Project Number: 6204-22000-019-00
Project Type: Appropriated

Start Date: Oct 01, 2005
End Date: Aug 31, 2010

Objective:
Biological control strategies will be evaluated for management of emerging cotton pests and the exotic weed, Arundo donax. The lethal and sub-lethal effects of pesticides on key natural enemies of glassy-winged sharpshooter will be investigated to support IPM programs for this pest. Specific objectives are: 1) Identify, collect, culture, and evaluate candidate natural enemies for efficacy against lepidopteran pests, including the beet armyworm and the cotton bollworm, as well as the green cotton mirid; 2) Evaluate the effects of pesticides on selected natural enemies of glassywinged sharpshooter and selected predaceous spiders in the cotton agroecosystem; 3) Evaluate the potential of entomopathogens to manage the varroa mitre and glassywinged sharpshooter; and 4) Determine the distribution and origin of Arundo donax, giant reed, in the Rio Grande River Basin, and assess the potential impact of candidate biological control agents to manage this invasive weed of riparian habitats.

Approach:
The BIRU will discover and evaluate beneficial insects and pathogens for biological control of the most serious pests and weeds of agriculture in the southwestern U.S., with applications of this research at the national and international level. Changes in cotton production in this region due to the potential eradication of the boll weevil and adoption of transgenic Bt cotton varieties has reduced use of broad spectrum insecticides to control key pests. This pest management strategy has resulted in the emergence of formerly secondary insects such plant bugs as serious pests. New management strategies must be developed to reduce the pesticide use in cotton. The biology and ecology of these emergent pests will be investigated, with the goal of learning where they originate before entering crops, identifying their natural enemies, devising methods to manipulate or otherwise conserve them, and to import new natural enemies for classical biological control. Further, the role of nocturnal spiders will be investigated to quantify the important role they play as predators of Lepidoptera eggs (beet armyworm & bollworm) and to support their conservation in the agroecoystem. The effects of pesticides on key natural enemies, including those of the green cotton mirid and glassy-winged sharpshooter, will be measured, and least toxic insecticides will be identified. This will allow producers to reduce their pest problems while protecting natural enemies. The insect pathology program will concentrate on technology transfer of a pathogen treated hive strip for control of varroa mite with honey bees. Water resources are critical to agriculturists, land managers, and urban users in the arid southwestern U.S. A biological control program to manage giant reed, an exotic water-using weed in the Rio Grande Basin, will be initiated.