Energy budgeting of weed management in soybean

An experiment was conducted at ICAR-Directorate of Weed Research, Jabalpur during Kharif season of 2015 and 2016 in order to assess the energy budgeting of weed management in soybean cultivation. Ten treatments comprising of pendimethalin (750 g/ha PE), pendimethalin (750 g/ha PE) fb imazethapyr (100 g/ha at 20 DAS), pendimethalin (750 g/ha PE) fb 1 HW (at 20 DAS), metribuzin (500 g/ha), metribuzin (500 g/ha) fb imazethapyr (100 g/ha at 20 DAS), metribuzin (500 g/ha PE) fb 1 HW (at 20 DAS), imazethapyr (100 g/ha at 20 DAS), imazethapyr (100 g/ha at 20 DAS) fb 1 HW (at 40 DAS), 2 HW (at 20 and 40 DAS) and unweeded check were laid-out in randomized block design with three replications. Sequential application of pendimethalin 750 g/ha PE fb imazethapyr 100 g/ha at 20 DAS was found to be the most energy efficient weed management strategy and had maximum value of total output energy (71.90 x 10³ MJ/ha) and net energy returns (62.32 x 10³ MJ/ha). Other parameters like energy ratio (7.50), energy profitability (6.50) and human energy profitability (164.27) were also higher under the same treatment whereas, it recorded less specific energy (11.53 10³ MJ/ha) and energy intensity (0.48).