Systems of Rice Intensification
PE pretilachlor + safner 0.45 kg/ha -1 on 3 DAS + roto cylindrical weeder weeding on 45 DAS in wet seeded rice resulted in excellent control of weeds like Echinochloa crusgalli, Panicum repens, Eclipta alba and Monochoria vaginalis and higher grain yield, net monetary returnand B:C ratio.
PE Pyrazosulfuron ethyl 10 % WP @ 150 g ha -1 on 3 DAT + hand weeding (HW) on 45 DAT. PE butachlor 0.75 kg a.i. ha -1 + bensulfuron methyl 50 g ha -1 on 3 DAT + HW on 45 DAT
Post – emergence herbicides
Increasing transplanting costs in southeast Asia have encouraged farmers to adopt labour-saving crop establishment techniques for rice, such as wet seeding. This practice has been accompanied by an increase in weed problems and a shift in the dominant species to grassy weeds. Other problems are encountered with wet seeding but weeds are the most severe and most widespread constraint. It is impossible to produce rice economically without a well-planned weed control programme. The problems caused by weeds in wet-seeded rice and ways of controlling them by preventive, ecological, managerial, physical and chemical means are discussed in this paper. Herbicides are the most cost-effective weed control method in wet-seeded rice but there is a need to reduce the almost total reliance on them for weed control; cultural practices need to be integrated with judicious herbicide use. Worldwide concerns over environmental issues also need to be addressed.