Effects of co-inoculation with efficient microorganisms and fertilization in the soybean seeding furrow in a sugarcane field renovation area

There are not many studies comparing the synergistic effect of co-inoculation with microorganisms and fertilization in the seeding furrow on soybean yield in a sugarcane crop rotation. Thus, the objective in this study was to evaluate the effect of co-inoculation with efficient microorganisms, in the presence and absence of fertilization in the soybean seeding furrow in sugarcane field renovation areas. The experiment was conducted in Iturama, MG, Brazil. The treatments were obtained by combining co-inoculation with beneficial microorganisms in the seeding furrow, as follows: Control, without co-inoculation, used as a standard by soybean producers in the region; Program 1, a mixture of various microorganisms (Azospirillum brasilense Abv5 Abv6 + Bacillus amyloliquefaciens + B. subtilis + Trichoderma asperellum + T. koningiopsis + Purpureocilium lilacinum + Isaria fumosorosea); BiomaPhos® - B. subtilis + B. megaterium; EM Solo AMtec® (B. mycoides + B. subtilis + Trichoderma spp. and Bradyrhizobium spp). These treatments were combined with the presence or absence of fertilization in the seeding furrow, forming a 4×2 factorial arrangement with 4 replications in a randomized block design. The co-inoculation with microorganisms did not increase soybean grain yield. A decrease in yield was observed with the use of Program 1, an effect that was mitigated by fertilization in the seeding furrow. It was concluded that the use of efficient microorganisms neither increased soybean yield nor served as a substitute for fertilization in the seeding furrow.