Residual Effect of Preceding Rice Herbicide on Weed Control, Growth and Productivity of Succeeding Okra in Madurai District of Tamil Nadu

An experiment was conducted at Agricultural College & Research Institute, Tamil Nadu Agricultural University, Madurai during rabi 2016 with a view to study the residual effect of preceding rice herbicide on weed control efficiency, growth and productivity of succeeding okra. Rice herbicide residue exerted significant difference in grasses, sedges and broad leaved weeds density at 20 DAS. In grass, the lowest weed density of 11.67 weeds/m² was registered under residual effect of butachlor at 1.25 kg ha⁻¹ on 3 DAT fb HW on 40 DAT in rice + HW twice at 20 and 40 DAS in okra. Similar trend was also observed in sedges and broad leaved weeds. The same treatment recorded higher plant height of 21.7, 53.1 and 92.7 cm and DMP of 624, 3296 and 9481 kg ha⁻¹ at 30, 60 and 105 days respectively and the fruit yield of 15.37 t ha ⁻¹ were recorded. It is registered 83.0 and 97.8% higher fruit yield than residual effect of oxadiargyl loaded with zeolite on 3 DAT and oxadiargyl loaded with biochar on 3 DATrespectively.