Weed Management Strategies for Organic Farming of Kharif Groundnut

The field experiment was conducted on medium black calcareous clayey soil at Organic Farm, Department of Agronomy, College of Agriculture, Junagadh Agricultural University, Junagadh (Gujarat) during kharif seasons of 2015 and 2016 to evaluate non-chemical weed management practices in groundnut.The experimental soil was slightly alkaline in reaction with pH 8.0 and EC 0.61 dS/m.It was medium in available nitrogen (235 kg/ha), low in available phosphorus (23 kg/ha) and high in available potash (385 kg/ha).The experiment comprised pre-sowing treatments (M1: Deep ploughing, M2: Stale seedbed and M3: Soil solarization) as main plots and post-sowing treatments (S1: Wheat straw mulch @ 5 t/ha, S2: Hand weeding & interculturing at 15, 30 and 45 DAS, S3: Weed-free check and S4: Weedy check) as sub plots were laid in a split plot design with four replications.The groundnut variety 'Gujarat Groundnut 20' was sown in June at spacing of 60 cm x 10 cm using seed rate of 120 kg/ha.FYM @ 10 t/ha was incorporated in soil at the time of preparatory tillage.For soil solarization, a light irrigation was applied and then the soil was covered with 25 micron LDPE sheet for 15 days during hot summer (May).Deep ploughing up to 20 cm depth was carried out using mouldboard plough.For stale seedbed, a pre-sowing irrigation was applied to allow weeds to grow.After 7 days germinated weeds were removed by