Associations of allozyme variation and behavior in the cowpea weevil (Callosobruchus maculatus)

The cowpea weevil (Callosobruchus maculatus (Fabré)) exhibits several behavioral traits that are stable within, but vary among, strains. These traits are heritable and quantitative. We used cellulose acetate gel electrophoresis to quantify allozyme variation within and among laboratory cultures of four weevil strains and determine whether allozyme variation correlates with behavioral traits. Significant variation exists at 8 of 11 loci assayed and gene frequencies are significantly different among strains. The South Indian strain (SI) is most variable and measures of genetic distance set it apart from the other strains. It is also behaviorally unique. The Brazilian strain (BC) is most different from SI in allozyme diversity and behavioral phenotype, while two African strains (IITA, CAM) are intermediate in allozyme diversity and phenotype. These results are consistent with the known history of these strains and the differences in the allozymes parallel the differences in behavioral traits.