Effect of weather parameters, host resistance and sowing date on disease severity and temporal dynamics of Fusarium wilt in chickpea (Cicer arietinum L.)

Fusarium wilt incited by Fusarium oxysporum f. sp. ciceris is an economically damaging disease of chickpea (Cicer arietinum L.). Field experiments on epidemiological studies revealed that sowing during second fortnight of November curtailed the disease severity index (22.50 and 20.83% during 2018-19 and 2019-20, respectively) whereas, sowing during first fortnight of October enhanced the disease severity index (34.86 and 30.41%). The area under disease progress curve was significantly higher in susceptible variety JG 62 and was the least in resistant variety HC 1. The correlation analysis exhibited positive correlation of disease severity index with maximum and minimum temperature while negative correlation with relative humidity morning and evening, irrespective of date of sowing. The principal component analysis depicted resistance index, sowing time and weather parameters as positional factors in determining Fusarium wilt progression.  In susceptible variety, Gompertz model was the best fitted model for simulating the Fusarium wilt epidemic over time.