Weed management in rabi groundnut (Arachis hypogaea) for Konkan region of Maharashtra

Abstract

A field experiment was conducted at Agricultural Research Station, Shirgaon, Tal. Dist. Ratnagiri (MS) on the lateritic soil during rabi 2009-12 to evaluate post emergence herbicides in rabi groundnut (Arachis hypogaea L.). The experiment comprised of twelve treatments of weed control replicated thrice in Randomized Block Design (RBD). The various weeds observed in groundnut field during rabi season were Digitaria sanguinalis (L.) Scoup, Eleusine indica (L.) Gaertn., Echinochloa crusgalli (L.) Beauv. and Cyperus difformis (L.) among the narrow leaved weeds were more rampart. The broad leaved weeds like Leucas aspera Spreng., Cleome viscose (L.), Amaranthus viridis (L.), Euphorbia hirta (L.), Eclipta prostrate (L.), Physalis minima (L.), Alternenthera sessils (L.), and Convolvulus arvensis (L.) marked their presence in good numbers. Post emergence application of quizalofop- p-ethyl @ 50 g a.i./ha along with pre emergence pendimethalin @ 1.0 kg a.i./ha gave significantly lower total weed density (52.1/m2), weed dry weight (12.1g/m2) and higher weed control efficiency (91.3%), which was at par with post emergence application of imazethapyr @ 75 g a.i./ha along with pre emergence application of pendimethalin @ 1.0 kg a.i./ha. Application of quizalofop-p-ethyl @ 50 g a.i./ha as a post emergence along with pre emergence application of pendimethalin @ 1 kg a.i./ha significantly increased the pod yield, haulm yield and kernel yields (2.57, 2.83 and 1.90 t/ha, respectively) and was at par with post-emergence application of imazethapyr @ 75 g a.i./ha in groundnut. Highest net returns ( 29,700/ha) and benefit: cost ratio (1:1.68) were obtained with application of pre-emergence application of pendimethalin @ 1 kg a.i./ha along with one hand weed- ing at 30 to 35 DAS followed by combination of pre-emergence application of pendimethalin with quizalofop-p- ethyl @ 50 g a.i./ha ( 26,551/ha and 1:1.55, respectively) and with imazethapyr @75g a.i./ ha ( 23,499/ha and 1:1.47, respectively).