Quantitative variation in adult size and fecundity of the cotton stainer bug dysdercus fasciatus

Abstract

Genetic variation in adult size and fecundity was studied in the cotton stainer bug Dysdercus fasciatus in the laboratory using a split-family, two-environment, half-sib, full-sib design. Groups of siblings were grown in either a benign or a stressful moisture environment. Sib analysis in each environment revealed additive genetic variance for adult size and fecundity only in the benign environment. Heritability estimates were zero for adult size and low for fecundity when averaged over the two environments. A substantial component of the phenotypic variance in adult size and fecundity was due to genotype-by-environment interaction. This result indicates that different genotypes would be favoured in different conditions if the selection occurred in a heterogeneous moisture environment. © 1991 The Genetical Society of Great Britain.