Ácidos orgânicos na qualidade fisiológica de sementes de arroz.

Flooding the soil for rice cultivation promotes anaerobic conditions that favor the production of short-chain organic acids, which can be toxic to the culture. This study aimed to evaluate the physiological quality of seeds of rice cultivar 'IRGA 424' subjected to stress by different organic acids. We studied three organic acids formed in the ground and five levels, namely: acetic, propionic, and butyric acid in doses 0, 4, 8, 12 and 16mM. The seeds were soaked in solutions and in the doses above, for a period of 90 minutes, after, were tested for germination and vigor (first count germination, shoot length and root and shoot dry mass and root). In evaluating the quality of the seed facing the stress by organic acids, the variable length of the roots was the most efficient to differentiate the toxicity by different doses of acetic acid, propionic and butyric. The butyric acid was the most damaging to rice seeds, affecting early development of seedlings of the cultivar 'IRGA 424'. [ABSTRACT FROM AUTHOR]