
303203
78.33b
1.92def
9.67c
0.32ab
307521
119.3ab
2.32cdef
8.33abc
0.20bcd
303405
73.00b
1.52f
7.67abc
0.20bcd
Phil 5.19.2.2
117.3ab
2.45cdef
5.33bc
0.11a
CV (%)
23.76
25.67
28.46
28.78
Means with the same letter are not significantly different at 5% level by DMRT
Total and Computed yield
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
Table 9 shows highly significant differences on the total yield and computed yield of the
thirteen potato entries. Entry 305185 significantly had the highest total yield of 4.65 kg/m2
and computed yield of 9.30 t/ha, but comparable with entry 306522. Second in rank were
entries 304416 and 306521.
The high yield of the entries 305185, 304416 and 306522 may be attributed to their
resistance to late blight, high canopy cover and vigor.
Table 9. Total and computed yield of the potato entries evaluated under organic
production at 30, 60 and 75 DAP
ENTRY
TOTAL YIELD
COMPUTED YIELD
(kg/m2)
(t/ha)
305185
4.65a
9.30a
303223
3.50abcd
7.00abcd
304416
3.97abc
7.94abc
305182
1.82ef
3.65ef
306468
2.67cdef
5.34cdef
306521
3.80abc
7.60abc
306522
4.58ab
9.16ab
303224
3.33abcde
6.66abcde
307251
3.15abcdef
6.31abcdef
303203
2.24def
4.49def
307521
2.53cdef
5.06cdef
303405
1.72f
3.44f
Phil 5.19.2.2
2.57cdef
5.14cdef
CV (%)
23.81
23.81
Return on Cash Expenses (ROCE)
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
Cash expense of potato entries is shown in Table 10. Higher return on cash expense was
obtained from the entries 305185, 306522 and 304416.
Table 10. Cost and return analysis of the potato entries for organic production
COST OF
MARKETABLE
GROSS
NET
ENTRIES
PRODUCTION
TUBERS
SALE
INCOME ROCE
(Php)
(Kg/5m2)
(Php)
(Php)
305185
413
13.29
797.40
384.40
93.08
303223
413
10.14
608.40
187.00
45.27
304416
413
11.28
676.80
263.00
63.68
305182
413
4.95
292.00
-121.00
-32.44
306468
413
7.32
439.20
26.20
6.34
306521
413
10.77
646.20
233.20
43.63
306522
413
12.66
759.60
346.60
83.92
303224
413
9.09
545.40
132.40
32.05
307251
413
8.61
516.60
103.60
25.08
303203
413
5.76
345.60
-674.00
-63.19
307521
413
6.96
417.60
4.60
1.11
303405
413
4.56
273.60
-139.40
-33.75
Phil 5.19.2.2
413
7.33
441.10
28.10
6.80
* Total cost of production includes material inputs and labor cost.
* Selling price of potato tuber was 60 pesos per kilo.
Reaction to Leaf Miner and Late Blight
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
Leaf Miner Incidence.Leaf miner incidence with in the area was not observed. This could
be due to the planting of marigold which acted as insect repellant and the maintenance of
plant diversity in the experimental area.
Late Blight Infection. Table 11 shows the reaction to late blight of the thirteen potato entries
at 30, 60 and 75 DAPS. It was observed that all the entries were highly resistant at 30 DAP.
However, an increase in late blight were rated as moderately susceptible except for the
entries 305185, 304416 and 306522 which rated were moderately resistant.
The sudden increase in late blight infection at 60 DAP could be due to high relative
humidity caused by sudden rain showers in November and December.
