Efeito do priming com óxido nítrico no desenvolvimento inicial de um híbrido de milho sensível à seca, em comparação à um híbrido tolerante

Abstract

Water scarcity is one of the main abiotic factors limiting productivity in corn (Zea mays L.). Water deficit is one of the main agents responsible for the decrease in corn production, reducing the growth and development of plants. Therefore, the objective of this work was to verify the role of priming with nitric oxide in increasing the tolerance to water deficit of seedlings of a corn hybrid sensitive to drought. To establish the priming, the seeds of the hybrid BRS 1010 were submitted to treatments with different concentrations of S nitrosoglutathione (GSNO) (0, 50 and 100 μM), and later planted in plastic gerbox boxes. To induce water deficit, the sand substrate was moistened with a 1 MPa mannitol solution, using 73.597 grams of mannitol per liter of distilled water. After ten days of cultivation in BOD, parameters of emergence, growth, photosynthetic activity and root morphology were evaluated. Seed priming was positive for seedling growth and shoot and root mass production at a concentration of 100 μM. Regarding the photosynthetic evaluations, for the photochemical and non-photochemical quenching, again the concentration of 100 μM caused an improvement in the photosynthetic efficiency of the seedlings exposed to the adverse condition. The other photosynthetic parameters showed no changes due to water stress and GSNO application, as well as for root morphological analysis in general. Therefore, it can be concluded that the concentration of 100 μM was the most effective to act on some effects of water stress in the BRS hybrid, and the use of priming at this concentration is recommended.