Weed control of crops constitutes a major factor in determining agricultural yields. Over the past fifteen years, in parallel with research into new selective herbicide molecules, a complementary approach has been developed: the selection of crop plant varieties tolerant to existing herbicidal substances. These varieties, known as herbicide-tolerant varieties (HTVs), offer farmers a technical response to the challenges of weed control. Their use is presented as permitting a reduction in the quantities of herbicides used. What are the medium and long-term effects of the cultivation of HTVs? What role can they play in policies aimed at reducing pesticide use?
The conclusions of this collective scientific expert report conducted jointly by CNRS and INRA at the request of the French Ministries of Agriculture and Ecology were made public on November 16, 2011. One of the results shows that the repeated use of HTVs, under certain conditions, may render them ineffective in the medium term. This expert report also highlights the need for weed management based not only on these new varieties, but also integrating different complementary methods.