Table 11. Late blight rating of the potato entries evaluated for organic production at 30,
60 and 75 DAP
REACTION TO LATE BLIGHT
ENTRY
30 DAP
60 DAP
75 DAP
305185
Highly resistant
Moderately resistant
Moderately resistant
303223
Highly resistant
Moderately susceptible
Moderately susceptible
304416
Highly resistant
Moderately resistant
Moderately resistant
305182
Highly resistant
Moderately susceptible
Moderately susceptible
306468
Highly resistant
Moderately susceptible
Moderately susceptible
306521
Highly resistant
Moderately susceptible
Moderately susceptible
306522
Highly resistant
Moderately resistant
Moderately resistant
303224
Highly resistant
Moderately susceptible
Moderately susceptible
307251
Highly resistant
Moderately susceptible
Moderately susceptible
303203
Highly resistant
Moderately susceptible
Moderately susceptible
307521
Highly resistant
Moderately susceptible
Moderately susceptible
303405
Highly resistant
Moderately susceptible
Moderately susceptible
Phil 5.19.2.2
Highly resistant
Moderately susceptible
Moderately susceptible
Postharvest Characters
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
Sugar content. Table 12 shows significant difference on the sugar content of the potato
entries. Entry 303223 produced tuber with highest sugar content of 3.83 0 Brix which is
comparable with entry 307521 with 3.70 0 Brix.
Sugar content is apparently important in potato chips processing, low sugar content
emphasizes good quality for potato chipping and prevents darkening on chips (Table 12).
Dry matter content. Dry matter content of the potato entries ranges from 15.00to 25.00%.
Entry 307521 had significant the highest dry matter content of 25.00% but comparable
with entry 303203 with 23.33%, while entry 306521 had the lowest dry matter content of
15.00% (Table 12).
The percent dry matter indicates the solid matter that comprises the tuber which is very
important composition of the potato. Based on the findings of NPRCRTC(2003), dry
matter content is variable depending on the planting season, fertilization and maturity
among other factors. In this study, the high dry matter content of the potato entries could
be due to the favorable dry season planting from October to January.
Table 12. Sugar content and dry matter content of the thirteen potato entries under organic
production
ENTRY
SUGAR CONTENT
DRY MATTER CONTENT
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
(0Brix)
(%)
305185
3.47cd
21.67ab
303223
3.83a
18.33bc
304416
3.50cd
18.33bc
305182
3.33def
16.67cd
306468
3.60bc
18.33bc
306521
3.40de
18.33bc
306522
3.40de
15.00d
303224
3.23ef
16.67cd
307251
3.43cd
16.67cd
303203
3.50cd
23.33ab
307521
3.70ab
25.00a
303405
3.37def
16.67cd
Phil n5.19.2.2
3.20f
21.67ab
CV (%)
2.87
1.02
Mean with the same letter are not significantly different at 5% level by DMRT
Sensory Evaluation of the Thirteen
Potato Entries for Organic Production
As shown in Table 13, entries 303203, 304416 and 307251 were rated liked moderately
while the rest of the entries were rated neither liked nor disliked in terms of appearance.
For color, entries 303203, 303223 and 304416 were liked moderately, while the rest were
rated neither liked nor disliked.
In terms of texture, entries 306521 and 307521 rated liked moderately, while the other
entries were rated neither liked nor disliked. For the flavor, entries 303223, 303405 and
304416 are liked moderately, while the rest of the entries are neither liked nor dislike. In
terms of general acceptability, entries 303223, 303405, 304416 and 307521 were liked
moderately, while the other entries rated as neither like nor dislike.
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
The entries that were rated liked moderately were acceptable as to their sensory
characteristics by the evaluators.
