Distribution of Bipolaris maydis in southern Khyber Pakhtunkhwa (KP) – Pakistan and estimation of yield losses in maize crop

Abstract Maydis leaf blight, is an important disease of maize in Khyber Pakhtunkhwa (KP) – Pakistan. Knowledge about distribution pattern of a disease in an area is helpful for adoption of appropriate disease management strategy. Therefore, an extensive survey of the disease was conducted in southern districts of the province in 2020. Four union council in each district and five fields per union council were assessed in “X” shaped pattern. The highest disease incidence was found in district Bannu (78.05%) while least was detected in district Tank (39.84%). Similarly, the isolates of Bannu and Kohat districts exhibited larger colony diameter and spore size than other isolates. Yield losses were also assessed based on attainable and actual yield. The highest value of area under disease progress curve (AUDPC) was observed for cultivar Azam (229.7). Regression analysis indicated that a unit (1%) increase in AUDPC value increased yield loss by 7.6%.