2009 Annual Report
1a.Objectives (from AD-416)
To accelerate and enhance the formulation of high performance insect diets that improve the fitness of mass reared insects used in research and insects used in the biological control of insect and weed pests by: .
1)improving the formulation of artificial diets and diet-delivery systems;.
2)determining the impact of nutrient substitutions on the efficiency of diet utilization; and.
3)developing genomic biomarkers to monitor fitness traits related to nutrition.
1b.Approach (from AD-416)
Formulation changes will be made to micronutrient levels and substitutions will be made for the fibrous, temperature sensitive and antibiotic materials in artificial diets as part of an empirical-based effort to improve artificial diets. Life history measurements will be used to assess the impact those dietary changes on the health of the insect. The impact of dietary component changes on the biochemical fate of nutrients will be monitored. Enzymatic activity and metabolism of nutrients will be used to assess the impact of dietary changes on the efficiency of nutrient absorbance and nutrient utilization. The use of genomic biomarkers as indicators of fitness for insects reared on diets varying in nutritional quality will be investigated. Differentially-expressed genes will be identified using suppressive subtractive hybridization and microarray analyses.
We manipulated insect diets to investigate the involvement of the food stream on digestion, gene expression and insect performance. Beneficial and pest insects were reared on modified diets and tested for digestive rate changes, secreted and internal protein expression, growth and cold storage performance. Additionally, a diet formulated for predatory insects was tested for rearing a newly emerging pest insect.
We enhanced our determination of prey half-life within the digestive tract of predators and consequently improved the ranking of predators in controlling prey populations. This research on the digestive rates and genetic determinants of agriculturally important insects is helpful in uncovering prey preferences and consumption rates which will improve the use of beneficial insects in biological control programs.
Our comparison of secretory processes and proteins among sharpshooters, a group of pest insects, demonstrated that the form of liquid saliva and saliva protein content contributed to the sharpshooters’ ability to transmit plant diseases. This new information on the biology and behavior of a pest insect is critical to improving and developing new and innovative control strategies for this insect and other insects that feed in a similar manner and consequently directly threaten agricultural crops.
Our discovery that nutrient changes to the diet of the fruit fly modulated specific gene expression associated with increased energy production improved our ability to formulate diets for rearing the fruit fly and other insect species. Subsequently, we are developing new rearing methods for the mass production of insects that will improve our management of insect pests through integrated pest management practices for the eradication of the fruit fly as a pest.
We evaluated the influence of nutrient source on the response of a beneficial predator to short and extended storage at cold temperatures and demonstrated that performance after cold storage can be modulated by adjusting the diet prior to the storage period. This improved our ability to measure the effect of biotic and abiotic factors that impact the performance of biological control agents and we have developed new and improved biological and cultural methods for the use of mass reared beneficial insects.
Diet Enhancement of Storage of Predatory Insects. Conceptual and practical advances in biological control programs requires more efficient and effective methods to store insects for short and extended periods to reduce the costs of rearing and transporting insects. Cold insect storage is a common practice, however, the insect response and performance quality are not well understood. Our study demonstrated that eggs, immatures and adults of the beneficial predatory two spotted stink bug respond differently to short and extended periods of storage at cold temperatures. Also nutrition affected the ability of each developmental stage to tolerate cold storage. In particular, for extended cold storage it was more advantageous to rear insects on natural prey and to hold insects at 10 deg C than at 4 deg C. In contrast, for short periods neither the temperature nor the food source affected the response to cold storage, with the exception that diet-fed immatures survived better than prey-fed immatures. Commercial producers and researchers will find this information useful when developing storage regimes and food sources that minimize their operational costs and maximize the fitness of their insects for sale and release purposes or when storing a colony between uses.
5.Significant Activities that Support Special Target Populations
Scientists on this project have mentored an undergraduate student scholar from an 1890 institution who was sponsored by MWA and BCIRL to participate in the University of Missouri undergraduate research scholars program. The research conducted by the scholar supported the research project objectives.
|Number of the New/Active MTAs (providing only)||1|
Coudron, T.A., Popham, H.J., Ellersieck, M.R. 2009. Influence of Diet on Cold Storage of the Predator Perillus bioculatus (F.). Biocontrol 54:773-783.
An, S., Wang, S., Stanley, D.W., Song, Q. 2009. Identification of a Novel Bursicon-regulated Transcriptional Regulator, md133790, in House Fly Musca domestica. Archives of Insect Biochemistry and Physiology. 70:106-121.
Li, X., Niu, C., Huang, Q., Lei, C., Stanley, D.W. 2009. Life Cycle of Chetoneura shennonggongensis (Diptera: Keroplatidae, Keroplatinae) From Jiangxi Province, China. Insect Science. 16:351-359.
Wang, S., An, S., Stanley, D.W., Song, Q. 2009. Cloning and Characterization of a Bursicon-Regulated Gene Su(H) in the House Fly Musca domestica. Insect Science. 16:207-217.