Ethnobotanical Leaflets 11: 113-121.
2007. Characterization
Studies and Yield Attributes of Some Varieties of Cowpea (Vigna
unguiculata L.) Alege, G. O. and
Mustapha, O. T.* Department of Plant
Biology, *Corresponding
Author: Oba Mustapha otiem787@yahoo.com Issued ABSTRACT Investigations were
carried out on sixteen improved varieties of cowpea (Vigna unguiculata L walp) obtained from International Institute for Tropical
Agriculture, INTRODUCTION Differences between individual organisms have two causes: variation in the genetic material which all organisms possess and which is passed from generation to generation; and variation caused by environmental influence on each individual organism (Elrod and Stansfield 2003). Heritable variation is the raw material for both natural and artificial selection and is ultimately therefore the basis for all observable biodiversity. Genetic diversity is particularly important for agricultural productivity and development (Fadconer, 1989). Cowpea contains about 25% protein, making it extremely valuable where many people cannot afford protein food such as meat and fish (IITTA 2002). Hall (2003), Ogbuiya (1997) and Adams (2003) also reported on the various uses to which different parts of cowpea can be put to. As reported by IITA (2002), the fast growth and spreading habit of traditional cowpea ensures maturity at the end of the rainy season, spreading the harvesting operation overtime and enable better and efficient use of family labour. Johnson et. al. (1955) reported that it is very important in any breeding programme to select and evaluate varieties for quantitative and yield ability before such varieties can be introduced to a given local environment. The aim of this work is, therefore, to characterize these improved varieties and evaluate the yield with a view to determining the best variety(ies) for introduction into the locality where the experiment was conducted. MATERIALS Sixteen different
improved varieties of cowpea (Vigna ungiculata) seed were obtained from International
Institute for Tropical Agriculture (IITA), |
|
The work was carried out on a plot of land in the
RESULTS Table 1 shows coefficient of variation for characters studied and it was observed to be high for number of branches per plant, number of leaves per plant, number of seeds per pod and number of pod per plant ie. 34.13%, 34.00%, 31.61% and 31.21% respectively. This implies that the varieties were different from one another in terms of leaves, branches, seed and pod producing ability but low coefficient of variation was observed for characters such as pod length and pod diameter (13.10% and 12.28% respectively). The finding agrees with Wien and Ackah’s (1978) conclusion. Result of qualitative characters studied showed that there are differences among the cowpea varieties (Table 2). This indicates that these varieties were of distinct genotype. Dulley and Moll (1969) stated that varieties of different qualitative characters are of distinct genotype and may breed for the manifestation of different traits in crop improvement. Correlation Coefficient (Table 3) showed that there is a strong positive correlation between leave number and stem diameter and also a positive correlation between leaf number and number of seeds per pod. This implies that the more the number of leaves, the wider the stem girth and the more the number of seeds produced per pod on each plant. There also exists positive correlation between number of branches and height. According to Falconer (1989), the phenotypic variability of quantitative traits in a population usually has an environmental component. So, it is inferred that those characters with positive correlations are influenced and controlled by similar gene combinations