Compatibility of Pre-mix Herbicide Mixture, Penoxsulam 1.02%+ Cyhalofopbutyl 5.1% OD with Bio-fertilizer Organisms and Biocontrol Agents

The study reports the results of in vitro experiments of compatibility of a new broad-spectrum herbicide mixture, penoxsulam + cyhalofopbutyl with Azospirillum lipoferum, Azotobacter chroococcum, Fraturaia aurantia and Bacillus megatherium and bio-control agent Pseudomonas fluorescens by disc diffusion method and Trichoderma viride by poison food technique. Results revealed that biofertilizer organisms A.lipoferum, A.chroococcum, F.aurantia and B.megatherium and bio-control agent P.fluorescens did not produce any zone of inhibition around the filter paper disc impregnated with 230, 240, 250, 260, 270, 280 and 290 Sl concentration of herbicide corresponding to herbicide dose of 115,120, 125, 130,135, 140 and 145 g ha⁻¹, indicating that penoxusulam + cyhalofopbutyl is highly compatible with these organisms.The radial colony diameter of T. viride was significantly influenced by different concentrations of penoxsulam + cyhalofopbutyl. With an increase in the concentration of penoxsulam + cyhalofopbutyl, a decrease in colony diameter was observed and the percentage growth inhibition was in the range of 51.85 to 74. 82, indicating that penoxsulam + cyhalofopbutyl is moderately toxic to T. viride. The in vitro results revealed the possibility of using penoxsulam + cyhalofopbutyl for weed control at recommended doses (125, 130 or 135 g ha⁻¹) under bio intensive disease management programme involving P.fluorescens and nutrient management programme involving A.lipoferum/A.chroococcum/B.megaterium/F.aurantia, suggesting the environmental safety of the herbicide.