Efficiency of Fungicide Programs at Management of a Seed Born Disease Gummy Stem Blight [Didymella bryoniae (Auersw.) Rehm (Syn. Mycosphaerella melonis (Pass.) Chiu & J. C. Walker)] on Watermelon
Articles > Article · 2020
Authors: Ceren Cer, Necip TOSUN
The Journal of Turkish Phytopathology, Other Refereed National Journals, National, TR DİZİN (ULAKBİM), 2020, vol 49, pp 45-54
Summary
<p>In recent years, the usage of grafted seedling keeps an important place in vegetable production. In Turkey, there is no effective management way or registrated fungicide against to gummy stem blight, caused by Didymella bryoniae, cause to serious economical loses at the production of grafted watermelon seedling. In this study, the effects of 0.3, 1, 3, 10, 30, 100 µg/ml doses of 5 different fungicides on mycelial growth of 4 D. bryoniae isolates were determined under in-vitro conditions. Afterward, 2 different seed trials were established in which the artificially inoculated watermelon seeds sown into sterile peat and disease-free watermelon seeds were sown in the artificially inoculated peat with the disease agent, and 3 different active ingredients were applied under greenhouse conditions and their effectiveness was determined. At the last stage of the study, 2 different spraying programs were prepared by combining some plant activators with fungicides which are found effective under in-vitro conditions and applied to watermelon seedlings in pots under greenhouse conditions. In in-vitro experiment, pyraclostrobin (12.8%) + boscalid (25.2%) with ED50 value of <0.3 µg/ml and MIC value of 9 µg/ml gave the best result. In the seed trial azoxystrobin (6.64%) + metalaxyl-m (3.32%) + fludioxonil (1.11%) provided the best protection against the disease. And in the seedling trial established in pots under greenhouse conditions; 2 different spraying programs tried were found to be highly effective and approximately the same. As a result, it was seen that D. bryoniae can be controlled with effective seed and seedling applications. </p><p>Keywords: Watermelon, Grafted seedling, Didymella bryoniae, Gummy stem blight, Seed, Plant defence activator<br></p>