Aerobiological studies on epidemiological factors influencing severity of early blight of tomato

The studies carried out to understand the epidemiology of Alternaria blight of tomato during 2011 revealed that per cent disease index (PDI) that progressed at linear rate throughout the plant growth, was negatively correlated with minimum temperature, relative humidity (morning and evening) and the rainfall, while it was positively correlated with the maximum temperature. The spore load of Alternaria solani in the open air, found maximum during October and November, showed positive correlation with the maximum temperature, and significant negative correlation with the minimum temperature and evening relative humidity.