Effects of 24-epibrassinolide on root-knot nematode, Meloidogyne incognita (Kofoid & White, 1919) Chitwood, 1949 (Tylenchida: Meloidogynidae) in tomatoes

In this study conducted in 2020, three concentrations (1, 5 and 10 mu M) of 24-epibrassinolide were applied to seedlings of Lycopersicon esculentum Mill. (Solanales: Solanaceae) cv. H2274, which is susceptible to root-knot nematodes, by immersion, spray and irrigation, and its effects against root-knot nematode Meloidogyne incognita (Kofoid & White, 1919) Chitwood, 1949 (Tylenchida: Meloidogynidae) were investigated. One-thousand second stage juveniles of M. incognita, collected from cucumber roots in a greenhouse located in Cardak, Canakkale were inoculated on the roots of the plants per pot. After eight weeks, stem fresh weight, stem dry weight, root diameter and longest root length values, in addition to the stem length and stem diameter measured at the beginning and end of the experiment, were recorded. 24-Epibrassinolide, applied by an immersion method, gave similar or better results than the control even in the presence of nematodes. Distilled water plus nematode application showed the highest gall index whereas 5 mu M 24-epibrassinolide plus nematode application gave the lowest gall index. The lowest number of egg mass was also obtained from the same concentration of 24-epibrassinolide applied by immersion. As a result, 24-epibrassinolide showed a beneficial effect in terms of reducing the damage caused by the nematodes in tomato plants, depending on the concentration and application method.