Author(s):

Sudharani JS, Madhukar Rao P, Sreedhar C and Thirumala Rao V

Abstract: Aerobic rice is one of the contingent production systems (Sreedevi et al., 2014). The major constraint in the success of aerobic rice is high weed infestation, yield loss from 50 to 100% has been reported in aerobic rice (Mishra and Singh 2007), A wide increase in grain yield (15–30%) by implementing different weed control practices elaborates the scope of weed management in aerobic rice. A study was conducted at Regional Agricultural Research Station, Jagtial, Karimnagar district of Telangana state in India, during kharif season of 2012 to investigate the most effective and economical weed management practice in aerobic rice cultivation. The study treatments were seven laid out in RBD viz. Pretilachlor + safener(0.4 kg a.i/ha at 3 DAS) fb hand weeding at 30 & 45 DAS, Bispyribac sodium (25 g a.i/ha at 20DAS), 2,4-D sodium salt (1.5kg a.i/ha at 35 DAS), Pretilachlor + safener(0.4 kg a.i/ha at 3 DAS)f b Bispyribac sodium (25 g a.i/ha at 20 DAS), Pretilachlor + safener (0.4 kg a.i/ha at 3 DAS), f b 2,4-D sodium salt(1.5kg a.i/ha at 40 DAS), Un weeded control and Weed free check (3HW at 20, 35 & 50 DAS). Results of the experiment depicted that highest grain yield (3456kg/ha) could be obtained with hand weeding thrice at 20, 35& 50 DAS, however most economical weed management practice was integrated weed management with pre emergence herbicide Pretilachlor + safener (0.4 kg a.i/ha at 3 DAS) fb hand weeding at 30 & 45 DAS which recorded higher net returns and BC ratio of 2.2. Chemical or integrated weed management practice with post emergence herbicides Bispyribac sodium (25 g a.i/ha at 20DAS),or 2,4-D sodium salt (1.5kg a.i/ha at 40 DAS) were not economical which recorded negative BC ratio. And a reduction in yield to the tune of 85.5% was noted under un weeded control.

Pages: 1050-1053  |  868 Views  228 Downloads

Download (489KB)