Occurrence and Mechanism of Papaver rhoeas ALS Inhibitors Resistance in Poland

Herbicide resistance in weeds, including corn poppy (Papaver rhoeas L.), is an increasing problem compromising global crop production. The aims of this study were to evaluate the susceptibility P. populations Poland acetolactate synthase (ALS) inhibitors and elucidate their mechanisms resistance. Between 2017 2020, 157 seed samples collected nationwide a dose-response with various ALS-inhibiting herbicides was performed glasshouses. This revealed 14 resistant R/S ranges 2.3–1450.2, 9.5–398.5 2–2.5 for tribenuron, iodosulfuron florasulam, respectively. Eight them cross-resistant both tribenuron iodosulfuron, three one singly respectively, population had reduced florasulam only. In population, cross-resistance identified. ED50 many susceptible ALS close half recommended dose tested. seven out eight analysed, target-site Six amino acid replacements found (Ala197, Arg197, His197, Leu197, Ser197 Thr197). inhibitors, no mutations gene detected. An efficient anti-resistance strategy needed reduce development herbicide Poland.