PRELIMINARY EXAMINATION OF THE EFFECTS OF LORSBAN APPLICATIONS FOR PINK BOLLWORMCONTROL ON BENEFICIAL AND SECONDARY PEST POPULATIONS

摘要

The effects of Lorsban 4E applications for pink bollworm control were assessed for populations of beneficial arthropods andsecondary pests on Acala cotton in New Mexico. Treatments consisted of early-, mid-, late-season, and season-longapplications of lorsban applied at 10-day intervals. Populations of beneficials and plant bugs were estimated with a suctionsampler, aphids with leaf counts, and pink bollworm with examination of bolls. Aphid populations were very low this seasonpeaking at an average of slightly over 4 per leaf. Late-season pink bollworm infestations reached as high as 56.3% in thelate season treatment. Lorsban applications did not appear to affect the seasonal abundance of the majority of predaceousHeteroptera, lacewings, or plant bugs. Only populations of Geocoris and spiders were significantly less than the control.Lady beetle numbers were significantly lower numbers in the 1AP and 2 AP treatments. This is likely credited to low aphidpopulations that did not begin to build until just prior to the beginning of the 3AP treatment. Based on one year's research,results indicate that repeated use of Lorsban 4E in southern New Mexico during a light aphid year should not result in anincrease of cotton aphids above that of an untreated field. Possible reasons for these results are briefly discussed.