Selection of Rhizobia strains for development seedlings of leucaena (Leucaena leucocephala (Lam) De Wit.) in Red-Yellow Ultisol

Abstract

The study aimed at to evaluate the answer to the inoculation and to select efficient strains in the symbiotic fixation of N2 in leucena seedlings in Yellow Red Ultisol, under nursery. The individual inoculation of 12 strains of rhizobia homologous of the collection of INPA, a treatment was evaluated it controls and one that received N-mineral (urea, 80 kg ha-1). The design was random entirely, with 8 repetitions. After 74 days in nursery, the best strains were INPA 935 and 936 that favored the development of the biomass of the seedlings and the strain INPA 897 with high capacity infective showed for high nodule number formed. Two other strains also present potential for new tests as inoculant: INPA 899 and 937. The plants inoculated with INPA 935 produced dry biomass of the aerial biomass 30,8 and 45,0 % larger, that the treatments witness and with N. The rate of nodulation of the seedlings was of 98,6 % (n=112). The rates of foliar nitrogen they were high, with average of 43,6 g kg-1, with medium concentration of N in the leaves of 4,4 %.