Chitin and chitosan on Meloidogyne javanica management and on chitinase activity in tomato plants

Abstract

This study evaluated the efficacy of chitin and chitosan on the control of M. javanica, on the increase of chitinolyctic microorganisms in the soil, on chitinase activity on tomato leaves and on plant development. The experiment was carried out by the application of the treatments at the time of tomato transplanting, via leaf spray (chitosan) or in soil (chitin) which was previously infested with M. javanica. The experimental design was completely randomized with seven treatments (combinations of chitin and chitosan) and ten replications. Evaluations were done 60 days after transplanting, determining the reproduction factor, number of eggs and juveniles per gram of fresh root, shoot height (cm), root system length (cm), root and shoot dry matter (g), chitinolyctic population of microorganisms in the soil (CFU/g soil), and chitinase activity in the leaves. Leaf-sprayed chitosan increased dry matter of tomato shoots. Soil-applied chitin, associated with leaf-sprayed chitosan, reduced M. javanica reproduction factor and its population due to an increase in chitinolyctic microorganisms in the soil, and in the activity of chitinase in tomato leaves 4 days after application.