Agrotechnology

Pre and post plant herbicidal weed management in transplanted rice

2^nd International Conference on Agricultural & Horticultural Sciences

Radisson Blu Plaza Hotel, Hyderabad, India February 03-05, 2014

Kishor Mote, A Christopher Lourduraj, P Murali Arthanari and C N Chandrasekhran

Accepted Abstracts: Agrotechnol

Abstract:

Field experiment was conducted from September 2011 to January 2012 at Wetland farm of Tamil Nadu Agricultural University, Coimbatore to study pre and post plant herbicidal weed management in transplanted rice. The experiment was laid out in a factorial randomized block design with three replication and two factors viz. pre-plant herbicide application (with and without glyphosate at 0.75 kg a.i ha -1 ) and pre emergence/early post emergence herbicide treatments consisting PE butachlor 1.25 kg a.i ha -1 , pretilachlor 0.75 kg a.i ha -1 , almix 20 g ha -1 on 3 DAT followed by hand weeding at 40 DAT, EPOE Bensulfuron methyl + pretilachlor (6.6 GR) @ 0.06+0.60 kg a.i ha -1 at 10 DAT, hand weeding twice at 20 and 40 DAT and unweeded control. Pre-plant application of glyphosate 0.75 kg a.i. ha -1 recorded lower weed density and dry weight compared to non application of glyphosate. Among the weed control treatments, at 20 DAT, pre emergence application of pretilachlor at 0.75 kg a.i ha-1 + HW at 40 DAT significantly reduced the weed density and dry matter production. At 40 DAT and 60 DAT, Bensulfuron methyl + pretilachlor (6.6 GR) @ 0.06+0.60 kg a.i ha -1 at 10 DAT recorded lower weed density and weed dry weight, followed by pretilachlor 0.75 kg ha -1 + HW at 40 DAT and HW twice at 20 and 40 DAT . At 20 DAT, maximum weed control efficiency (WCE) and minimum nutrient uptake by weeds were recorded in pretilachlor 0.75 kg ha -1 + HW at 40 DAT, followed by butachlor 1.25 kg ha -1 + HW at 40 DAT. At 40 and 60 DAT, EPOE application of Bensulfuron methyl + pretilachlor (6.6 GR) @ 0.06+0.60 kg a.i ha -1 at 10 DAT, recorded the higher weed control efficiency and lower uptake of nutrient by the weeds, followed by pretilachlor 0.75 kg ha -1 + HW at 40 DAT. Among the different weed control methods, highest net return and B: C ratio was obtained with EPOE application of Bensulfuron methyl + pretilachlor (6.6 GR) @ 0.06+0.60 kg a.i ha -1 at 10 DAT (Rs.33120 and 2.19, respectively), followed by pretilachor at 0.75 kg a.i ha -1 + HW at 40 DAT (Rs.30054 and 2.11, respectively).