Effects of Triazole and Strobilurin-Based Fungicides on Fusarium culmorum on Wheat

Fusarium culmorum is an important pathogen, that causes pre and post-emergence death in seedlings from both seed and soil-borne sources, in addition to causing root, crown root and wheat head infections on wheat. Treatment of seeds with fungicides is especially important to inhibit seed originated seedling infections when cultural methods are ineffective against the infection of the pathogen in root and crown root and the lack of completely resistant wheat cultivars against this pathogen. The efficiency of fungicides with prothioconazole + tebuconazole and triticonazole + pyraclostrobin active ingredients, licensed on Fusarium spp. in seeds, on seed originated seedling infections of F. culmorum is determined in vitro and in vivo conditions. Seeds of Flamura-85 bread wheat cultivar, naturally infected with F. culmorum S-14, were used in this study. The effect of treating seeds naturally infected with F. culmorum S-14 with fungicides on seed germination, root length, coleoptile length and disease severity was determined in the experiment in vitro. Germination rate of the seed was determined as 68% for triticonazole + pyraclostrobin and 43% for prothioconazole + tebuconazole, while disease severity was 42.70% and 61.30%, respectively. While both fungicides were determined to be effective on the disease severity, the effect of triticonazole + pyraclostrobin on disease severity was found to be higher than prothioconazole + tebuconazole. Because of the higher rate of effectiveness of triticonazole + pyraclostrobin to prevent seed-borne infections in vitro conditions, it was determined that the fungicide causes an increase in germination rate with wet and dry weight of the seed, while significantly decreasing the disease severity, in the tests to determine the effectiveness of the fungicide in vivo conditions.