Epidemiological studies on powdery mildew of vegetable pea

Abstract

The disease epidemiology of Pea Powdery mildew caused by Erysiphe pisi DC was studied during 2013-14 winter/spring season. The results revealed that, the first appearance of powdery mildew was observed 1st week earlier in variety Pant Vegetable Pea and Azad-P-3 during winter 2013-14. Erysiphe pisi DC can grow at wide range of temperatures during the cropping period having maximum temperature ranges from 27.60C to 30.60C and minimum temperature from 9.70C to 16.70C. The pathogen required high relative humidity during morning ranged from 83% to 93% and relative humidity during evening ranged from 23% (5th SMW 2014) to 47% (2nd SMW 2014). Increase in PDI was maximum in temperature ranges from 28.5- 30.00C (maximum) and 13.1-14.20C (minimum) temperature, wind velocity 1.6 Kmph and 68% average relative humidity. A positive correlation occurred between powdery mildew severity and temperatures, wind velocity in the varieties. However, the correlation with relative humidity was negative and significant except in varieties.