Integrated weed management in garlic

Four herbicides (oxyflurofen 0.25 kg/ha, pendimethalin 1.50 kg/ha, trifluralin 1.50 kg/ha and metachlor 1.50 kg/ha) at recommended rates alone and at half of the recommended rates integrated with one hand weeding were compared with hand weeding 30, 60, 90 days after planting (DAP) and untreated check in silty clay loam soil during Rabi 2008–09 and 2009–10 at Palampur. Phalaris minor followed by Avena ludoviciana were the predominant associated weeds. All treatments resulted in significantly lower density of Phalais minor, Alopecurous myosuroides and Coronopus didymus. Metolachlor 1.50 kg/ha effectively reduced the density of Poa annua. Metolachlor + hand weeding, pendimethalin and pendimethalin + hand weeding effectively reduced the density of Stellaria media. Integration of hand weeding with half dose of oxyflourfen, pendimethalin and metolachlor resulted in significantly higher yield of garlic than their respective higher dose alone. Weed index was lowest and weed management index (WMI), agronomic management index (AMI) and integrated weed management index (IWMI) were highest under pendimethalin + hand weeding. Herbicide efficiency index (HEI) was highest with oxyflourfen + hand weeding. Pendimethalin + hand weeding gave highest net return due to weed control (NRwc) and was followed by pendimethalin and metolachlor + hand weeding. Pendimethalin gave highest marginal benefit cost ratio (MBCR) of 40.7 followed by pendimethalin + hand weeding and metolachlor + hand weeding. Weeds reduced the garlic bulb yield by 72.5% over the best treatment pendimethalin 0.75 kg/ha + HW.