and environmental factors. There existed a negative correlation between pod number and number of seeds per pod. This implies that the more the pods on a plant, the less the number of seeds in a pod. So improvement on number of pod may contribute adversely to the number of seeds in such pods. This is in line with Dhagat et. at. (1978) who opined that negative genotypic correlation between characters selected for in breeding programme may result in reduction in the rate of improvement that could be attained if the correlation were positive or non-existing. Analysis of variance table showed that there are significant differences in all the characters studied among the varieties. This is an indication that genetic variability existed for all the quantitative characters analyzed. This is because the basis of any crop improvement is the availability of genetic variability within a population (Henry 2004). Multiple comparison for all the vegetative characters studied have shown that IT99K – 1122 had the highest means for three out of the four vegetative traits analyzed i.e height of plant, leaf number, and number of branches. IT99K – 429-2 had highest stem diameter (Table 4). This shows that these varieties (IT99K-1122 and IT99K-429-2) are the most adapted in term of vegetative performance in the environment of study. Faluyi (1978) stated that cowpea varieties with better vegetative characters can be used in the tropics for controlling erosion and as animal feeds. IT99K-316-2, which had the least mean values for leave number and stem diameter, is the least adapted variety in term of vegetative characters. These two varieties are recommended if the purpose of planting is for their vegetative parts. IT97K-461-4, IT98K-506-1, IT99K-529-1 and IT99K-1122 had highest mean values which were significantly different from every other variety in term of pod number, pod length, pod diameter and seed per pod respectively (Table 5). This indicated that the four varieties were of outstanding performance in term of yield attributes. IT 99K-1122, though had least mean number of pod per plant, it distinguished itself by been significantly different from others in term of mean member of seeds per pod. In conclusion, this
work revealed the existence of genetic variability among the sixteen improved
cowpea varieties studied. The work has
also helped to select, evaluate and indicate those varieties that were of
best performance in terms of quantitative and quantitative traits studied. Of
all the sixteen varieties of cowpea used in this work, IT97K-461-4,
IT99K-529-1, IT99K-429-2, IT99K-1122 and IT98K-506-1 were quite outstanding
and thus, these varieties were recommended for cultivation in this part of REFERENCES Dhagat, N.K. Goswami, U and Inghani, V.G. (1978) Genetic variability, character Correlation and path analysis in Barnyard Millet, Indian Journal of Agricultural Science 48(4): 211-214. Dulley, J. W and Mol, R. H (1969) Interpretation and uses of estimates of heritability and genetic variability in plant breeding. Crop science, 9:257-262 Elrod,s. L.a nd stanfield
W.D (2003) Genetics: Tata mcGram hill publication, Falconer, D. S. (1989) Introduction to Quantitative Genetic, 3rd
ed. Longman Science and technical. Faluyi, M. A. (1987) Investigation on the
relationship between yield and vegetative traits in cowpea in a tropical
rainforest environment. Hall, A. E. (2003) future directions of bean/cowpea Collaborative research program. Field crops Res. 82:233-239. Herry, R,J. (2004)
plant diversity and correlation: genotypic and phenotypic variations In
