Controle de Meloidogyne javanica em olerícolas por composto de resíduos de pequi

Abstract

Various agricultural residues have shown potential for control of nematodes, especially after composting. The pequi residues have several composts with various functions including phytotoxicity to pathogens. The objective of this study was to evaluate the effect of organic compost with pequi waste in control of M. javanica in vegetable crops. For that, three experiments were carried out in a greenhouse using cultures of tomato, okra and lettuce. In the preparation of the compost we used 'pequi' peel waste, manure and sugarcane straw. They were evaluated five doses of the compost in proportions of 0, 5, 10, 20 and 30 g dm³ and two additional controls: manure (20 g dm³) and mineral fertilizer (100 mg dm³³ N). Pots containing 3 dm³ of sandy soil, to which were incorporated the different treatments were infested with eggs of 5.000 M. javanica. Five days later, the seedlings were transplanted. The treatments were arranged in a randomized block design with ten repetitions. The evaluations were performed after 60 days of transplanting for tomato and okra, and 45 days for lettuce plant. In all studied crops, plant height, dry mass of shoots and fresh mass of root increased in function of doses of applied compost. For okra, tomato and lettuce plant, increasing doses of compost to the soil significantly reduced the number of egg masses, galls and eggs of M. javanica per gram of root.