CURRENT STATUS OF BROWN LEAF SPOT IN RICE GROWING AREAS OF PUNJAB, PAKISTAN

Abstract

Brown leaf spot (BLS), a disease caused by the fungus Bipolaris oryzae (teleomorph: Cochliobolus miyabianus), is a major economic concern in rice-growing regions around the world including Pakistan, but it has gotten little attention in Pakistan. All well-known Basmati rice cultivars are affected by BLS. During 2020-21, surveys were conducted in nine rice-growing districts of Punjab province, Pakistan, from various fields of rice, infected samples were collected. BLS was found in all of Punjab's surveyed districts. According to the findings, eighty-five rice fields were surveyed, and 81 were found to be infected with BLS. Gujranwala has the highest BLS incidence (51%), Hafzabad (50%), and Narowal (47%). The highest severity rate was 75% in Super rice in district Gujranwala at Nathu Siwiya road, while the lowest was 5% in basmati rice in Gujrat. Based on morphological characterization, the pathogen was identified as B. oryzae. The findings showed that BLS has been present in rice-producing regions of Pakistan, particularly in the Basmati region of Punjab, for many years. To reduce inoculum levels and yield losses, resistant Basmati cultivars must be introduced.