Salinity stress represents an obstacle for the production of plants of commercial interest, including sweet maize. Among the techniques used to suppress the effects caused by excess salts in the soil is the exogenous application of vitamins. Thus, the objective of this study was to evaluate the effect of the pre-sowing treatment of sweet maize seeds in solutions of thiamine, niacin and these two vitamins combined on the development of the plants irrigated with saline water. The treatments were composed by the 24 h pre-sowing treatment with water, thiamine solution (thiamine 100 mg L-1), niacin solution (niacin 100 mg L-1) and a combined solution with these two vitamins (thiamine 50 mg L-1 + niacin 50 mg L-1) irrigated with saline water. A control (pre-sowing treatment with water and irrigation with non-saline water) was also used. It was observed that salinity stress affects the sweet maize initial development. Application of isolate thiamine or niacin and its combined application improves the relative contents of chlorophyll ‘a’ and total, height of shoot, leaf number, diameter of stem and shoot, root and total dry matter, reducing dry matter losses by 8.89%, 25.46% and 39.60%, respectively. Soaking seeds for 24 h in thiamine and niacin solutions improve the initial growth of sweet maize plants under salt stress and a combined vitamin solution (thiamine 50 mg L-1 + niacin 50 mg L-1) effectively reduces the salt stress negative effect on the initial development of these plants.
Introduction. Plant growth-promoting rhizobacteria have been successfully inserted in agriculture, aiming to find a better balance between agricultural production and environmental protection. However, there is a restriction on its application concerning the exploited species since the focus is on large-scale grain production, practically excluding small and medium-sized farms. Literature. Studies on the application of Azospirillum bacteria in horticultural species are still scarce, compared with those aimed at grain production. However, it appears that these bacteria are beneficial to the development and production of vegetables, whether they produce leaves, stems, bulbs, flowers, fruits, roots, or tubers, and may result in monetary gains, especially for small and medium agricultural producers. Conclusions. The use of Azospirillum bacteria to increase the quality and quantity of products from horticultural species and establish an environmentally friendly practice is a reality. However, the development of research that defines the best strategies for using this technology must be carried out continuously, aiming at the best conditions for producers.