higher plant: edit by IITA (2002) Cowpea in sub-Sahara Africa: Ibadan, Nigeria. IITA. Johnson, H.W, Robinson, H. F. and Comstock, R. E. (1955) Genotypic correlation in Soyabean and their implication in selection. Agronomy Journal 47:477-485. Ogbuiya, P. O. 1997) Advances in cowpea Research. Biotechnology and Development Monitor 33:1012-1018. Wien, H. C. and Ackah, E. E. (1978). Pod development period in cowpeas: Varietal differences and related to seed characters and environmental effect, Crops science 78:791-794. |
TABLE 1. Mean and coefficient of variation
for the characters studied in the cowpea varieties.
Varieties |
NL |
NB |
PH |
SD |
PL |
PP |
PD |
SP |
1 |
27.0+ |
8.40 |
33.20 |
1.52 |
12.22 |
8.00 |
2.54 |
10.20 |
2 |
36.2 |
8.20 |
46.76 |
1.74 |
14.66 |
10.40 |
2.24 |
11.40 |
3 |
45.6 |
7.60 |
35.48 |
2.04 |
12.70 |
11.00 |
2.20 |
9.00 |
4 |
45.6 |
11.40 |
39.98 |
2.42 |
15.10 |
8.00 |
2.28 |
10.80 |
5 |
31.8 |
12.00 |
41.88 |
2.08 |
11.78 |
11.20 |
2.12 |
6.80+ |
6 |
31.8 |
7.20+ |
44.88 |
2.12 |
12.72 |
7.20 |
2.36 |
12.00 |
7 |
31.4 |
9.60 |
41.62 |
1.92 |
12.98 |
9.60 |
2.16 |
9.00 |
8 |
50.6 |
16.20 |
47.06 |
2.16 |
12.55 |
8.40 |
2.18 |
5.80 |
9 |
45.6 |
12.60 |
40.30 |
1.72 |
12.02 |
12.60 |
2.52 |
8.40 |
10 |
29.2 |
8.80 |
32.40 |
1.64 |
11.66 |
10.20 |
2.22 |
9.80 |
11 |
34.2 |
9.00 |
45.54 |
2.24 |
14.26 |
9.40 |
2.40 |
8.80 |
12 |
68.8 |
17.20 |
48.90 |
2.64 |
11.22 |
10.60 |
2.44 |
10.60 |
13 |
65.0 |
15.00 |
42.14 |
1.80 |
14.36 |
8.60 |
2.92 |
11.80 |
14 |
41.8 |
12.60 |
39.48 |
1.60 |
11.88 |
10.20 |
2.02 |
11.80 |
15 |
44.6 |
12.8 |
44.42 |
2.78 |
14.00 |
1.00 |
2.20 |
10.20 |
16 |
72.2 |
17.60 |
49.32 |
1.92 |
13.00 |
6.00 |
2.76 |
16.80 |
17 |
34.00 |
34.13 |
19.07 |
18.86 |
13.10 |
31.21 |
12.28 |
31.60 |
CV- means Coefficient of Variation NL - Number of Leaves Per Plant NB - Number of Branches Per Plant PH- Plant Height At Flowering SD - Stem Diameter PL - Pod Length PP - Number of Pod Per Plant PD - Pod Diameter SP - Number of Seeds Per Pod |
TABLE 2. Qualitative characters for the cowpea varieties.
S/No. |
Varieties |
Habit |
Seeds shape size and colour |
Flower colour |
Texture |
Leave shape and size |
1. |
IT99K-316-2 |
Erect |
Smooth, moderate and cream coloured |
White |
Smooth |
Trifoliate, moderate size shape |
2. |
IT97K-568-18 |
Semi-erect |
Smooth, moderate, and brown |
White |
Smooth |
Trifoliate, moderate, size ovate shaped |
3. |
IT96K610 |
Erect |
Smooth, moderate and white |
White |
Smooth |
Trifoliate, moderate, ovate |
4. |
IT98K-506-1 |
Semi-erect |
Smooth, moderate and white |
White |
Smooth |
Trifoliate, moderate, ovate |
5. |
IT98K-491-4 |
Erect |
Smooth, moderate and white |
White |
Smooth |
Trifoliate, moderate, ovate |
6. |
IT99K-491-7 |
Erect |
Smooth, moderate and white |
White |
Smooth |
Trifoliate small, ovate |
7. |
IT99K-1060 |
Erect |
Smooth, moderate and white |
White |
Smooth |
Trifoliate, large, ovate |
8. |
IT00K-898-5 |
Semi-erect |
Smooth big and white with brown patches around the eyes |
White |
Smooth |
Trifoliate, small, ovate |
9. |
IT97K-461-4 |
Erect |
Smooth, big and brown |
Purple |
Hairy |
Trifoliate, linear |
10. |
IT00K-1150 |
Semi-erect |
Smooth moderate, brown |
White |
Smooth |
Trifoliate, small |
11. |
IT98K-205-8 |
Erect |
Smooth, moderate, white |
White |
Smooth |
Trifoliate, small ovate |
12. |
IT99K429-2 |
Erect |
Smooth, moderate, white |
White |
Hairy |
Trifoliate, linear |
13. |
IT99K529-1 |
Semi-erect |
Wrinkled moderate and brown |
Purple |
Hairy |
Trifoliate, linear |
14. |
IT00K-901-5 |
Erect |
Smooth, moderate and white |
White |
Smooth |
Trifoliate, small, ovate |
15. |
IT98K-128-4 |
Erect |
Smooth, moderate and white |
White |
Smooth |
Trifoliate, large, ovate |
16. |
IT99K-1122 |
Profusely spreading |
Wrinkled, small and brown seeds |
Purple |
Hairy |
Trifoliate, large, ovate, leaves with purple veins, midribs and stems. |
TABLE 3. Correlation coefficient of characters in cowpea.
