Weed management in sugarcane (Saccharum officinarum L.) through herbicides and intercrops

Abstract

The present study was conducted to understand the effect of different weed management techniques i.e., hoeing, h~rbicides and intercropping systems on weed control, yield and quality of sugarcane. The field experiment was conducted at Anjanile, Chittur taluk of Palakkad district during 2002-03. Herbicide treatments were atrazine 2 kg ha-I as pre-ernergence (PE) fb hoeing and earthing up at 90 DAP, oxyfluorfen 0.20 kg ha' as pre-emergence (PE) fb 2,4-0, ametryn 2.0 kg ha' as PE fb 2,4-0 and' glyphosate I kg ha-I at 20 OAP fb 2,4-0 at 60 OAP. The intercropping treatments consisted of blackgram incorporation at 45 DAP, sunhemp incorporation at 45 OAP and its bhusa incorporation, daincha desiccation by 2,4-D, and sunhemp desiccation by 2,4-0. . . The major weed species in this experiment were Portulaca oleracea. Mollugo pentaphylla. Trianthema portulacastrum and Ageratum conyzoides. The population as well as dry matter production of weeds could be effectively controlled by the pre-emergence application of atrazine, ox.yfluorfen or ametryn fb 2,4-0 and also by growing sunhemp or daincha as intercrops. Higher weed . control efficiency and lower weed indices could be observed for herbicides, the atrazine and oxyfloufen; and for incorporation of balackgram, daincha or sunhernp. Pro-emergence herbicides and sunhcmp incorporation treatments gave better growth and yield parameters. In terms of cane production, oxyfluorfen 0.20 kg ha-I as pre-emergence fb 2,4-0 at 45 OAP and atrazine 2.0 kg ha-I fb hoeing and earthing up at 90 OAP werefound better. The overall results indicates that the weed problem in sugarcane could be effectively controlled by growing sunhernp as intercrop and incorporating it at 45 OAP or by spraying pre-ernergence herbicides viz., oxyfluorfen 0.20 kg ha-I as pre-ernergence (PE) fb 2,4-D. Among the intercrops, sunhemp incorporation at 45 DAP was found to be the best one. In terms of B:C ratio, sunhemp incorporation gave the highest value fb oxyfluorfen and 2,4-0. The results of

121 the study throws light. on the effective and economic weed control in sugarcanc by herbicides or .intercrops, which could replace hand hoeing, which is a costly affair. Considering the green matter addition and eco-safe weed control, growing sun hemp would be more preferable,