Relationship between Ascochyta blight of chickpea with weather variables was worked out and it was validated under field situation for two seasons. Incubation period was longer during January (2–3 weeks) and it came down to 3–5 days in March and it was negatively correlated with temperature. The disease spread was also maximum during 10–12* standard meteorological weeks (SMWs) corresponding with period from mid-Mach to end-March when temperature was more suitable for disease development. A minimum of four hours of leaf wetness was required for infection and production of disease symptoms. Based on empirical data, significant correlations were worked out between disease development and weather variables such as maximum temperature, evening relative humidity and a function of these two factors formed a sound basis for development of prediction model.
Chickpea, Ascochyta blight, weather variables, prediction, empirical relationships, model
