2010 Annual Report
1a.Objectives (from AD-416)
1: Isolate and identify chemical factors responsible for host recognition and host acceptance by western corn rootworm larvae.
2: Evaluate the chemistry of alternate hosts and native sources of resistance in maize to WCR larval feeding for feeding stimulants and host-recognition factors and correlate their chemical profile with WCR behavior on these plants.
3: Evaluate potential applications of WCR larval feeding stimulants.
4: Evaluate feeding behavior of WCR larvae that are resistant to Cry3Bb1 transgenic corn on Bt and isoline corn.
1b.Approach (from AD-416)
A collaborative approach will be taken with Colorado State University (CSU). Aspects of the proposal having to do with chemical separations and identifications will be done at CSU along with most of the behavioral bioassays. Objective 4, all field work in Objectives 2 and 3, and insect rearing will be done by ARS in Columbia, MO. Aspects done at each location will be put together toward joint accomplishments.
To date, host recognition behavior has been evaluated for all currently-registered transgenic maize and targeted toward WCR and paired isoline maize without the Bt genes using susceptible WCR. No significant difference was found between Bt lines and their corresponding isoline maize lines in terms of total distance traveled, velocity, meander, or turn angle. All maize was significantly different than filter paper and oat controls. Bioassays for evaluating the role of feeding behavior of lines of the western corn rootworm with resistance to transgenic corn are under development.
Monitoring activities will include email exchange of information and results, telephone conference calls, and personal meetings at the Annual meeting of the Entomological Society of America.