Response to selection for grain yield and correlated response for grain size and earliness in cowpea based on early generation testing

Abstract

Large grain size and earliness to flowering are traits critical to cowpea adoption in the West African savannahs. This study reports on the correlated response to selection in these two traits in the two populations in which selections were made primarily for grain yield potential. Further, the present study reports on the effectiveness of early generation selection for grain yield. Each of the two populations, SARC 2 and SARC 3, was derived from a cross between an adapted parent Marfo-Tuya and an exotic breeding line that has large grain size and early flowering. Replicated yield evaluation of F 5 families showed that grain yield of Marfo-Tuya was not different from those of the highest yielding families in each population. Increases in grain size of individual families over Marfo-Tuya were large and, the response to selection averaged 5.3 and 3.9 g/100 seeds in the SARC 2 and SARC 3 populations, respectively. Response to selection in days to flowering averaged 3 days in SARC 3, whereas response to selection was not observed in SARC 2. Retrospective selection in the F 3 at 40% intensity was efficient in identifying a high proportion of elite families in each population.

Evaluation of Planting Dates on Growth and Yield of Three Cowpea [Vigna unguiculata (L) Walp.] Genotypes in Northern Ghana

“…It was able to recover quickly from drought during the growing season and produce higher yields. This corroborates many drought study by [23,24] Padi-tuya produce higher yield in the first, third and fourth planting date, and had the second highest yield in the second planting date. The genotype T 2 T 4 also gave appreciable yield in the second planting date, and produces the second highest yield in the first second and third planting dates.…”

Genetic Analysis of Vegetative-Stage Drought Tolerance in Cowpea

“…The low estimate of heritability for days to flowering based on parent-hybrid regression is not surprising. The dominance of earliness to flower over lateness to flower in cowpea is well known but with few genes underlying this trait selection should be effective in the early generations (Padi, 2008). Among these traits, the hundred seed weight (a measure of grain size) is the most important to consumers, directly influencing the market value of cowpea grains in West Africa ((Langyintuo et al, 2003).…”

“…The haulms are used as fodder for livestock particularly during the dry season (Blade et al, 1997). Although cowpea contributes significantly to the income of farmers in the northern savannah zones of West Africa where varieties with grain yield potentials in excess of 3.0 t/ha have been developed for cultivation, farm level yields of cowpea are within the range of 0.3 to 0.65 t/ha (SARI, 1996 and1997).…”

Diallel analysis in cowpea aiming at selection for extra-earliness

“…Adeyanju and Ishiyaku (2007) reported that earliness is an important agronomic trait, and it is important for cowpea in areas with relatively short rainfall cycle. Padi (2007) mentions that grain size and earliness are essential traits for the adoption of cowpea cultivars in the savannas of West Africa.…”