February 4, 2015
Dr. Ralf Nauen, Bayer CropScience
Dr. Nauen is a Bayer CropScience Research Fellow working in Monheim, Germany. He is is the recipient of the 2014 ACS International Award for Research in Agrochemicals. He is internationally recognized for his research in insect toxicology and resistance, which has focused on insecticide mode of action and insecticide and acaricide resistance mechanisms and management.
Oilseed rape (Brassica napus) is a crop of global economic importance. Particularly in Europe, winter oilseed rape cultivation exploded in the 1990s, and it is now grown on several million hectares representing 30% of the worldwide production. Along with the expansion of winter oilseed rape acreage in Europe, coleopteran pests also became more widespread, leading to an annual invasion of this crop by billions of beetles of the genus Meligethes (pollen beetle). Over the years this European mega pest developed widespread, high metabolic P450-driven resistance to a major chemical class of insecticides, the pyrethroids. Although new modes of action have been introduced for Meligethes control, selection pressure by pyrethroids remains high for various reasons. The paper reviews ten years of research on molecules, monitoring, mechanisms and management conducted to investigate a remarkable case of resistance evolution that has spread throughout an entire continent. From both fundamental and applied aspects it is an exciting case study exemplifying both failure and success in insecticide resistance management in modern applied entomology.