Implementing Biointensive IPM Systems in Cling Peaches

Abstract

A complete mating disruption program that uses pheromone confusion technology successfully controlled oriental fruit moth and peach twig borer while eliminating most in season insecticides in cling peaches from 1995–1997 in a three-county area. During this 3-year period, 46 cooperators used this program on 580 acres. Growers applied both Oriental fruit moth and peach twig borer pheromone dispensers twice. Orchards were monitored for moths and for shoot strikes during the season. Harvest samples were taken to determine worm damage. A few orchards were sprayed once when shoot strike counts exceeded threshold levels of three to five strikes per tree. Along with mating disruption in 1997, 209 acres were sprayed with Bacillus thuringiensis during bloom to replace the dormant insecticide spray and improve efficacy of pheromone confusion. Throughout implementation, mating disruption program costs were compared with conventional spray programs. Between 1995 and 1997, the complete mating disruption program cost decreased from $243 per acre to $216 per acre respectively. Even with the decrease in cost, this is much higher than $104 per acre for the standard spray program. Some growers decreased pheromone dispenser applications in 1997 for a more economic program. This program still reduced pesticide use by 33% to 67%. While most growers using this partial program had success, some orchards had high shoot strikes indicating a potential problem. Grants from USDA-ES-Smith-Lever IPM project, EPA Environmental Stewardship Partnership, California Department of Pesticide Regulation and Farm Service Agency cost share programs aided in our ability to implement these biointensive programs; they provided the money necessary for monitoring and reducing direct costs to the grower. The main obstacle to cling peach growers adopting the complete biointensive program is the economics. Most growers will continue to spray or use a partial mating disruption program until less expensive commercial products become available.