Effect of Tillage Practices and Weed Management in Sugarcane with Special Reference to Cynodon dactylon

Abstract

Sugarcane productivity is adversely affected by weed infestation, particularly by persistent perennial weeds such as Cynodon dactylon. Its extensive rhizomatous and stoloniferous growth makes effective control difficult, highlighting the need to evaluate integrated tillage and weed management practices for improving weed suppression and sugarcane productivity. An experiment was conducted to study the effect of tillage and weed management practices in sugarcane with special reference to Cynodon dactylon at Main Sugarcane Research Station, Junagadh Agricultural University, Kodinar, Gujarat from 2017-18 to 2019-20. The experiment comprised four tillage practices T₁: Control (Farmer’s practice), T₂: MB ploughing f/b rotavator, T₃: Glyphosate @ 2.5 kg/ha (pre-planting) f/b MB ploughing, and T₄: Paraquat @ 0.5 kg/ha (pre-planting) f/b MB ploughing in the main plot and three weed management treatments W₁: unweeded check, W₂: Glyphosate @ 2.5 kg /ha at 45 DAP (post-emergence directed spray) and W₃: Fenoxaprop-P-ethyl @ 75 g/ha at 45 DAP (post-emergence directed spray) in the subplot. The experimental results revealed that a significantly higher cane yield (126.08 t/ha) was recorded under the treatment combination of glyphosate @ 2.5 kg/ha (pre-planting) f/b MB ploughing + glyphosate @ 2.5 kg /ha at 45 DAP post-emergence directed spray (T3W2) than under all other treatment combinations, but it remained at par with T3W3 (glyphosate @ 2.5 kg/ha (pre-planting) f/b MB ploughing and fenoxaprop-P-ethyl @ 75g /ha at 45 DAP post-emergence directed spray) which produced a cane yield of 123.43 t/ha. The quality parameters of sugarcane, such as brix, sucrose, purity, CCS and extraction per cent did not differ significantly among the different tillage practices. All quality parameters, except purity and extraction per cent, showed significant changes due to different weed control treatments. The highest weed control efficiency of Cynodon dactylon was recorded with post-emergence directed spray of glyphosate (64.10 %) followed by fenoxaprop-P-ethyl (46.56 %). The highest per cent control of Cynodon dactylon (87.66 %) was observed under treatment combination T3W2 (Glyphosate @ 2.5 kg/ha (pre-planting) f/b MB ploughing + Glyphosate @ 2.5 kg/ha at 45 DAP post-emergence directed spray) followed by T3W3 (Glyphosate @ 2.5 kg/ha (pre-planting) f/b MB ploughing + Fenoxaprop-P-ethyl @ 75g /ha at 45 DAP post-emergence directed spray) i.e. 83.06 %, compared with other treatment combinations.