Aliesterase Isozymes and Insecticide Susceptibility in Rice-Feeding and Water-Oat-Feeding Strains of the Rice Stem Borer, Chilo suppressalis WALKER (Lepidoptera: Pyralidae)

Genetic differences between rice and water-oat feeders in the rice stem borer, Chilo suppressalis (Walker) (Lepidoptera: Crambidae)

“…These results suggest that there could be population subdivision due to limited gene flow by differences in mating time between the two feeders; however, our allozyme analyses failed to detect unequivocal evidence of limited gene flow between the two feeders. This result also contradicts a previous study of the differences of aliesterase activities between the two feeders (Konno and Tanaka, 1996a). The study of Spodoptera frugiperda could be of help to understand this contradiction.…”

“…On the other hand, the few loci that diverged may be linked to loci in the regions of the genome associated with fitness and/or mate choice in each habitat (Prowell et al, 2004). In C. suppressalis, aliesterase activity, thought to be associated with detoxicate organophosphates, differed markedly between the two feeders (Konno and Tanaka, 1996a), because they have different histories of artificial selection pressure: an aliesterase variant with higher detoxication ability has spread in the population feeding on rice, whereas no such variant has spread in populations feeding on water-oats. These results and considerations suggest that the contradiction may be explained by the independence of our allozyme loci from the loci of detoxication.…”

“…These authors therefore concluded that there was no evidence of reproductive isolation between the two feeders. However, Konno and Tanaka (1996a) showed significant differences between the two feeders in insecticide susceptibility and activity of the aliesterase isozyme using moths collected in Okayama Prefecture. They also observed a clear difference in mating time between the two feeders under laboratory conditions: rice feeders mostly mated during the first half of the scotophase, while water-oat feeders mated during the late scotophase in moths from Okayama Prefecture (Konno and Tanaka, 1996b).…”

Polymorphic microsatellite loci for the rice stem borer, Chilo suppressalis (Walker) (Lepidoptera: Crambidae)

“…Konno and Tanaka (1996a) observed a clear difference in the mating time between the two feeders under laboratory conditions: most rice feeder mating was observed during the first half of the scotophase, while that of water-oat feeders was observed during the late scotophase. Konno and Tanaka (1996b) also showed significant differences between the two feeders in insecticide susceptibility and activity of the aliesterase isozyme. These findings suggest that the two feeders may essentially belong to different strains and could be reproductively isolated from each other.…”

Twelve nuclear microsatellite loci for rice stem borer (Chilo suppressalis W.)

“…Reports indicated that populations on rice and water‐oat have shown differentiation in behaviour and host preference (Takasaki et al . 1969; Konno & Tanaka 1996). On the other hand, although C .…”