Inhibitory effect of Quercus brantii L. extract on Meloidogyne javanica, the causal agent of Root-knot disease, in tomato plants

Root-knot nematodes are one of the most important plant parasitic nematodes. The damage of these nematodes on tomatoes is estimated about 20-30%. One of the latest methods for controlling pests and plant diseases is application of organic products and use of natural ingredients with microbial and herbal origin. In order to reduce the damage of root-knot nematode in tomato plants, the nematicidal effects of aqueous extract of oak (Quercus branti L.) were evaluated on root-knot nematode, Meloidogyne javanica in vitro as well as in greenhouse conditions. An experiment was conducted in a completely randomized design. The treatments consisted of 1- plant parts (leaf and fruit) 2- plant extracts (at five concentrations, 1%, 2%, 3%, 5% and 7% for laboratory tests, and 0.05%, 0.1%, 0.15%, 0.25% and 0.35% (g dry powder in 100 grams of soil) for greenhouse experiments). Extracts of different parts of both tested plants caused maximum mortality of the second stage larvae, at the rates of 5% and 7%. Leaf and fruit extract at the rate of 7% caused 100% larval mortality. In case of reproduction factor, none of treatments had hazardous effect on plant growth including root and shoot length, fresh and dry weight. Between all treatments, the best treatment was identified at the rate of 0.35%, which was effective enough against nematode and also had no harmful effect on the tested plant.