Subprodutos orgânicos no controle de Nematoides de galhas em Tomateiro.

Abstract

Tomato (Solanum lycopersicum L.) stands out from other vegetables due to its socioeconomic importance and high production cost, mainly due to its high susceptibility to pests and diseases, such as meloidogynous diseases. The use of agro-industry by-products has become a promising alternative in the control of several plant diseases, as they present compounds with inhibitory effects on pathogens, in addition to minimizing environmental impacts through the indiscriminate use of chemical pesticides. Therefore, the aim of this study was to evaluate the potential of different organic by-products on the parasitism of two species of root-knot nematodes, Meloidogyne incognita and M. enterolobii on tomato plant. Two experiments were carried out in a Vegetation House at the Federal University of Campina Grande – CCTA/UFCG. Two experiments were carried out in a Vegetation House at the Federal University of Campina Grande – CCTA/UFCG. Each experiment was conducted in a completely randomized design. The first experiment had 11 treatments and 5 replications, corresponding to isolated and mixed by-products, diluted at 50% with water: 1) Manipueira; 2) Vinasse; 3) Agrave extract; 4) Manipueira + vinasse; 5) Manipueira + agave extract; 6) Manipueira + pyroligneous extract; 7) Vinasse + agave extract; 8) Vinasse + pyroligneous extract; 9) Agave extract + pyroligneous extract; 10) Water (positive witness) and 11) chemical (negative witness). In the second experiment, 12 treatments equivalent to the same by-products were used, with the addition of pyroligneous extract, isolated and mixed with each other, diluted to 25% with water. Tomato seedlings from the Santa Cruz Kada Gigante cultivating were produced in polystyrene trays. After the fifth day of transplanting, they were inoculated separately with 5000 eggs/larvae of each nematode species. Seventy-two hours after inoculation, treatments related to organic by-products were applied. Sixty days after inoculation, the vegetative development of the plants was evaluated as: plant height, shoot fresh mass, shoot dry mass, root fresh mass and root length. The following were also estimated: the number of galls, egg mass, eggs in the root, juveniles in the root, juveniles in the soil, and nematodes per grams of root and reproduction factor. The by-products expressed different reactions in the tomato plant regarding the management of parasitism for the two nematode species. In the first experiment, the by-products applied to M. incognita promoted a gain in plant height (55%) with the isolated treatments (Manipueira, Vinhaça and Agave). Pure manipueira provided an increase in shoot fresh mass (87.07%), shoot dry mass (95.95%), as well as for root fresh mass (78.93%) and radicle length (41.10 %). For parasitism, there was a reduction in all variables, regardless of treatments. The second experiment, with M. enterolobii, showed a significant gain for the plants. The by-products were efficient in all parasitism variables. The use of by-products demonstrates biocidal potential on root-knot nematodes in tomato plant.