Post-emergence herbicides on weeds and productivity of garden pea undermid-hill conditions of Himalaya

摘要

To standardize dose and time of application of post-emergence herbicides in garden pea (Pisum sativum var. hortense) under mid-hills of Himalaya, eleven treatments, viz. imazethapyr 100 and 150 g/ha at 20 and 40 DAS, quizalofop 25 and 37.5 g/ha at 20DAS, isoproturon 1.0 and 1.25 kg/ha at 40 DAS, pendimethalin 1.5 kg/ha (pre-emergence), hand weeding twice (30 and 60 DAS) and unweeded check were tested during the winter (Rabi) season of 2005-06 and 2006-07 at Palampur. The major weed flora was constituted of Phalaris minor, Avena fatua and Vicia sativa in both the year. Post-emergence application of all the herbicides except quizalofop 25 g/ha at 20 DAS and hand weeding twice resulted in significantly lower dry weight of weeds over pre-emergence pendimethalin 1.5 kg/ha. Higher doses of all the post-emergent herbicides were superior to their lower doses. Significantly lower dry matter accumulation of all the weed species and highest weed control efficiency was obtained with imazethapyr 150 g/ha (40 DAS). Imazethapyr 150 g/ha at 40 DAS resulted in maximum plant height, dry matter accumulation, crop growth rate, relative growth rate nodule count and weight and green pod and haulm yields. Weeds in untreated check reduced pea pod yield by 56.8% over thebest post-emergent herbicidal treatment (imazethapyr 150 g/ha at 40 DAS) in 2005-06 and 60.1% in 2006-07.