Crop-weed Association in Different Field Crops at Sirajganj District in Bangladesh

A survey was conducted at farmers fields in five upazilas of Sirajganj district to find out farmers knowledge on crop-weed association in different field crops, crop yield losses and weeds act as alternate hosts for insect-pathogen during 2019 to 2020 cropping seasons. Primary data were collected from the respondents through a well-oriented structural questionnaire. A total of 40 weed species, belong to 35 genera under 21 families, were identified from 8 different field crops. The highest crop-weed association was found in rice (40:192) and the lowest in mustard (106:50). The maximum weed management cost was occurred in rice (38,900 Tk. ha1). Weed caused 8 to 51% yield loss in different field crops. Our results revealed that Mutha emerged as the major noxious weed for six field crops of this district. Weeds acted as alternate hosts of various insects and pathogens. According to farmers opinion, weed is also used as fodder, mulch, compost, vegetables, fish feed, medicinal and ornamental purposes at their locality. Therefore, the present study provides information to extension workers and researchers about the noxious weeds and their crop-weed association, other harmful and beneficial effects of weeds, for better, sustainable, and eco-friendly weed management practices. [J Bangladesh Agril Univ 2021; 19(2.000): 215-222