EFFECTS OF TEMPERATURE, SEX, AND GENETIC BACKGROUND ON COLORATION OF CHORISTONEURA SPP. (LEPIDOPTERA: TORTRICIDAE) POPULATIONS IN SOUTH-CENTRAL OREGON

Abstract

AbstractColoration of larval, pupal, and adult progeny of Choristoneura spp. collected from Pseudotsuga menziesii (Mirb.) Franco and Abies concolor (Gord. & Glend.) Lindl. in south-central Oregon depended on the temperature at which the insects were reared. Sex and genetic background were also major sources of variation in coloration. Many of the characters which varied with temperature were thought to be of value in distinguishing C. occidentalis Freeman from C. retiniana (Walsingham). The association between a combination of larval characters and a combination of adult forewing maculations, though weak, allows a calculation of the probability that an adult belongs to a certain lineage defined by larval features. Individuals from mixed families were particularly difficult to categorize because of the variation encountered and the sensitivity of their appearance to rearing temperature. The biological significance of this variation and its implications to pest management are discussed.