مرکز منطقه ای اطلاع رساني علوم و فناوري - Current State of Weed Management and Problematic Weeds in Cotton Fields of Diyarbakir

Abstract :

a survey questionnaire was conducted over 80 cotton farmers in 2016 to evaluate the weed problems in cotton fields of Diyarbakır. The survey included 16 questions on weeds, herbicides, tillage and crop rotation. The research showed that the most common weeds were common cocklebur (Xanthium strumarium L.), black nightshade (Solanum nigrum L.), groundcherry (Physalis spp.), redroot pigweed (Amaranthus retroflexus L.) and johnsongrass [Sorghum halepense (L.) Pers.] were 51, 22, 8, 5, 5% respectively. Only glyphosate used as a total herbicide prior to crop emergence (100%). Across the province, pendimethalin, fluometuron, benfluralin trifluralin (forbidden in 2013), metholachlor-S+benoxacor are used as preplant herbicides to control broadleaf weeds at 55, 33, 5, 2 and 1% respectively. Only fluometuron (6%) was applied as pre-emergence. It was detected that 88% ofgrowers prefered herbicides to control grass weeds. Expense, weed species, rain or irrigation, and crop rotation were considered for herbicide choice by 53, 19, 16, and 12% respectively. Soil tillage during season was applied twice (%78), three times (24%), only once (3%). Since effective control of perennial weeds such as johnsongrass and bermudagrass is not possible by hoeing, the hoeing is made for broadleaf weeds. The preceding crops were cotton (58%), maize (30%) and wheat (12%). This study suggests that it is important to improve weed control methods in cotton fields and to develop pre and post-emergence weed control strategies.