Table 13.Sensory evaluation of the thirteen potato entries evaluated for organic production
at 30,60 and 75 DAP
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
ENTRY
APPEAR
COLOR
TEXTURE
FLAVOR
GENERAL
ANCE
ACCEP-
TABILITY
305185
Neither liked nor
Neither liked Neither liked Neither liked Neither liked nor
disliked
nor disliked
nor disliked
nor disliked
disliked
303223
Neither liked nor
Liked
Neither liked
Liked
Liked moderately
disliked
moderately
nor disliked
moderately
304416
Liked moderately
Liked
Neither liked
Liked
Liked moderately
moderately
nor disliked
moderately
305182
Neither liked nor
Neither liked Neither liked Neither liked Neither liked nor
disliked
nor disliked
nor disliked
nor disliked
disliked
306468
Neither liked nor
Neither liked Neither liked Neither liked Neither liked nor
disliked
nor disliked
nor disliked
nor disliked
disliked
306521
Neither liked nor
Neither liked
Liked
Neither liked
Neither like nor
disliked
nor disliked
moderately
nor disliked
dislike
306522
Neither liked nor
Neither liked Neither liked Neither liked
Neither like nor
disliked
nor disliked
nor disliked
nor disliked
dislike
303224
Neither liked nor
Neither liked Neither liked
Neither like
Neither like nor
disliked
nor disliked
nor disliked
nor dislike
dislike
307251
Neither liked nor
Neither liked Neither liked
Neither like
Neither like nor
disliked
nor disliked
nor disliked
nor dislike
dislike
303203
Liked moderately
Liked
Neither liked
Neither like
Neither like nor
moderately
nor disliked
nor dislike
dislike
307521
Liked moderately
Neither liked
Liked
Neither like
Like moderately
nor disliked
moderately
nor dislike
303405
Neither liked nor
Neither liked Neither liked
Like
Like moderately
dislike
nor disliked
nor disliked
moderately
Phil 5.19.2.2
Neither liked
Neither liked Neither liked
Neither like
Neither like nor
nor dislike
nor dislike
nor disliked
nor dislike
dislike
SUMMARY, CONCLUSIONS AND RECOMMENDATIONS
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
Summary
The study was conducted to: morphologically characterize the different potato entries;
determine the best performing entries under organic production; and determine the
profitability of using the different potato entries under organic production.
For the leaf dissection, all the entries were scarcely dissected, with strongly pubescence of
leaves and green stems. As to skin of the tubers, entries 305185 and 306522 had brownish
skin color, entries 303224 and 303405 had a white-cream and red color, while the rest of
the entries had white-cream in color. For the pre-dominant tuber flesh color, all entries
colored white except for entry 307251 with yellow color while no secondary flesh color
was observed.
There were no significant differences observed on the plant survival of the thirteen potato
entries, however, entries 305185, 304416 and 306522 exhibited high percentage survival
in all dates.All the entries had increase in their height in all the dates. Entry 306522
registered the tallest plants among the entries.As to canopy cover, at 60 and 75 DAP,
significant differences were observed where entries 304416 and 306522 had the widest
canopy covers
In terms of plant vigor, all the entries are highly vigorous at 30 DAP. Entries 304416 and
306522 were moderately vigorous while entries 305185, 305182, 306468, 306521, 307521
and Phil 5.19.2.2 were vigorous at 60 DAP. At 75 DAP, entries 304416, 306522 and
305185 were vigorous.
There was no occurrence of leaf miner during the conduct of the study. For late blight
infection, all the entries were highly resistant at 30 DAP. At 60 and 75 DAP, entries
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
305185, 304416 and 306522 were moderately resistant while the rest of the entries were
moderately susceptible to late blight.
Based on yield, entry 305185 produced the highest marketable yield which is comparable
with entry 306522. Lowest yield was observed from entry 303405.
For the sugar content and dry matter content, entry 303223 had the highest sugar content.
Entry 307521 had the highest dry matter content which is comparable with entry 303203.
The most profitable entries for organic production based on ROCE were 305185, 304416
and 306522.
For the sensory characteristic, evaluators rated the potato entries as liked moderately and
liked nor disliked in terms of appearance, color, texture, and flavor. For the general
acceptability entries 303223, 304416, 307521 and 303405 were moderately accepted by
the evaluators while the other entries were rated neither like nor dislike.
Conclusions
The different potato entries varied only in their tuber skin color. Other characters such as
stem and leaf characters, tuber flesh color are the same for all the potato entries. All the
entries producedyield under organic production system. Entries 305185, 304416 and
306522 are the most resistance to late blight infection. Entries 305185, 304416 and 306522
are the highest yielders under organic production. Entries 303223, 304416, 307521 and
303405 were moderately liked by the evaluators. Entries 305185, 3054416 and 306522
were the most profitable under organic production systems.
Recommendations
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
Based on the result of the study, potato entries 305185, 304416 and 306522 are
recommended for organic production in La Trinidad, Benguet. It is further recommended
that another study will be conducted during the wet season since the study was conducted
during the dry season to verify the results and determine the stability of the entries.
Characterization and Evaluation of PotatoEntries for Organic Production System in La
Trinidad, Benguet | ALUMIT, GENESIS B, April 2013
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