Determination of the Weed Species, Frequency and Density in Lentil Fields in Diyarbak？r Province

This study was carried out in order to determine the species, frequency and density of weeds in Diyarbak？r lentil fields and 61 lentil fields were investigated during the 2015-2016 production season. Seventy-one weed species (14 monocotyledons and 57 dicotyledons) belonging to 21 families were identified as the result of the surveys. When the distribution of the species determined in terms of families was examined, the families Poaceae (13 species), Asteraceae (12) and Brassicaceae (10) were in the top three. Sinapis arvensis (4.24 plant/m2 ), Ranunculus arvensis (3.84) and Galium aparine (3.70) were the first species according to their frequency of occurrence (≥ 70%). The weed species detected were compared with different studies using similarity index and 24 species were found different. On the other hand, Cuscuta spp. lentil area was recorded for the first time. The low similarity rates of weeds show that the agricultural and cultural measures (late planting, deep tillage and crop rotation) as well as the soil and climate factors and applied methods of management (manual harvesting, chopping and herbicide use) are inadequate