Dryopteris crassirhizoma Dryocrassin ABBA for Postharvest Control of the Potato Dry Rot Pathogen Fusarium solani var. coeruleum

Dryopteris crassirhizoma dryocrassin ABBA treatment was tested for its effectiveness in controlling Fusarium solani var. coeruleum growth invitro and for prevention of postharvest dry rot of potato tubers and slices. Dryocrassin ABBA strongly inhibited mycelial growth, resulting in reductions in both mycelium dry weight and per cent spore germination of F.solani var. coeruleum at concentrations of 2.0, 0.5 and 0.1mg/ml. Scanning electron microscopy (SEM) observations showed that treatment induced abnormal, tightly twisted morphological changes in hyphae. Moreover, invivo experiments demonstrated that dryocrassin ABBA treatment at 2mg/ml effectively controlled dry rot of potato tubers inoculated with mycelial discs of F.solani var. coeruleum. After dryocrassin ABBA treatment, the content of soluble proteins, peroxidase (POD) and superoxide dismutase (SOD) activity increased, and malondialdehyde (MDA) content remained the stable situation. In addition, the expression level of plant lipid-transfer proteins (LTPs) genes - StLTPa1, StLTPa7, StLTPb1 and StLTPb3 - was upregulated. These results collectively demonstrate that dryocrassin ABBA can inhibit growth of Fusarium pathogens to induce disease resistance. On the other side, dryocrassin ABBA maybe induce potato defence responses.