Azospirillum brasilense FAVORS MORPHOPHYSIOLOGICAL CHARACTERISTICS AND NUTRIENT ACCUMULATION IN MAIZE CULTIVATED UNDER TWO WATER REGIMES

Abstract

The use of plant growth-promoting rhizobacteria (PGPR) is an important and promising tool for sustainable agriculture. The objective of this study was to evaluate the morphophysiological responses and nutrient uptake of maize plants inoculated with A. brasilense under two water conditions. The experiment was carried out in a greenhouse with ten treatments: five A. brasilense inoculants (Control, Az1, Az2, Az3 and Az4) inoculated in the seed and two water conditions - irrigated and water deficit. Treatments with water deficit were imposed at the V6 stage for a period of 15 days. The phytotechnical characteristics, gas exchange, root morphology, shoot, root and total dry matter, as well as nutrient analysis, were evaluated after water deficit. Azospirillum brasilense (Az1, Az2, Az3 and Az4) yielded higher growth, increased gas exchange and nutrient uptake under irrigation conditions. Inoculation by Az1 and Az3 benefited the root architecture of maize plants, with a greater exploitation of the soil profile by these roots. Water deficit caused a reduction in the development of maize plants. Inoculation by Az1, Az2 and Az3 can improve plant growth, nutrient uptake and mitigate the effects of water deficit in the development of maize plants.