| Kiwifruit is mainly distributed in south of Qinling and east of Transversal Mountain in China. Qinling mountainous area which has the rich wild germplasm resource is also the eugenics area of kiwifruit. The kiwifruit is a kind of perennial, dioecism plant, with the nature of common inter-species hybridization. A series of transitional forms usually generated after different variety's hybridizing.The complicated chromosome ploidy in addition can cause confusion in taxonomy and hereditary property among some species and mutations. Our research aimed at these questions and get some results through the investigation of Kiwifruit germplasm resources, the appraisal as well as the RAPD analysis, established the Qinling wild kiwifruit resources database of biology characteristic, the fruit nutritional quality and the molecular genetic map, we have also screened some fine kiwifruit germplasm resources.All these results provides the basis for the kiwifruit heredity relationship and the kiwifruit germplasm resources' appraisal and the new variety's protection. The main results were as follows:1. Through the investigation of wild kiwifruit resources in Qinling mountain and the analysis of biology characteristic as well as the fruit quality of the main cultivated variety, this paper first established a database of biological characteristics, fruit nutrition and quality of the wild kiwifruit resources in Qinling mountain, and then screened out a wild variety named 99-9 line whose mature period is slightly later than cultivated variety Wuzhi NO.2. According to clustering analysis of wild kiwifruit,we found that 99-8, 99-9,99-10,99-13,99-16 and 99-17 can be used as breeding materials of medium or precocious varieties. Meanwhile, 7 lines of cultivars that have bigger average fruit weight than Hayward including 99-5,99-9,99-11, 99-13,99-16, 99-20,99-21,99-24 and 99-23 were obtained, 3 lines of varieties that have larger Vc content than Wuzhi NO.2 containing 99-8, 99-13 and 99-23 were gained.3 lines of varieties that contain larger content of solid/acid than Wuzhi NO.2 such as 99-8, 99-9 and 99-14 were obtained, 3 lines of character comprehensively better cultivars, 99-9 and 99-13 were gained. Among all lines above, 99-9 has more potential whether in view of the early mature character, fruit quality or resistance. Therefore the research of wild kiwifruit resources which have prominent economic characters will play a huge role in current breeding practice. 2. Three methods for extraction of genomic DNA i.e. classical CTAB method,improved CTAB method and benzyl chloride method are practical and efficient.The result shows that improved CTAB method is the best method,because it obtains high-quality genomic DNA with less degradation and impurity.A number of factors affected the results of RAPD were studied such as annealing temperature,cycle numbers,quantity of template DNA and kinds and concentration of Taq DNA polymerase enzyme etc.The optimized RAPD analysis system of the genus in kiwifruit was established . Several clear bands with better polymorphism,stability and repeatability could be obtained.3. Random amplified polymorphic DNA (RAPD) was applied to detect genetic diversity of the samples of 24 wild kiwifruits collected from Qinling mountain areas and other 22 varieties. 16 RAPD primers produced 235 bands, of which 227 bands were polymorphic. The polymorphic bands accounted for 96.29% of the total bands. UPGMA (Un-weighted Pair Group Mathematics Average) clustering analysis displayed the genetic relation among the varieties, 23 wild kiwifruits are A. deliciosa var. deliciosa,same as Hayward.1 wild kiwifruit is A. chinensis Planch.4. After the combined analysis to the biological characteristics, fruit quality and the genetic distance of the wild kiwifruit resources in Qinling Mountain areas, the 99-13 was demonstrated to belong to A. chinensis .The other 23 wild kiwifruits were classified in the A. deliciosa var. deliciosa because of the nearer genetic distance with Yate, the Qinmei, Xuguan and Xuxiang. The wild cultivars 99-23, 99-24 have many common biological characteristics(mature period,et al) with Yate, in addition, we got the result that both of 99-23 and 99-24 have very close genetic distance with Yate. So we can infer that 99-23, 99-24 and the Yate was of the same variety. From the result of the UPGMA, we may safely conclude that there is a close genetic distance among the wild 99-23, 99-24 and Mute. 99-9 belongs to A. deliciosa var. deliciosa.
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