Evoluzione e gestione della resistenza ai graminicidi in Lolium spp

Enquiries about poor control of Lolium spp. by clodinafop and tralkoxydim were monitored for six years. The 112 seed samples collected from durum wheat fields in 69 farms in central and southern Italy were tested in a greenhouse with three ACCase inhibitors and one sulfonylurea. 60% of the populations proved to be resistant to one or more ACCase inhibitor herbicides and 50% of these showed cross-resistance. In 2002-2004, 27% of populations were also inadequately controlled by the sulfonylurea. Six years of field experiments testing the efficacy of chemical and agronomic means for controlling resistant Lolium spp. are presented. No single chemical or agronomic treatment solved the problem of resistant populations. False seedbed preparation and some alternative herbicides proved useful. Integrated weed management appears to be the best solution.