| Experiment was carried out on main grapes varities.In this article,the main pathogens induing rot on postharvestgrapes were detected,Elicitor was extracted from cell wall of Botrytis cinerea and this elicitor was used to induce resistance on postharvestgrapes,the mechanism of induce resistance was preliminary study. It was showed that the main pathogens of post-harvest grapes rot disease were Botrytis cinerea,Aspergillus niger,Penicillium spp., Rhizopus stoloniter,Alternaria spp. and Phomopsis sp. through isolating, purifing, pathogenicity determination, identification and ways of infection on grape varities of "Manai", "Ko","Red Globe"and "Meiguixiang".Among these pathogens, Aspergillus niger and Rhizopus stolonite were the chief pathogens during post-harvest transportation and marketing because they cause rot disease during high temperature, yet Botrytis cinerea and Alternaria spp. were the major pathogens during transportation and storage under 5℃.Rhizopus stoloniter and Aspergillus niger only can infect when wound exist,others can infect whenever wound exist or not. At the same time,the main pathogens were different on different grape cultivars or different location on same varity. From the result of extracting elicitor from cell wall of Botrytis cinerea, we can found that the essential components were saccharides and protein, that more than 25.6% of Botrytis cinerea was neutral saccharide ,the other 18.45% was protein. The result revealed that the treatment of removing protein by 20% trichloroaceticacid addition can warrant the loss of neutral saccharide less than 9%,while percent of removing protein more over 85%. After induce resistance on post-harvest grapes using this elicitor, the result showed that the treatment of elicitor induced resistance of post-harvest grapes fruit and the disease incidence was reduced.After storage 90 days in 0℃,the contrast disease incidence and disease index were 58.86% and 38.77%,but the disease incidencs of elicitor 25μg/mL,75μg/mL and 125μg/mL were 20.77%, 16.98% and 10.23% in turn, the disease indexs were 30.94%,16.55% and 8.71%.On stalk of post-harvest grapes, the resistance was induced by elicitor in concentration range, elicitor 75μg/mL reduced disease on stalk, the disease incidence and disease index were 42.23% and 10.55% after storage 90 days,the difference was significant comparing with other treatment, elicitor 125μg/mL also reduced disease incidence and disease index,they were 55.78% and 13.71%, after treatment with elicitor 25μg/mL, the disease incidence and disease index was not significant compare with control. It was displayed that POD,PPO and PAL activity in post-harvest grapes peel and stalk were enhanced with elicitor treatment. After treatment with 125μg/mL,POD,PPO and PAL activity in peel change was obvious.The PAL activity change in stalk is higher than others with 75ug/mL treatment.The PPO activity in stalk descending is slowly than others after treating with 125μg/mL,The POD activity were not significant between 75ug/mL and 125ug/mL,their pump appeared interval 10 days. The result of mass of relative resistance indicated that the content of phenol and lignin in post-harvest grapes were higher than control. In peel,the pump of phenol elicitor 125μg/mL, 75μg/mL and 25μg/mL were 923.45U,923.89U and 897.66U in turn,Yet,the control was 656.67U,the result in peel was perfecter than in stalk.The content of lignin in Elicitor 25ug/mL,75ug/mL,125ug/mL sequentially increased 12.28%,26.18% and 30.65% in peel,while in stalk, they were increased 8.43%,12.29%,11.24% in turn. There were no siginificantly difference in content of total sugar,titratable acid ,total soluble solid,penetration of pericellular membrane and chlorophyl between elicitor treatment and control during storage.The result expressed that the value of edible and appearance were not affected. There were no siginificantly difference in growth and spore germination of pathogens.From this result ,we believe that elicitor have no inhibition on pathogens.
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