Adoption of recently introduced herbicide tolerant soybean varieties has been extremely rapid. By 1998, approximately 38% of the total US soybean acreage was planted to varieties developed through the use of biotechnology methods to be tolerant to various herbicides. The first herbicide tolerant varieties, sulfonylurea tolerant soybeans, were introduced in 1993 and were developed to tolerate higher rates

Take-all decline (TAD) is a natural biological control of the wheat root disease “take-all” that develops in response to the disease during extended monoculture of wheat. The research to date on TAD has been mostly descriptive and no particular occurrence is yet fully understood.