Efficacy of Trichoderma harzianum, as a biological fungicide against fungal diseases of potato, late blight and early blight

Abstract

This study was conducted at Rangpur area of Bangladesh to evaluate the performance of Trichoderma harzianum based bio-fungicide against late blight and early blight of potato. A commercial fungicide, Agrizeb (Mancozeb) 80 WP was applied for comparison. These fungicides were applied in potato filed already infected by late and early blight. Lycomax found most effective for controlling both late blight and early blight while Agrizeb found potent for early blight. After applying Lycomax, late blight infection in plant has not increased rather decreased to 20.0% from the existing 22.67% and leaf infestation reduced to 10.67% from the existing 13.33%. In contrast for Agrizeb, plant infection increased to 71.67% from the prevailing 22.0% and leaf infection increased to 73% from the existing 14.67%. Thus, Lycomax confirmed 79.09% reduction of plant infection and 89.04% reduction of leaf infection compared to control which was 25.09% and 25%, respectively for Agrizeb. For early blight, same dose of Lycomax also reduce plant infection to 1.67% from existing 14.67% and leaf infection to 8.0% from prevailing 13.33%. Plant infection decreased to 5.0% from existing 15.0% and leaf infection 13.33% from 14.67% for Agrizeb. Therefore, Lycomax provided 98.19% control of plant infection and 90.16% control of leaf infection while Agrizeb provided 94.58% plant infection and 83.61% leaf infection over control. Moreover, Lycomax confirmed 21.66 ton/ha and 22.0 ton/ha of potato yield recovering the late blight and early blight diseases, respectively. These results conclude that Lycomax can effectively be applied to control late blight and early blight diseases.