Radiação ultravioleta, desinfecção, desempenho fisiológico e indução de resistência em sementes de soja

Abstract

The objective of the present study was to evaluate the effect of the time of exposure to ultraviolet radiation, on the sanitization of Fusarium tucumaniae and Aspergillus spp., on the physiological quality of soybean seeds. To conduct the experiments, two seed lots (A) and five seed exposure times in ultraviolet radiation (0, 10, 20, 30 and 40 minutes) (B) were used (B), against the fungi Fusarium tucumaniae and Aspergillus spp. (C). The following variables were evaluated: field emergence, emergency speed index, emergency speed, 1st germination count, final germination, germination speed index, seedling length, dry mass, accelerated aging and seed health. Biochemically, the seeds were evaluated for embryo production in the germinative process of total proteins, chitinase and β-1,3-glucanase, total phenols and enzyme activity of Phenylalanine Ammonia lyase. The variables emergence in the field, emergence speed index, 1st germination count, final germination, accelerated aging and seed health did not meet the assumptions of the analysis of variance even after data transformation. It was possible to verify homogeneity between treatments for these variables. For the other variables, there was a significant statistical interaction between factors A and B for the variables shoot length, root length and seedling dry mass. Analyzing the factors in isolation, factor B was significant for the variables emergence speed, shoot length, root length and seedling dry mass, and factor C for the shoot length, root length and dry mass variables. seedling. As for the biochemical analyzes, it was possible to verify that for the phenol content variable, only the fungus factor presented significance. For FAL activity, there was a significant interaction between the batch and radiation time factors. As for the chitinase variable, there was no significance of the factors analyzed. For the protein variable, non-parametric analysis was performed, showing homogeneity between treatments. Β-1,3-glucanase expression was not observed. exposure to ultraviolet radiation within the analyzed periods and conditions tested was not effective on the sanitization of Fusarium tucumaniae and Aspergillus spp., requiring further studies to establish protocols that allow their replicability.