Inheritance and combining ability estimates for cowpea resistance to bruchid (Callosobruchus maculatus Fab.) in Benin cowpea

Abstract Cowpea bruchid (Callosobruchus maculatus Fab.) is the most important storage pest causing significant economic losses. Development of bruchid resistant cowpea varieties is the most sustainable strategy for controlling bruchid. However, information regarding the nature of gene action governing the resistance to bruchid is limited for cowpea genotypes in Benin. This study aimed to understand the genetic basis of cowpea resistance to C. maculatus. Eight parents were crossed in a full diallel mating design. 56 F2 progenies were tested with the eight parental genotypes in alpha lattice design with three replications in laboratory. Data were recorded on bruchid emergence (BE); weight loss (WL); median development period (MDP); Dobie susceptibility index (DSI); number of eggs laid (NEL); average number of holes (ANH); seed damage (SD). Combining ability analysis was performed using Griffin's method 1, model 1 in AGD-R software. The results showed that general combining ability (GCA) effects were highly significant (p