False cleavers (Galium spurium L.) with target-site resistance to ALS inhibiting herbicides in Greece

Galium spurium(Rubiaceae) is a frequent troublesome dicotyledonous weed species, usually controlled with ALS inhibitors, synthetic auxins and their mixtures. In 2016, florasulam+2,4-D failed to adequately control this species in cereal fields (Phthiotida, central Greece) prompting the current study. Seeds from three G. spurium populations (G2, G3, G4) with possible resistance and one from herbicide-free field borders (G1, reference) were collected. These were evaluated in a pot experiment for possible resistance to ALS inhibitors at 0, N and 4N (N= recommended field dose: florasulam+2,4-D 4.375+210 g/ha, florasulam 6.25 g/ha, mesosulfuron+iodosulfuron 7.5+7.5 g/ha) with four replicates (fiv…