关键词: 人参, 腐皮镰刀菌, 细胞壁降解酶, 生理生化指标

Abstract: In order to clarify the relationship between the resistance to root rot of Panax ginseng and the activities of antioxidant and secondary metabolism related enzymes,  fresh P.ginseng was used as the material to conduct artificial infection with Fusarium solani to study the changes of physiological and biochemical indexes of P.ginseng after infection treatment. The experimental results show that the activities of cell wall degrading enzymes in the bacterial invasion group are basically higher than those of the blank control group,  and the activity of polygalacturonase (PG) is the highest. The pectinases that play the main roles are PG and polymethylgalacturonase (PMG). The activities of superoxide dismutase (SOD) and catalase (CAT) in the bacterial invasion group reach the peak at 14 d,  and the activity of peroxidase (POD) in the bacterial invasion group reach the peak at 28 d,  indicating that P.ginseng increased the activity of plant defense enzymes in order to resist bacterial invasion. The activities of phenylalanine ammonia-lyase (PAL) and polyphenol oxidase (PPO) in the bacterial invasion group are higher than those in the control group,  indicating that the invasion of pathogenic bacteria may induce the increase of PPO and PAL activities. The mass molar concentration of malondialdehyde (MDA)  in the bacterial invasion group is lower than that in the control group,  indicating that P.ginseng can inhibit the invasion of pathogenic bacteria. The mass fraction of soluble sugar  in the pathogen invasion group is always higher than that in the control group,  which may be a self-protective reaction of P.ginseng against pathogen invasion.

Key words: Panax ginseng,  , Fusarium solani,  , cell wall degrading enzyme,  , physiological and biochemical index