Aerobic rice, Irrigation regimes, Weed management practices, Weed control efficiency, Weed index, Yield

The experiment was conducted on irrigation levels and integrated weed management practices during 2013 and 2014 at College of Agriculture, Hyderabad. Results revealed that higher grain yield was recorded with scheduling of irrigations at IW/CPE ratio of 2.0 (2.55 and 2.42 t/ha) due to accumulation of higher chlorophyll content and dry matter production of crop. Net returns (` 20656 and 18347/ha) and benefit cost ratio (1.7 and 1.6) was also higher with the same irrigation level. Scheduling of irrigations at IW/CPE ratio of 1.5 was the next best treatment in aerobic rice. Out of weed management practices tested, application of pendimethalin/butachlor as pre-emergence fb chlorimuron-ethyl + metsulfuron-methyl  post-emergence fb MW + HW at 45 DAS recorded lower weed population, weed dry matter and higher in weed control efficiency, which resulted higher chlorophyll and dry matter accumulation in crop and finally produced higher grain yield in pendimethalin 1.0 kg/ha as PE fb MSM + CME 4.0 g/ha at 25 DAS + MW fb HW at 45 DAS (2.15 and 2.05 t/ha) and butachlor 1.0 kg/ha as PE fb MSM + CME 4.0 g/ha at 25 DAS + MW fb HW at 45 DAS (2.08 and 1.98 t/ha). The same treatments recorded higher net returns and benefit cost ratio in pendimethalin 1.0 kg/ha as PE fb MSM + CME 4.0 g/ha at 25 DAS + MW fb HW at 45 DAS (1.6 and 1.5) and butachlor 1.0 kg/ha as PE fb MSM + CME 4.0 g/ha at 25 DAS + MW fb HW at 45 DAS  (1.6 and 1.5). Over the pooled years, significant interaction effect of irrigation scheduling at IW/CPE ratio of 2.0 along with application of pendimethalin/butachlor as pre emergence fb chlorimuron-ethyl + metsulfuron-methyl as post-emergence fb MW + HW at 45 DAS recorded lower weed dry matter (35.1/36.4) and higher grain yield (2.85/2.80 t/ha).