Efficacy of New Herbicide Mixtures on Weed Control, Yield, and Economics in Transplanted Rice

Aim: To evaluate the efficacy of new herbicide mixtures on the weed control and performance of transplanted rice.

Study Design: Randomized Complete Block Design.

Place and Duration of Study: AlI India Coordinated Research Project on Weed Management, PJTSAU, Hyderabad between August to December, 2021.

Methodology: The efficacy of herbicide mixtures either ready mix or as tank mixtures were evaluated for effective and broad spectrum weed control in transplanted rice during kharif season, 2021 at AICRP on Weed Management, PJTSAU, Rajendranagar, Hyderabad. The experiment was laid out in a randomized complete block design with nine treatments and three replications. The treatments included five ready mixes (RM) one tank mix combination of new herbicides tested against one single herbicide, weedy check and hand weeding twice at 20 and 40 DAT.

Results: The results of the study revealed that bispyribac sodium 10% SC 25 g ha-1+ penoxsulam 1.02% (20 g ha-1) (tank mix) as post-emergence (POE) fb hand weeding (HW) at 40 DAT or penoxsulam 0.97% (20 g ha-1) + butachlor (38.8%) @ 820 g ha-1 (RM) as POE fb HW at 40 DAT or penoxsulam 1.02% (20g ha-1) + cyhalofop butyl 5.1% (100 g ha-1 ) (RM) as POE fb HW at 40 DAT or bensulfuron methyl 0.6% (60 g ha-1) + pretilachlor 6% (600g ha-1) GR (RM) as pre-emergence (PE) fb HW at 40 DAT were equally effective to hand weeding twice at 20 and 40 DAT with respect to suppression of weeds at 60 DAT. The yield attributes like a number of tillers/m2, panicles no, panicle length, grains panicle-1 and test weight were found to be higher with penoxsulam 1.02% (20 g ha-1) + cyhalofop butyl 5.1% (100 g ha-1) as POE fb HW at 40 DAT which also recorded higher grain yield, straw yield, gross returns, net returns and B-C ratio but it was found to be at par with other herbicide combinations.

Conclusion: It can be concluded that new herbicide mixtures either as ready mix or tank mix performed better than sole application or hand weeding alone.