MOITINHO, M. L. B.; http://lattes.cnpq.br/6731210640798112.; MOITINHO, Mirna Larissa Barbosa.
Resumo:
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.
