Opções de bactérias na coinoculação na cultura da soja

Abstract

Associative and symbiotic microorganisms promote the sustainability of production in the soybean crop. Thus, the objective was to evaluate bacteria for co-inoculation in the promotion of growth and productivity of soybeans. Three experiments were carried out in the 2020/21 seasons, in a randomized block design with four replications. The first and second experiments were carried out at UFSM, with the following treatments (i): control without application of microorganisms; (ii): Bradyrhizobium japonicum (Bj); (iii): Bj + Azospirillum brasilense (Ab); (iv): Bj + Bacillus aryabhattai (Ba); (v): Bj + Bacillus megaterium (Bm); (vi): Bj + Biobokashi (Bi); (vii): Bj + Pseudomonas fluorencens (Pf) and (viii): Bj + Ab + Ba + Bm + Bi + Pf. The second experiment used the cultivar BRS 284 (Conventional) in a bifactorial 2 (with and without irrigation) x 8 (treatments described above). The third experiment was carried out in Ijuí-RS in a bifactorial [2 (without fertilization, 50% and 100% of the fertilization recommendation) x 8 (treatments described above)]. The variables evaluated were productivity and mass of one thousand grains, number and dry mass of nodules, soil cover rate, length, diameter, surface area and volume of roots per plant. Each soybean cultivar has different responses in the co-inoculation of microorganisms in different locations. The co-inoculation that stood out the most with different cultivars were Bj + P. fluorencens and Bj + B. aryabhattai, increased nodule mass, root growth and soybean yield under field conditions in different locations and with potential for partial replacement of fertilization mineral in fertile soil. The results of variables such as surface area and root volume had positive correlations in the three experiments.