INFLUENCE OF DIFFERENT WEATHER PARAMETERS ON POPULATION OF MUSTARD APHID LIPAPHIS ERYSIMI (KALT.)
Department of Agronomy, Rajsthan College of Agriculture, Maharana Pratap University of Agriculture and Technology, Udaipur–313001
N.S. SOLANKI, S.L. MUNDRA AND O.P. AMETA
The mustard aphid, Lipaphis erysimi (Kalt), is one of the most nefarious biotic constraints of rapeseed–mustard. Mustard sown on 5th October (normal sowing) escaped from the attack of Lipaphis erysimi in Udaipur region of Rajasthan whereas, the crop with delayed sowing by 15 and 30 days than normal sowing resulted in significantly more aphid attack. Flowering and green seed stages were found sensitive stages for incidence and spread of aphids. The mean temperature of 13.7 to 17.2 oC and mean relative humidity of 54.5 to 60.0 % were found conducive for incidence of aphid attack under delayed sown crops. The peak infestation was observed when the mean temperature of 17.7 to 20.4 oC and mean relative humidity of 56.8 to 61.0 % prevailed during the period.