Tuesday, December 12, 2006

Identification of volatiles involved in host plant location by female grape berry moth

Dong Ho Cha, dhc28@cornell.edu, Stephen P. Hesler, sph12@cornell.edu, Satoshi Nojima, toshi_nojima@ncsu.edu, Shannon B. Olsson, shannonolsson@ucla.edu, Charles E. Linn, cel1@cornell.edu, Wendell L. Roelofs, wlr1@cornell.edu, and Gregory English-Loeb, gme1@cornell.edu. Cornell University, Department of Entomology, New York State Agricultural Experimental Station, 630 W. North St, Geneva, NY

Grape berry moth (Endopiza viteana) is a key, direct pest of grapes in the Northeastern USA. Although pheromone traps are available to monitor the two to four within season male population peaks, there is often poor correspondence between trap catches of males and egg laying activities of females, even more so toward later season when grape berry moth (GBM) pressure is high. In flight tunnel assays, shoots from wild and cultivated grapes were most attractive to both mated and unmated females, but other tissue types including flowers, berries and even apple shoots also induced some female GBM attraction. We analyzed head space volatiles of grape shoots using Solid Phase Microextraction and GC-EAD and identified a mixture that shows high levels of behavioral activity. One hurdle in the use of host volatiles as a lure to capture GBM in the field, however, is ubiquitous nature of plant volatiles. In other words, the signal from the lure is potentially lost in the background “volatile noise” produced by the host plants within the vineyard. One way to overcome this problem is to include some unique volatiles in the lure that are attractive but not present during the time or in the location the lure is being deployed. With this in mind, we report on recent research results searching for unique volatiles from grape flowers, apples, and distantly related wild grape Vitis rotundafolia that are attractive to female GBM but not present during the summer season of Northeastern US vineyards.

Species 1: Lepidoptera Tortricidae Endopiza viteana (grape berry moth)