Effect of post-emergence herbicides on weed control in Teak (Tectona grandis Linn. f.) nurseries

The current investigation aims to assess the influence and suitability of post-emergence herbicides on weed management, germination and seedling development in teak nurseries. The teak drupes underwent soaking and drying processes for six days, followed by field emergence in a 10.5 m2 nursery bed after preconditioning on the seventh day. The experiment, replicated four times, involved the application of post-emergence herbicides two months post-sowing. A total of twenty-one treatments were implemented: T0 (Control), T1 to T4 (Halosulfuron methyl 75 % Water-dispersible Granule (WG) at rates of 45 g, 67 g, 90 g and 110 g/ha), T5 to T8 (Imazethapyr 10 % SL at rates of 156 mL, 234 mL, 312 mL and 390 mL/ha), T9 to T12 (Quizalofop 5 % Emulsifiable Concentrate (EC) at rates of 600 mL, 900 mL, 1200 mL and 1500 mL/ha), T13 to T16 (2,4-Dichlorophenoxy acetic acid 58 % Soluble Liquid (SL) at rates of 430 mL, 620 mL, 860 mL and 1070 mL/ha) and T17 to T20 (Oxyfluorfen 23.5 % EC at rates of 375 mL, 560 mL, 750 mL and 937 mL/ha). The experimental design utilized a randomized block layout. Weed species (including broad-leaved plants, grasses and sedges) present in the nursery were documented in random 1 m2 plots for each treatment thirty days post-herbicide application. The outcomes indicate that the post-emergence herbicide, imazethapyr 10 % SL at a rate of 234 mL/ha, demonstrates compatibility, effectively controlling monocot and broad-leaved weeds while promoting teak seedling germination and growth with minimal phytotoxic effects.