Pw. Kidd et al., EFFECT OF CYHALOTHRIN ON FIELD POPULATIONS OF THE COTTON APHID, APHIS-GOSSYPII GLOVER, IN THE TEXAS HIGH-PLAINS, The Southwestern entomologist, 21(3), 1996, pp. 293-301
Cotton aphid, Aphis gossypii Clover, population densities in untreated
cotton plots were compared with those in plots receiving one and two
applications of cyhalothrin (Karate(R)) and one application of dicroto
phos (Bidrin(R)). The cyhalothrin applications were timed to simulate
typical treatment(s) for bollworm, Helicoverpa tea (Boddie), infestati
ons and the dicrotophos application targeted beneficial arthropods. Ra
pid increases in aphid population densities occurred within 2 wk of cy
halothrin applications, resulting in significant yield reductions. Aph
id numbers in dicrotophos treated plots were not significantly differe
nt from those in untreated plots on any sample date. Increases in aphi
d numbers did not appear to be due to reductions in predator populatio
ns, and predator populations appeared to increase only in response to
increasing aphid populations.