Release of transgenic white clover plants expressing Bacillus thuringiensis genes: An ecological perspective

The destructive effects of indigenous insects on pasture plants are a significant cause of diminished pastoral productivity in New Zealand. Identification of white clover genotypes with natural immunity against native insects has not been successful, so farmers use chemical sprays to control pest populations. An alternative strategy to reduce insect damage to white clover is through development of a transformation system using Agrobacterium‐mediated transfer DNA. We have developed a rapid procedure, where transgenic white clover plants regenerate directly from the cotyledonary axil of germinated seedlings and can be transferred into the glasshouse within 42 days of culture initiation. This technology offers the opportunity to improve the sustainability of white clover in New Zealand pastures by introducing pest resistance genes directly into these plants. Insect feeding bioassays have identified several serotypes of Bacillus thuringiensis (Bt) with δ‐endotoxins active against larvae of the lepidopteran pe...