ISSN 2375-1231
African Journal of Crop Science ISSN 2375-1231 Vol. 6 (7), pp. 001-006, July, 2018. © International Scholars Journals
Full Length Research Paper
Genetic variability, stability and relationship among some Cowpea, Vigna unguiculata (L.) Walp breeding lines
Adeigbe, O. O.1,2* Adewale, B. D.1 and Fawole, I. O.2
1Crop Improvement Division, Cocoa Research Institute of Nigeria, Ibadan, Nigeria.
2Department of Crop Protections and Environmental Biology, University of Ibadan, Ibadan, Nigeria.
Accepted 07 April, 2018
Abstract
The contribution of cowpea to food security in the sub-Sahara Africa is incontestably obvious. Ten genotypes of cowpea were evaluated in different environments to assess their variability and stability. The genotypes differed significantly (P≤0.05) with respect to all the eight phenotypic traits studied. Days from planting to first flower production and to first ripe pod showed the least coefficient of variations (CV) in all environments. The number of branches per plant consistently had the highest genotypic and phenotypic CV in all the three environments. The mean proportion of the phenotypic variation due to genetics was 92.9%. The ten genotypes varied considerably in their stability for the studied morphometric traits. The most stable genotype for days to first flowering (DFF) and days to first pod ripening (DPRP) was IBS9193. However, 25026-2 and 24893-2 were most stable for pod length (PL) and peduncle length (PDL), respectively. Significant genetic and phenotypic correlation existed among the variables; implying typical association among the tested traits. For example, the number of pods per plant negatively but significantly (P≤0.01) correlated with DFF and DPRP. This study indicated that a meaningful selection of genotypes is possible for multi-trait improvement through hybridization.
Key words: Heritability, stability, selection, variances, correlation coefficients.