The research aimed to evaluate and characterize the biomass of leguminous residues, the natural arbuscular mycorrhizal (AM) fungus occurrence and the effect of leguminous on the nematodes (Pratylenchus spp.) in sugarcane crop. The experiment was carried out in Piracicaba, São Paulo State, Brazil. The soil was classified as Paleudalf and the sugarcane (Saccharum spp.) cultivar was IAC87-3396. The effects of previous cultivation of legumes were evaluated for five consecutive harvests. The treatments consisted of previous cultivation of legumes: peanut (Arachis hypogaea L.) cultivars IAC-Tatu and IAC-Caiapó, sunn hemp IAC 1 (Crotalaria juncea L.) and velvet-bean [Mucuna aterrima (Piper & Tracy) Holland], and a control treatment. We adopted the randomized block design with five replications. The legume most productive was sunn hemp IAC 1 with 10.264 kg ha-1, followed by velvet-bean with 4.391 kg ha-1 and peanuts IAC-Caiapó and IAC-Tatu with 3.177 kg ha-1 and 1.965 kg ha-1, respectively. The peanut IAC-Caiapó and velvet bean were the leguminous crops that resulted in the greater percentage of AM fungus. The lowest population of Pratylenchus spp. was found in the treatments with peanut IAC-Tatu and IAC-Caiapó. After five harvests, sunn hemp was the leguminous crop that induced the greatest sugarcane yield, with 30% increase in cane yield and 35% in sugar yield.
Saccharum spp.; Arachis hypogaea L.; Crotalaria juncea L.; Mucuna aterrina (Piper & Tracy) Holland; Pratylenchus spp.; green manure
