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China is a major apple producer, the output value accounts forty percent of fruits production. In our country, the picking period of apple almost in September or October, and then get into the refrigerator for storage, the longest store time can be the May or June of the next year for Fushi or Guoguang variety. During this period, apple is a living organism, still afterripening and aging, the number of microorganism on the apple is still changing over time, even enter the core through the pedicel and sepal, thus make the apple decay or mould, influence the production of apple. It is even worse that, the Aspergillus Clavalus and so on fungi which on the apple will produce patulin, which due to teratogenicity and carcinogenicity for embryoes of animals. This toxins stay stable in the major apple artifact—apple juice concentrate, which do harm to the health of people, and also restrict the export trade of apple juice concentrate.Microbial pesticide has a big market demand as one of the necessary capital goods of non-polluted agricultural product in pest control area. So far, we have got a good control efficiency by using microorganism on the crop disease of cucumber, capsicum, rice, wheat and corn. The technology of organism refreshment is the develop direction of modern refreshment technology, which has innocuity, innocence, non-pollution, and no adverse influence on flavor, has caused wide concern from production and study area.This study focus on the apple from ShaanXi, count the number of microorganism of epidermis, pedicel, sepal and core, and the chang of microorganism, fluocin and fungi number during picking time, 3, 6, 10 months after storage. And screening the bacteria from microorganism which can restrain the growth of Aspergillus Clavalus or other harm fungi by using culture-dish-confrontation and cup-plate method. Provide theoretical base for biotic-control of grain crops or orchard and the antisepticise and refreshment during storage time. Follow is the main results:1. Take sample during the picking time, 3, 6, 10months after storage from ShanXi, using NA、K’B、PG culture medium count the bacterial, fluocin and fungi from epidermis, pedicel, sepal and the core four parts. The results indicate that:①For four parts, sepal has the great number and sorts of microorganism, and then is the pedicel and epidermis, the number of core is most least. ②The numer of fungi is less than bacterial from four parts.③The main fungi on the surface of apple are Penicillum, Aspergillus, yeast, mucor, trichoderma and fusarium. Penicillum is the dominant fungi.④During the storage time, the number of microorganism is rise at first, and then decline, the change of core is small.2. Get four bacterials from microorganism by culture-dish-confrontation which can restrain the growth of Aspergillus Clavalus, these bacterias are:B1, B10, B22, B41. Through the preliminary identification of 4 fungal antagonists are Bacillus.3. Test the resistance of four bacterias to Aspergillus Clavalus and normal harm fungi which exist on crop plant by cup-plate method, The results indicate that: B22 has the strongest resistance among four bacterias, after 3 days of growth, the inhibition zone is 15mm. Then put B22 and spore of Aspergillus Clavalus together into apple’s wound, after 8 days of growth, the results indicate that: the rotten diameter of apple wound of CK is 25mm, and the experimental group is 15mm, obviously can restrain the decay of apple.4. There are some bacteria which can produce gases and volatile substance exist on the surface of apple, use these matters can suppress the growth of fungi, get two bacterias:G5, G10,the resistance rate are 71.7% and 32.6%.5. The best culture of Aspergillus Clavalus spore is apple juice, after 8 days of growth, the spore consistency is 7.5×10~6cfu/mL.
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