Abstract

A field experiment was conducted during rabi season of 2011-12 at Pandit Jawaharlal Nehru College of Agriculture and Research Institute, Karaikal, Puducherry U.T. The experiment consisted of nine treatments laid out in randomized complete block design comprising of three pre- emergence herbicides alone or integrated with a hand weeding at 40 days after transplanting (DAT) and hand weeding twice. Maintaining weed free condition throughout the crop duration resulted in higher weed control efficiency by virtue of significantly lower weed density and dry weight. Economic analysis revealed that pre-emergence application of pyrazosulfuron ethyl (20 g ha-1) integrated with a hand weeding at 40 DAT was better in terms of net returns and B C ratio than the weed free and hand weeding twice. Unweeded control accounted for 44.2% yield loss in coastal ecosystem of Karaikal,Puducherry UT.

Keywords: Transplanted rice, Pre- emergence herbicides, Integrated weed management, Coastal ecosystem