BIOINOCULAÇÃO COM Bacillus spp. E SEUS EFEITOS FISIOLÓGICOS NO DESEMPENHO DE PLÂNTULAS DE MILHO

Abstract

The growing demand for sustainable alternatives in agriculture has stimulated the use of plant growth-promoting microorganisms as a strategy to optimize the initial performance of crops. In this context, the objective was to evaluate the initial physiological effects of applying a commercial bioinoculant containing Bacillus spp. to maize seedlings (Zea mays L.) grown in sterile sand under controlled conditions. The experiment was conducted at concentrations of 0 (water); 50; 100; 150 and 200 µL and with four replicates. Morphological (emergence, root and shoot length and dry mass), physiological (chlorophyll a fluorescence and gas exchange), anatomical and histochemical variables were analyzed using PCA and Pearson correlation. The application of the 100 µL dose of the bioinoculant promoted a higher percentage of emergence, reaching 85%, an increase in the root system, biomass accumulation, and greater photochemical efficiency (Fv/Fm). Higher doses resulted in lower physiological performance and anatomical changes indicative of stress. Principal component analysis highlighted 100 µL as the dose with the strongest association between variables favorable to plant growth and development. Furthermore, a strong positive correlation was observed between photosynthetic yield and root growth. It is concluded that the 100 µL dose stood out as the most efficient, promoting a balance between root growth and photochemical efficiency. The proper application of bioinoculants represents a biotechnological approach capable of optimizing the initial establishment of corn, contributing to more efficient and sustainable production systems.