Consórcio de bactérias promotoras de crescimento na cultura do morangueiro

Abstract

Bacteria are microorganisms capable of providing the development of vegetables from the availability of nutrients and metabolites, being important for sustainable agriculture. Strawberry cultivation occupies an area of more than 4300 hectares in Brazil, and this production demands the use of a large amount of chemical inputs. The objective of this study is to evaluate the growth promotion capacity of selected bacteria, and after inoculating them in different combinations in strawberry seedlings, evaluating their beneficial effects. It is also intended to analyze the contribution of bacteria to the reduction of the total fertilizer requirement in the strawberry. The microorganisms used in this study were Azospirillum brasilense, Bacillus megaterium and Brevibacillus sp. In vitro tests were carried out to evidence the supply of nutrients (N, P, K and Ca), siderophores and indole acetic acid (IAA). The experiment was carried out in a greenhouse in a completely randomized design (CRD), with the inoculation of bacteria in strawberry seedlings in isolation, in pairs and in triples, where fertilization with 30% of N and P was also carried out. controls were non-inoculated plants fertilized with 100% and 30% of N and P demand. At the end of the experiment (138 days) weights and measurements were carried out regarding the length, fresh and dry matter of the roots, shoots and the total of the seedlings. It was seen that the microorganisms showed positive results in all aspects analyzed for the availability of nutrients and synthesis of IAA, however the production of siderophores was not observed. The results showed that the strawberry plants responded positively to inoculation. In general, most treatments obtained higher yields than the control fertilized at 30% without inoculation and similar to the control without inoculation with 100% fertilization. It was seen that the inoculum provided the crown development, root growth and biomass accumulation. In this way, the intermediary of microorganisms allows a reduction in fertilizer demand for the strawberry by up to 70% of the total, as its use leads to the development of the plant in yields comparable to complete fertilization.