Inoculação de sementes de feijão e milho com bactérias promotoras de crescimento vegetal

Abstract

The inoculation of bacteria that promote plant growth can improve the development of plants, regardless of their origin isolation, acting by different mechanisms, such as nitrogen fixation, phytohormones production, inorganic phosphate solubilization, production of quorum sensing molecule and still the phytoremediation. Corn (Zea mays L.) is one of the most cultivated grasses in the world and is considered one of the oldest and studied cultures. The beans (Phaseolus vulgaris L.) is consumed on every continent and has an important role in the Brazilian food, and is one of the agricultural products of greater economic and social importance in Brazil. Based on the foregoing, the objective of this work was to evaluate the performance of different bacterial genera, previously characterized with plant growth promoting characteristics, the seed germination in the laboratory, the emergency and development in the greenhouse. To this 10 bacterial strains of Bacillus sp, Stenotrophomonas sp.. Rhizobium sp., Pantoea sp. and Pseudomonas sp. were inoculated in corn and bean seeds and germination evaluated in germitest paper, following recommendations of the Rules for Seed Analysis. Moreover, inoculation with bacteria treatment of 4 plus a control (no inoculum bacterino) and an additional control (NPK) was carried out on corn seeds and analyzed in the greenhouse. The Bacillus sp., Pantoea sp., Rhizobium sp. and Stenotrophomonas sp. strains influenced the bean sproutingRegarding germination in maize, the bacteria Bacillus sp., Pantoea sp., Rhizobium sp. and Stenotrophomonas sp. influenced the germination, can be seen that the shoot fresh weight characteristics, dry weight of root and shoot, and shoot and root length were higher than the control when compared with the treatments of different bacterial inoculants. The experiment in greenhouse showed that UAGC863 strains (Bacillus sp.), UAGC62 (Pantoea sp.), UAGC738 (Rhizobium sp.) and UAGC982 (Stenotrophomonas sp.) promoted positives interaction, stimulating the development of corn. It was observed that when a comparison between strains dry weight of roots and shoots were stimulated by Bacillus sp., At 45 days of cultivation and by the compound treatment of the mixture of strains after 75 days of culture. When the comparison was made regarding the NPK was observed that all strains promoted increase in root dry weight than chemical control at 45 and 75 days of culture. Compared to the control (without inoculum) height, fresh weight and dry root were significant at 45 days of cultivation, and 75 days after treatment with the mixture of strains showed better results for fresh and dry root weight. These results show the potential of different bacterial genera presented in this work in promoting plant growth in corn and bean plants.