2010 Annual Report
1a.Objectives (from AD-416)
The goal is to maximize the effect of physical, chemical, and biological stressors to control stored-product insects in raw grains and processed grain products. Stored-product insect pests reduce the quality of stored grain and grain-related products in the U.S. and in the world. We will identify new methods of controlling insect pests in stored products, targeting controls to specific sites or areas, and determining how insect immune systems can be exploited to improve efficacy of new control strategies. We will identify and refine alternative insecticides, biologically-based control methods, and physical controls to manage stored-product insect pests. We will evaluate selective targeted controls and application strategies to manage insect pests in different stored-product systems.
1b.Approach (from AD-416)
Laboratory and field experiments will identify new biologically-based methods and reduced-risk insecticides to control stored-product insect pests, evaluate synergistic and additive effects from selected control agents, and to further refine physical controls, such as heat and aeration, to modify storage environments. Laboratory and field tests will investigate targeted applications of control agents, detect pathogen virulence in field populations of stored-product insects, and examine new methods for using pathogenic controls to regulate pest populations in stored products. Our research will also include detailed analysis of the cuticular lipids in the insect cuticle, and analysis of how these properties affect their response to various control agents. We will investigate how insect immune responses are regulated and how physiological responses can be interrupted and manipulated to enhance efficacy of control agents. Our research will provide new methods to control insects in raw grains and processed grain products, strategies for integrating different control agents, information on using targeted controls for specific areas within stored-product facilities, and knowledge of how the insect immune system could be exploited to improve control from reduced-risk insecticides and insect pathogens. Results will provide practical information for minimizing risk, quality deterioration, and economic damage caused by stored-product insects.
This is a bridging project for project 5430-43000-025-00D that was terminated this year. A new 5-year project is currently in peer review and will be implemented in FY 2011. Laboratory colonies of hide beetles have been established from a field population and procedures to mass-rear beetles are being developed. Preliminary tests are being conducted to determine susceptibility to entomopathic fungi and contact insecticides. Commercial fungal preparations have been evaluated for efficacy and some appear to be effective controls. Initial results from experiments with contact insecticides seem to indicate that the hide beetle is more difficult to kill compared to red flour beetles and confused flour beetles. Aeration as a pest management strategy for stored rough rice was evaluated though a web-based management program. The program utilized insect population models integrated with bin-cooling models to predict insect pest population growth in aerated and unaerated rice.
Aeration model developed for stored rice. The practice of cooling stored rice through aeration is an under-utilized strategy for insect control. Predictive models can show how aeration could greatly reduce insect populations. In cooperation with scientists at Texas A&M University, ARS scientists in Manhattan, KS, developed a web-based rice management system that includes a model that predicts lesser grain borer and rice weevil population growth in unaerated and aerated rice. Simulations for Beaumont, TX, which is located in a region where rice can be harvested and stored in August, show that aeration dramatically reduces the populations of insects through cooling of the stored rice. Results show the utility of the web-based model and how the various model inputs can help define broader patterns of insect control in rice stored in the south-central United States.
Fungi kill hide beetles. Hide beetles are emerging pests of stored products for which biological controls are untested. ARS scientists in Manhattan, KS, have three fungal species that are commercially produced for insect control to assess their efficacy for hide beetle larvae on 5 substrates. Of the three fungi, Beauveria bassiana was the most efficacious. Among the substrates, only wood had an effect on insect mortality, but the fungal conidia died rapidly on both wood and leather. Results indicate these entomopathic fungi can be used to control hide beetles.