Herbicide resistant crops: History, development and current technologies

Advances in biotechnology have led to development and commercialization of several herbicide-resistant crops (HRCs) in the mid-1990s. HRCs survive herbicide treatment that previously would have killed the crop along with targetted weeds. Both transgenic (created through stable integration of a foreign gene) and non-transgenic (developed through traditional plant breeding) HRCs are commercially available to farmers. Although several HRCs are available, only transgenic HRCs, such as, glyphosateand glufosinate-resistant crops appear to have greatest impact and dominate the market. HRCs are readily accepted in North and South America and are slowly making inroads into other parts of world. Farmers who have chosen HRCs must have seen some economic and weed control benefits; otherwise, the rapid increase in area planted to HRCs in recent years would not have occurred. There are benefits and risks associated with the use of HRCs as a weed management tool. The benefits of HRCs for weed management outweigh the risks based on current knowledge. HRCs should not be relied on solely to the exclusion of other weed control measures and should be used within integrated weed management programmes.