Management of Azospirillum brasilense as a strategy for hydroponic green fodder production

Azospirillum brasilense is a nitrogen‐fixing bacterium that lives in association with plant roots. These bacteria stimulate plant growth by stimulating the production of hormones such as auxins, gibberellins and cytokinins. The production of these compounds increases the density and length of root hairs, the emergence of lateral roots and the surface area of ​​the root system, which increases the possibility of nutrient absorption. This study aimed to evaluate the effect of different forms of inoculation of A. brasilense in oat and maize for forage production in a hydroponic system. A completely randomized experimental design was used, with four replications. Four treatments were used, consisting of: T1: Control; T2: application of A. brasilense on seed; T3: foliar application of A. brasilense ; and T4: application of A. brasilense on seeds and foliar application. It was found that the application of the bacteria positively affects the growth of both species studied. However, application on seeds results in greater accumulation of dry mass in the roots, while foliar application or joint application results in greater development of the shoot and greater accumulation of fresh mass. Thus, it was concluded that the application of A. brasilense promotes plant growth through a combination of mechanisms, which results in a promising technique for obtaining higher yields in hydroponic green fodder cultivation.