|
LEAVE |
BRANCH |
|
HEIGHT |
POD |
PODIAMET |
SEED |
PODLENGT |
LEAVE Pearson Correlation P. Value No of Observation |
1.000 80 |
.720 .000 80 |
285+ .010 80 |
367+ 001 80 |
.216 .054 80 |
.349+ .002 80 |
.261+ .019 80 |
.062 .584 .80 |
BRANCH Pearson Correlation P. Value No of Observation |
.720* .000 80 |
1.000 80 |
169 134 80 |
278+ .013 80 |
.065 .566 80 |
.207 .066 80 |
.125 .268 80 |
.189 .094 80 |
P. Value No of Observation |
.285 .010 80 |
.169 .134 80 |
1.000 80 |
325+ .003 80 |
.015 .895 80 |
.041 .590 80 |
.061 .590 80 |
167 139 80 |
HEIGHT Pearson Correlation P. Value No of Observation |
.367* .001 80 |
.065 566 80 |
325+ 003 80 |
1.000 80 |
.080 .482 80 |
.090 .429 80 |
.090 .429 80 |
.095 .403 80 |
POD Pearson Correlation P. Value No of Observation |
.216* .054 80 |
.005 566 80 |
.015 895 80 |
.080 482 80 |
1.000 80 |
.224+ .046 80 |
.224+ .046 80 |
.006 .957 .80 |
PODIAMET Pearson
Correlation P. Value No of Observation |
.349* .002 80 |
207 .096 80 |
.041 717 80 |
088 438 80 |
.210 .002 80 |
.300+ .007 80 |
.300+ .007 80 |
.085 .467 .80 |
SEED Pearson Correlation P. Value No of Observation |
.261 .019 80 |
125 268 80 |
.061 590 80 |
090 429 80 |
.224+ .046 80 |
1.000 .007 80 |
1.000 80 |
.151 .183 .80 |
PODLENGT Pearson
Correlation P. Value No of Observation |
.062 .584 80 |
189 268 80 |
167 139 80 |
095 403 80 |
.006 .957 80 |
.083 .462 80 |
.151 .183 80 |
.080 + 80 |
TABLE 4. Means and least significant difference (f-lsd at 5% probability) for vegetative characters in cowpea varieties.
S/N |
VARIETIES |
PLANT HEIGHT |
LEAF NUMBER |
|
BRANCH NUMBER |
1 |
IT99K-316.2 |
33.2 + 9.2609c |
27.0+5.3852e. * |
1.52 + 0.2588i |
8.4 + 3.1305fe |
2 |
IT97K-568.8 |
46.76 + 4.6226a |
36.2 + 7.1554cdc |
1.74 + 0.1517ilgf |
8.2 + 1.7889fe |
3 |
IT96K-610 |
35.48 + 8.152cb |
32.8 + 6.7602c |
2.04 + 0.1140fcdc |
7.6 + 1.1402f |
4 |
IT98K-506.1 |
39.98 + 3.6928ca |
48.6 + 2.8810b |
2.42 + 0.3962ba |
11.4+ 2.7012cdc |
5 |
IT98K-491.4 |
41.88 + 10.5554cba |
54.6 + 10.6911b |
2.08 + 0.134cdcb |
12.0 + 1.8708dcb |
6 |
IT99K-491.7 |
44.88 +5.5657ba |
31.8 + 7.7910c |
2.12 + 0.1483edcb |
7.2 + 1.7889f * |
7 |
IT99K-1060 |
41.62 + 6.1941cba |
31.45 + 4.3932c |
1.92 +0.2387hgfed |
9.6 + 1.402fcdc |
8 |
IT00K-898-5 |
47.06 + 5.9416a |
50.6 + 7.3007b |
2.16 + 6.1517dcb |
16.2 + 1.4832a |
9 |
IT97K-461-4 |
40.3 + 7.0512cba |
45.6 + 7.8294b |
1.72 + 0.1483ihg |
12.6 + 1.9494cb |
10 |
IT00K-1150 |
32.4 + 8.1403c |
29.2 + 5.2631c |
1.64 + 0.944ih |
8.8 + 0.8367fed |
11 |
IT98K-205-8 |
45.45 + 9.2479ba |
34.2 + 4.6583cd |
2.24 + 0.4336dcb |
9.0 + 2.000fcd |
12 |
IT99K-429-2 |
48.90+2.5348a |
68.8 + 5.8052a |
2.64 + 0.3782a + |
17.2 + 3.03329 |
13 |
IT99K-529-2 |
42.14 + 7.3238cba |
65.0 + 1.5811a |
1.80 + 0.1581ihgfe |
15.0 + 2.00ab |
14 |
IT00K-901-5 |
39.48 + 5.0796cba |
41.8 + 7.3959dcb |
1.60 + 0.2000ih |
12.6 + 4.6373cb |
15 |
IT98K-128-4 |
44.42 + 8.5596ba |
44.6 + 8.5332cb |
2.28 + 0.3347cb |
12.8 + 201679cb |
16 |
IT99K-1122 |
49.32 + 8.0272a + |
72.2 + 1.9235a + |
1.92 + 0.3670hgfed |
17.6 + 3.5777a |
|
FLSD |
9.35 |
8.66 |
3.24 |
4.65 |
TABLE 5. Means and least significant diference (f-lsd at 5% probability) for yield characters in cowpea varieties.
