Genetic studies using the orange body color type of Nezara viridula (Hemiptera: Pentatomidae): Inheritance, sperm precedence, and disassortative mating

Abstract

Nezara viridula (L.) (Hemiptera: Pentatomidae), the southern green stink bug, has body color polymorphisms. N. viridula f. smaragdula is the common green morph, whereas the rare morph N. viridula f. aurantiaca is uniformly orange. Crossing studies were conducted to determine the inheritance of the orange body color trait. Mendelian genetic analysis suggested that orange body color is a simple, sex-linked recessive trait. In sperm precedence studies using orange females crossed with green and then orange males, or vice versa, the proportion of offspring attributable to the second male, P2, averaged 73.39% (extremes 23.5-100%). The average P2 in the first egg mass deposited after the new pairing was 71.8%. The pattern of sperm use provided evidence for incomplete sperm mixing, sperm stratification, and sperm displacement. Green females preferred mating with orange males (88%) compared with green males (12%), suggesting that disassortative mating may operate.