Development of Bt Collard as a Trap Crop for Cabbage 2002
Elizabeth Earle (Dept. of Plant Breeding, Ithaca)
Mark Farnham (USDA-ARS-U.S. Vegetable Laboratory, Charleston, SC)
Brian Nault (Dept. of Entomology, Geneva AES)
Anu Rangarajan (Dept. of Horticulture, Ithaca)
Tony Shelton (Dept. of Entomology, Geneva AES)
Type of Grant:
Wherever cabbage is grown. The general principle being tested (GM-trap crops) is relevant nationally.
This work seeks to protect crops from insect pests by combining approaches from biological control and biotechnology. More specifically, it aims to protect cabbage from diamondback moths (DBM) through use of a collard trap crop expressing insect-resistance genes from Bacillus thuringiensis (Bt). DBM lay more eggs on collard plants than on cabbage but the larvae that hatch from these eggs survive. Bt-transgenic collard plants would attract DBM egg-laying and would also kill the hatched larvae, providing more effective insect control in a mixed field of cabbage and collard. During this grant period, we introduced two different Bt genes into collard varieties "Champion" and "McCormacks Green Glaze" and confirmed that DBM larvae die on leaves of these plants. Plants with high production of the insecticidal Bt protein were identified. Some of these plants have been self-pollinated or crossed with cytoplasmic male sterile (CMS) cabbage. The crosses with cabbage are a first step toward production of CMS Bt-collard, which would eliminate any problems of transgenic pollen flow. Seeds are being recovered from the crosses. These seeds and other Bt- collard plants available will soon be used in comparisons of DBM egg-laying and insect damage on standard collard and cabbage. Field tests of various ways to deploy the Bt-trap crop and cabbage are planned for next summer.