S/NO |
VARIETIES |
POD
NUMBER |
POD
LENGTH |
POD
DIAMETER |
SEED
|
1 |
IT99K-316.2 |
8.0
+ 0.7071 cb |
12.22
+ 1.3554d |
2.54
+ 0.1673 cb |
10.2+ 2.5884dcb |
2 |
IT97K-568.18 |
10.4
+ 1.8166ab |
14.66
+ 0.9099ba |
2.24
+ 0.2074 gfed |
11.4 + 2.4053cb |
3 |
IT96K-610 |
11.0
+ 3.1633 ab |
12.70
+ 1.4457 dcb |
2.20
+ 0.1225gfed |
9.0 + 2.3452cdc |
4 |
IT98K-506.1 |
8.0
+ 2.6458 cb |
15.10
+ 0.4301a + |
2.28
+ 0.2168gfed |
10.8 + 2.1678cb |
5 |
IT98K-491.4 |
11.
+ 4.7117 ab |
11.78
+ 1.8660d |
2.12
+ 0.1304gf |
6.8 + 0.8367cd |
6 |
IT99K-491.7 |
7.2
+ 2.5884 cb |
12.72
+ 0.9257 dcb |
2.36
+ 0.2881 gfdc |
12.8 + 1.9235b |
7 |
IT99K-1060 |
9.6
+ 1.9494 ab |
12.98
+ 1.1979 dcb |
2.16
+ 0.1817gfe |
9.0 + 2.3452cdc |
8 |
IT00K-898-5 |
8.4
+ 2.0736 cb |
12.50
+ 1.979dc |
2.18
+ 0.1643gfed |
5.8 + 0.8367c* |
9 |
IT97K-461-4 |
12.6
+ 3.3615 a + |
12.02
+ 1.0756d |
2.52
+ 0.1304 cb |
8.4 + 1.8166cdc |
10 |
IT00K-1150 |
10.2
+ 3.1145 ab |
11.66
+ 1.0455d |
2.22
+ 0.1643gfed |
9.8 + 1.7889dcb |
11 |
IT98K-205-8 |
9.4
+ 1.6733 ab |
14.26
+ 1.0455cba |
2.40
+ 0.1871edc |
8.8 + 2.1678cdc |
12 |
IT99K-429-2 |
10.6
+ 3.5777 ab |
11.22
+ 1.7641d |
2.44
+ 0.2966dc |
10.6 + 3.5071cb |
13 |
IT99K-529-2 |
8.6
+ 2.4083 ab |
14.36
+ 2.7574 cba |
2.92
+ 0.1095 a + |
11.8 + 2.3875cb |
14 |
IT00K-901-5 |
10.2
+ 1.9235 ab |
11.88
+ 1.3664 d |
2.02
+ 0.1095g * |
11.0 + 4.0620cb |
15 |
IT98K-126-4 |
11.0
+ 3.7417 ab |
14.50
+ 0.8367ba |
2.20
+ 0.1011gfed |
10.2 + 2.4900dcb |
16 |
IT99K-1122 |
6.0
+ 1.2247 c* |
13.00
+ 0.868.9dcb |
2.76
+ 0.2302bs |
16.8 + 1.3038a + |
|
FLSD |
3.68 |
1.81 |
2.492.49 |
3.14 |