Location: Plant Genetics Research
Project Number: 5070-21000-038-12-T
Project Type: Trust Fund Cooperative Agreement
Start Date: Mar 15, 2013
End Date: Sep 14, 2017
1) Develop an improved, standardized artificial diet for western corn rootworm larvae that can be used in diet-toxicity assays with all toxins targeted for transgenic rootworm control, 2) Compare differing plant-based assays for cost efficiency and their ability to detect resistance to transgenic toxins targeting rootworms, and 3) Develop an efficient artificial diet system capable of rearing western corn rootworm larvae all of the way to beetle emergence.
For Objective 1, we intend visit facilities currently doing work with western corn rootworm artificial diets to learn aspects of this work that are more art than science. We have been told that our industry colleagues are likely to contribute proprietary progress beyond the published diet so that a standard diet can be used for all proteins. We first will compare rearing success to all diets prior to systematically modifying aspects of the diet to include feeding stimulants and host recognition cues. Finally, when we have optimized the diet for rearing larvae 7 days, we will begin testing resistant colonies to each protein. Objective two will consist of a thorough comparison of each plant-based assay. We will evaluate each resistant colony in each assay to see which is most efficient in detecting resistance to each protein. It is possible that results will vary with protein and resistance source, but we will attempt to first optimize for detection of resistance and then optimize for economic efficiency. Finally, we will work toward additional modifications to the diet to which we can rear western corn rootworm larvae all of the way to pupation. In doing this, we will evaluate microbes and antibiotics and fungicides currently used in the diet along with our Wolbachia-free western corn rootworm colony to see if an understanding of rootworm microbe interactions will facilitate rearing all of the way.