Effect of Pendimethalin and Imazethapyr on Nodulation, Nitrogen Fixation and Nitrogenase Activity and Yield in Groundnut (Arachis Hypogaea L.)

Abstract

A field experiment was conducted at College of Agriculture, Rajendranagar, Hyderabad in kharif 2011 to study effect of Pendimethalin and Imazethapyr on nodulation, nitrogen fixation and nitrogenase activity in groundnut. Results indicated that Seed treatment with Rhizobium in groundnut significantly influence the total nodule number up to 45 DAS and active nodules throughout the crop growth period. Application of Pendimethalin doses did not adversely affect the number of total nodules or active nodule count. But, application of Imazethapyr at double dosage resulted in significantly lower total nodule and active nodule up to 45 DAS. Nitrogenase activity in groundnut increased up to 60 DAS and thereafter decreased gradually. Imazethapyr double dose adversely affected the nitrogenase activity up to 45 DAS which later on recovered from 60 DAS. Despite better weed control achieved in Imazethapyr double dose treatment, highest pod yield was recorded in Imazethapyr at recommended dose where seed inoculation was done compared to Imazethapyr double dose.