INTERACTIONS OF WEEDS WITH SELECTED ARTHROPOD GROUPS AND COTTON IN THE LOWER RIO GRANDE VALLEY OF TEXAS

摘要

Vegetative diversification of agroecosystems with weeds has shown promise as a technique for enhancing natural enemy populations and suppressing pest induced damage to various crops. This study, using weedy (W) and weed-free (WF) cotton plots in theLower Rio Grande Valley of Texas in 2000, showed that although some groups of herbivorous arthropod groups supported higher populations of some soil- and foliage-associated natural enemies, boll weevil damage to squares was not reduced. It is conjecturedthat this was because natural enemy populations were highest in late May and June, after most squares had become bolls and were less vulnerable to boll weevil oviposition than squares, and because the predators encountered are not effective enemies of boll weevils. Numbers of cotton bolls and lint yields were lower in W habitats than in WF habitats because of competition with the weeds.