Wednesday, December 13, 2006 - 8:05 AM
1068

Effect of soil type and moisture on adult eclosion of Swede midge (Contarinia nasturtii)

Mao Chen, mc447@cornell.edu1, Anthony Shelton, ams5@cornell.edu2, and Jianzhou Zhao1. (1) Cornell University, Entomology, 630 W. North Street, Geneva, NY, (2) Cornell University, Department of Entomology, P.O.Box 462, 630 W. North St, Geneva, NY

Swede midge (Contarinia nasturtii Keiffer) is a serious gall-forming insect pest of cruciferous plants in Europe and southwestern Asia. In North America, it was first identified in Ontario, Canada, in 2000 and in Niagara County, New York, the United States, in 2004. The insect is now rapidly spreading both in Canada and the US. To date, infestation of C. nasturtii has been confirmed in 40 counties in Canada and 6 counties in the US. Pheromone trap captures indicated that the occurring level of C. nasturtii varied in different counties. 5 different types of soil were collected from 5 different sites in NY State in order to assess the impact of soil type and moisture on adult eclosion of C. nasturtii. Results indicated C. nasturtii adults could not emerge from most of the saturated and absolutely dried soil. 50 % and 75 % relative moisture conditions of most of the soil were good for adult eclosion. In laboratory conditions, most of C. nasturtii larvae pupated within the depth of 1 cm in all different soil. 2, 5 and 10 cm deep soil was added to the top after C. nasturtii larvae jumped into the soil in order to evaluate whether cultivation depth could impact adult eclosion of C. nasturtii. Percentages of adult emergences were significantly reduced when depth of soil cover increased. There was no consistently significant difference between soil types.


Species 1: Diptera cecidomyiidae contarinia nasturtii (swede midge)