Spatial distribution of ascochyta blight of chickpea [Didymella rabiei (Kovachewski) V Arx] and its association with biophysical factors in East Shewa Zone, Central Ethiopia

Ascochyta blight is re-emerging as a potential threat to chickpea production in Ethiopia. A field survey was conducted in East Shewa zone, central Ethiopia in 2019 to determine the spatial distribution and intensity of the disease and to investigate the association of the disease with biophysical factors and cultural practices. In total, 168 fields were assessed using purposive sampling. The disease was prevalent in 23 (33.82%) of the fields with a mean incidence and severity values of 15.20% and 26.21%, respectively. The average values of incidence ranged from 0% to 73.26%. Among districts, the highest prevalence and incidence of the disease was recorded in Boradistrict with 100% and 49.37%, respectively, whereas the lowest prevalence and incidence values of 10% and 3.9%, respectively were recorded in Adea district.The association of ascochyta blight incidence and severity with independent variables was examined using a logistic regression model with SAS GENEMODE procedure. The highest (>25.0%) ascochyta blight incidence and severity were highly associated with Bora and Lume districts, with fields previously sown with field pea and wheat, early August sown fields, and planting material sourced from other farmers. Efforts should be geared towards both Bora and Lume districts, crop rotation practice, late planting and use of the clean seed, along with other related farm practices to reduce ascochyta blightimpact in the study area.