Influence of sedaxane on state of antioxidative and osmoprotective systems of corn seedlings under conditions of salt stress

Ukraine Fungicide Sedaxane (mix of trans - and cis -isomers of N-[2-(1,1  -bicyclopropyl)-2-yl-phenyl]-3-(difluoromethyl)-1-methyl-1-H-pyrazole-4-carboxamide), relating to inhibitors of succinate dehydrogenase, causes the wide spectrum of physiological reactions related to the shifts of hormonal balance and to the change of expression of large amount of genes in plants. Its influence on the resistance of corn ( Zea mays L.) seedlings of hybrids Ariosso and Rotango to the salt stress (germination of seeds on 100 mM NaCl solution) have tigated. Hybrid Rotango differed by higher salt resistance in comparison with the hybrid Ariosso that was revealed in smaller oppression of growth of shoots and roots under conditions of salt stress. Priming of seeds with Sedaxane in concentration of 0.1 mg/ml significantly softened the negative impact of salt stress on the linear growth and accumulation of seedlings biomass. At the same time the treatment with Sedaxane increased the growth of both shoots and roots in seedlings of hybrid Ariosso under the salt stress, and only shoots in hybrid Rotango. Higher value of superoxide dismutase (SOD) and guaiacol peroxidase activity in shoots under stress conditions were characteristic to hybrid Rotango in comparison with those for the hybrid Ariosso. Under the influence of Sedaxane at the impact of salt stress SOD activity increased in the seedlings of hybrid Ariosso. Activity of other antioxidant enzymes (catalase and guaiacol peroxidase) in variants with priming of seeds with Sedaxane in both hybrids almost did not change. Treatment of seeds of both hybrids with Sedaxane significantly increased the accumulation of proline and caused the tendency to increase in content of carbohydrates and anthocyans under the action of NaCl. Sedaxane also elimi-nated the increase in content of hydrogen peroxide affected by the salt stress in shoots of seedlings of both genotypes. It was concluded that the intensifying of accumulation of low-molecular antioxidants and osmolytes under the influence of Sedaxane can be one of the causes of increase in the salt resistance of corn.