Green manure in the management of Pratylenchus brachyurus in soybean

The aim of this study was to evaluate the effects of green manures on Pratylenchus brachyurus management in soybean. Two experiments were conducted at different periods using a fully-randomized design in a 6 x 2 factorial arrangement, with six plant species (maize (control), velvet bean, crotalaria, stylosanthes, pigeon pea and oil seed radish) and two cropping systems (incorporated and non-incorporated). Simulating crop succession, soybean was cultivated after different plant species, in 2-liter pots containing naturally-infested soil. Vegetative and nematological parameters were evaluated. No significant differences were observed among the treatments for shoot fresh and dry weight and the number of nematodes in 100 cm(3) soil. Velvet bean and pigeon pea increased root weight in experiments 1 and 2. All treatments reduced the number of nematode/g root compared to the control, with the best results obtained using velvet bean, crotalaria and stylosanthes. The interaction showed that incorporating the fresh weight of the shoots of pigeon pea and oil seed radish reduced the number of P. brachyurus compared to the non-incorporated system.