Characterization of Weed Flora and Weed Management Practices in Rice under Different Cropping Systems in Western Gangetic Plains of India - A Case Study

Weed density and yield of rice in western IGP were examined in transplanted rice crop under rice-wheat, rice-pea-rice and rice-sugarcane-ratoon-wheat/fallow cropping systems. Echiflochloa crusgalli was dominant after rice-wheat and rice-pea-rice sequence, but it was completely suppressed after the sugarcane sequence. Among sedges, Fimbristylis milliacea was dominant after rice-wheat and Cyperus difformis after rice-pea-rice. In the sugarcane system, Cyperlls rotundus became the main weed. The yield loss from weeds in unweeded plots was highest in the rice-wheat system. followed by rice-pea-rice, and was least in the sugarcane system. Under fanners' weed management practices, there were yield losses due to weeds ranging from 13.1 to 22.4%. The total cost of weed management in transplanted rice was higher in rice-wheat system than in rice-pea-rice or rice-sugarcane system.