Supressão de Meloidogyne Javanica em tomateiro com aplicação de extratos de Agave Sisalana.

Abstract

In recent decades, the practice of monoculture and successive cultivation in the same area has favored the emergence and worsening of phytosanitary problems, including the presence of nematodes. In tomato crops, they have been one of the main concerns of producers, with direct and indirect damage, leaving the plants predisposed to the attack of several other pathogens. The management of phytonematodes in the tomato crop is almost always carried out with applications of chemical pesticides. However, there are numerous negative questions about the contamination of the agroecosystem and food. In this sense, the search for different alternatives that can help in the management of highly aggressive pathogens such as nematodes and low toxic action on other soil lives, is the object of research worldwide. Agave sisalana has been cultivated for a long time, mainly in the northeastern semi-arid region, for the exploitation of the fiber, however, other aptitudes have been studied, such as its antimicrobial action. In this sense, the objective was to evaluate the potential of agave extract in the control of Meloidogyne javanica in tomato. The experiment was carried out in a greenhouse and Phytopathology Laboratory of the Federal University of Campina Grande - UFCG, Campus Pombal, in a completely randomized design, with eleven treatments (0;10; 20; 30; 40; 50; 60; 70, 80, 90 and 100%), corresponding to the concentrations of agave extract, with 5 replications. Soil infestations were carried out in pots containing tomatoseedlings, with 5,000 eggs/larvae per pot with M. javanica species. After the tenth day of inoculation, treatments were applied, equivalent to 50 mL of agave extract. After 60 days of treatment application, the plants were evaluated for agronomic characteristics: plant height, root length, root volume, root fresh mass, shoot fresh mass and shoot dry mass. The following parameters were also evaluated for parasitism:egg mass, number of galls, juveniles and eggs in the soil, juveniles and eggs in the root, reproduction factor and number of nematodes per gram of tomato root. For plant height and shoot fresh mass, there were gains of 14.92% and 29.97% from the concentration at 10%, respectively. As for shoot dry mass, the increase was 77.30% and 51.91%, at concentrations of 90% and 100%, respectively. As for parasitism, concentrations above 10% were sufficient to reduce all the variables studied.