Effects of Host Plant Resistance and Fungicide Applications on Ascochyta Blight Symptomology and Yield of Chickpea

Ascochyta blight (AB), caused by the pathogen Ascochyta rabiei, is a major threat to chickpea production worldwide, causing major yield losses and decreasing quality. Control of AB requires integrating pest management options including resistant cultivars and fungicide applications. To address this, fungicides with different modes of action were evaluated on three chickpea cultivars with differing levels of susceptibility to AB under irrigated and dryland conditions in 2015 to 2017. The fungicides were applied once or twice and compared with a no-fungicide application control on AB score and yield. The mean grain yields across locations and years were 1,753, 1,283, and 981 kg/ha, with a corresponding AB mean score of 2.6, 3.2, and 3.3 on 0 to 7 scale (where 0 is no disease and 7 is completely dead) for the moderately resistant, moderately susceptible, and susceptible chickpea cultivars, respectively. Fungicide application was not enough to control disease throughout the season. The use of AB-resistant cultivars had the most significant impact on minimizing the disease and maximizing yield, irrespective of year and location. This study supports previous research indicating that planting AB-resistant chickpea cultivars is essential for disease control, regardless of the fungicides applied.