Chitosan and oligochitosan enhance ginger (Zingiber officinale Roscoe) resistance to rhizome rot caused by Fusarium oxysporum in storage

摘要

The ability of chitosan and oligochitosan to enhance ginger (Zingiber officinale) resistance to rhizome rot caused by Fusarium oxysporum in storage was investigated. Both chitosan and oligochitosan at 1 and 5 g/L significantly inhibited rhizome rot, with the best control at 5 g/L. Chitosan and oligochitosan applied at 5 g/L also reduced weight loss, measured as a decrease in fresh weight, but did not affect soluble solids content or titratable acidity of rhizomes. The two compounds applied at 5 g/L induced beta-1,3-glucanase and phenylalanine ammonia-lyase enzyme activity and the transcript levels of their coding genes, as well as the total phenolic compounds in rhizome tissues. Therefore, the ability of chitosan and oligochitosan to reduce rot in stored rhizomes may be associated with their ability to induce defense responses in ginger. These results have practical implications for the application of chitosan and oligochitosan to harvested ginger rhizomes to reduce postharvest losses. (C) 2016 Elsevier Ltd. All rights reserved.