Effects of baobab (Adansonia digitata L.) in combination with Sporidiobolus pararoseus Y16 on the activities of the defense-related enzymes and the expression levels of defense-related genes of apples

摘要

The efficacy of antagonistic yeast Sporidiobolus pararoseus Y16 alone or in combination with baobab (Adansonia digitata L.) was studied for the expression levels of defense-related genes, oxidative stress and enzymes activity of apple fruits. The results revealed that the treatment of S. pararoseus Y16 at 1 x 10(8) cells/mL amended with baobab (AB) improved the enzyme activity and then increased the defense mechanism on apple fruit. Moreover, the results of the study showed that the combination of antagonistic yeast and AB led to an enhancement of the efficacy of enzymes of superoxide dismutase, polyphenol oxidase, peroxidase, catalase, phenylalanine ammonia lyase, and chitinase activity during the storage period. Furthermore, results showed baobab improved the oxidative tolerance of S. pararoseus Y16, which led to an enhancement of biocontrol activity of antagonist. The proper combination of S. pararoseus Y16 and baobab can thus provide an effective strategy to enhance the postharvest quality of fruits. Besides, gene expression levels of related-enzyme defense responses involved were used to investigate the mechanism of antagonistic yeast in response to the application of baobab in apple. The results exhibited that S. pararoseus Y16 amended with baobab had a significant effect on the induction of defense-related genes expression compared to the control. These findings showed that antagonist yeast treatments amended with baobab could be a promising method for enhancing defense mechanism of apple fruit.