Estratégias tecnológicas com bactérias promotoras de crescimento de plantas na cultura do milho.

Abstract

The use of microorganisms, mainly, plant growth-promoting bacteria (PGPB) is a viable alternative for a more sustainable and balanced agricultural production without reducing the production and technological levels already achieved. The objective of this work was to evaluate the effect of inoculation of growth promoting bacteria on maize plants, submitted to two different inoculation methods in the seeds. The experiment was carried out in a greenhouse with eight treatments and four replicates. Three BPCV isolates were used, these being 710, Rec 14b and BR11080, and the combination between them to compose the treatments. The methods of inoculation consisted in placing the viable seeds directly into the inoculum (mode 1) and another inoculating non-viable seeds that were placed just below the viable corn seed at the time of sowing (mode 2), totalizing 64 experimental units. The aerial and root dry mass of the corn plants were evaluated, as well as the nutritional analysis of the leaves to quantify the nutrient content of nitrogen, phosphorus, potassium, calcium and magnesium. There were significant differences between the treatments and also between the two forms of inoculation, and mode 2 of inoculation allowed greater production of dry mass and greater absorption of phosphorus, potassium, calcium and magnesium in the plants when inoculated with the treatments composed by the isolates 710 and BR11080. The treatment composed of the BR11080 + Rec 14b isolates showed better means for absorption of potassium, calcium and magnesium when inoculated directly into the seeds. It was concluded that the plant response to association with microorganisms could be influenced by the mode of inoculation used and that the combination of PGPB isolates did not result in significant increases in the physiological and nutritional response of the culture when compared to the inoculation of only one isolated on the seed.