Evaluation of Pre and Post Emergence Herbicides in Greengram (Vigna radiata L.) during Kharif and Rabi Seasons in the Uplands of Krishna Zone of Andhra Pradesh

Abstract

Background: Greengram crop is grown round the year as a catch crop in different cropping systems of the uplands of the Krishna Zone of Andhra Pradesh. The practice of application of pre emergence herbicide like pendimethalin is very popular with the farmers for the control of weeds in the uplands, both in kharif and rabi seasons. Further spraying of a selective post emergence herbicide is also practiced by farmers. However, some of the weeds of kharif viz., Phyllanthus maderaspatensis and rabi viz., Chrozophora rottleri could not be controlled with these herbicides due to their late emergence or due to development of partial resistance to these herbicides. Certain new pre (PE) and post emergence (PoE) herbicides viz., pendimethalin 30% + imazethapyr 2%, acifluorfen sodium 16.5% + clodinafop propargyl 8%, fomesafen 11.1% + fluazifop -p-butyl 11.1%, are recommended in crops like soybean and groundnut. However, there is need to test these herbicides available in market for their suitability to control the weeds in greengram. Methods: A field experiment was carried out at Regional Agricultural Research Station, Lam, Guntur, Andhra Pradesh, with an objective to evaluate selected PE and PoE herbicide mixtures in greengram managing the major weeds of greengram grown in vertisols of Krishna Zone of Andhra Pradesh during Kharif and rabi seasons of 2018 under upland conditions. Result: Among the two PE herbicides tested on greengram, pendimethalin 30% + imazethapyr 2% @ 0.75 + 0.05 kg/ha was found to be more effective in reducing the weed density and dry matter compared with pendimethalin 30% @ 0.75 kg/ha. The PoE herbicide mixtures tested viz., fomesafen 11.1% + fluazifop -p-butyl 11.1% @111g/ha, propaquizafop 2.5% + imazethapyr 3.75% @ 50+75 g/ha were on par with imazethapyr 10% @ 50g/ha in controlling the weed population without having any adverse affect on the growth and yield of greengram during kharif and rabi.