Nano-selenium repaired the damage caused by fungicides on strawberry flavor quality and antioxidant capacity by regulating ABA biosynthesis and ripening-related transcription factors.

Recently, studies have shown that pesticides may have adverse effects on the flavor quality of the fruits, but there is still a lack of appropriate methods to repair the damage. This study investigated the effects and mechanism of applying the emerging material, nano­selenium, and two fungicides (Boscalid and Pydiflumetofen) alone or together on the flavor quality and antioxidant capacity of strawberries. The results showed that the two fungicides had a negative impact on strawberry color, flavor, antioxidant capacity and different enzymatic systems. The color damage was mainly attributed to the impact on anthocyanin content. Nano­selenium alleviated the quality losses by increasing sugar-acid ratio, volatiles, anthocyanin levels, enzyme activities and DPPH scavenging ability and reducing ROS levels. Results also showed that these damage and repair processes were related to the regulation of flavor and ripening related transcription factors (including FaRIF, FaSnRK1, FaMYB10, FaMYB1, FaSnRK2.6 and FaABI1), the upregulation of genes on sugar-acid, volatile, and anthocyanin synthesis pathways, as well as the increase of sucrose and ABA signaling molecules. In addition, the application of nano-Se supplemented the selenium content in fruits, and was harmless to human health. This information is crucial for revealing the mechanisms of flavor damage caused by pesticides to strawberry and the repaired of nano­selenium, and broadens the researching and applying of nano­selenium in repairing the damage caused by pesticides.

Nano selenium repairs the fruit growth and flavor quality of tomato under the stress of penthiopyrad.

This study explored the repair effect of Selenium nanoparticles (Se-NPs) on tomato under the stress of Penthiopyrad (Pen), and expected to select out the optimal concentration and the application time of Se-NPs, to maximize the repair effect without causing phytotoxicity. The results showed that Pen induced severe oxidative stress on tomato and inhibited the growth and flavor quality of fruit. Compared with the control, the application of 1 mg/L Se-NPs at the immature green stage significantly improved the antioxidant capacity of tomato to reduce the MDA content. Besides, the plant hormones were synthesized normally, the contents of soluble sugars, volatile compounds and nutrients were increased, and the contents of organic acids were decreased in the 1 mg/L Se-NPs + Pen treatment group, which finally repaired the fruit flavor and quality. Therefore, the application of 1 mg/L Se-NPs and at the immature green stage represented a promising strategy for repairing the inhibitory effect of Pen on tomato fruit growth and flavor quality.