| Apple is an important fruit worldwide. Apple anthracnose caused by Colletotrichum spp. has been a great problem for apple production in China. Especially,Colletotrichum gloeosporioides (C.g) was found predominantly over cultivation area during the infection periods and developed severe rots on both green and ripe fruits that caused major yield losses. However,little research was conducted on biological characteristics of the pathogen,and pathphysiology of postharvest apple anthracnose.In the present work a research on the biological characteristics of the pathogen,and pathphysiology of postharvest apple anthracnose were conducted. Also the effects of the fungicides to control this disease were studied. 1. Biological Charateristics on Apple Anthrancnose (Colletotrichum gloeosporioides)The effect of the temperature,humidity and acidity alkalinity on Colletitrichum gloeosporiodes hyphal growth rate,conidia germination and germ tube elongation were conducted. Also the effects of temperature and acidity alkalinity on hyphal growth in liquid culture medium were studied.The results reported as follows:the growth temperature range from 15 to 35 the hyphal could survived,and it ranged from 20 to 30 the hyphal growed better ,it was optimum at 28. Low temperature such as 0,inhibited hyphal growth and conidia germination only,but was not the deadly line. Incubated at 40 ,hyphal could survive 5 days,that is,the deadly time was 5 days,but conidia could not germinate until 11 days. It was beneficial for conidia germination and germ tube elongation from 20 to 30,it was optimum at 25 ,germ tube was longest than that of others at 30 . Colletotrichum gloeosporioides incubated by liquid culture medium,the hyphal dry weight was the heaviest at 30 than that of other temperature. When the surrounding relative humidity was less than 80%,hyphal could not grow normally ,but when the relative humidity was more than 80%,the difference of hyphal growth rate has not significance. Conidia germination requested strict humidity condition,itgerminated only in free water or in water film. There was a wild scope of acidity alkalinity in hyphal growth and conidia germination,the pH scope ranged from 3 to 11 and from 2 to 11 respectively,pH4 was optimum. Incubated in liquid culture medium,when acidity alkalinity range from 4 to 10,the difference of hyphal growth has not significance. Conidia could germination in acidity and alkalinity condition,but acid was better.The incidence and development of disease were determined by pathogen,host,enviroment and interaction of each other. Those factors including pathogen capacity,the way and period of infection,resistance of host,temperature and humidity of enviroment and so on influenced disease development. Disease incidence and severity both increased when initial pathogen capacity increased during apple storage. Disease incidence by sting inoculation was the most among the sting,spray and smear inoculation.lt showed that wound would increase succession of infection. During the storage the developing currilinear of apple postharvest anthracnose appeared unsymmetric "Surve under the certain condition.Using gompertz model simulated the currilinear of disease development,simulation fitness was significance.2. Physiological Pathology of Postharvest apple Anthracnose caused by Colletotrich urn gloeosporioidesLesion expansion,latent period and infection ratio etc. were correlated with some biogenic enzyme such as peroxidase (POD) polyphenoloxidase (PPO) phenylalanine ammonia-lyase(PAL) and polygalaturonase(PG),chtinase,P -1,3-glucanase. Especially PPO,Chtinase and P -1,3-glucanase were significantly correlated with resistance to host. The activities of PPO,POD,PAL,PG,PE,Chitinase and 3 -1,3-glucanase after inoculation anthracnose pathogen (Colletotrichum gloeosporioides) were studied. The results showed that metabolic defense induced by the attacking pathogen including the activity of PPO,POD,PAL,PG,PE,and Chtinase,& -1,3-glucanase.That is the activity of these enzyme markedly increased...
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