Studies On Test Guidline To New Varieties On Distinctness, Uniformity And Stability (DUS) And The Database To Existing Varieties Of Prunus Triloba L.

Prunus triloba is only distributed in China. It has a broad prospect for landscape application not only for their beauty but also for their resistance. However, the classification of its Prunus triloba varieties is in a state of confusion.Based on the systematic investigation of the existing species and varieties of flowering almond (Prunus triloba) in China in detail,palynology and molecular biology are used to analyze the relationship of variety resources of Prunus triloba and a new classification system of Chinese Prunus triloba is put forward and the DUS test guideline to new varieties and database to existing varieties of Prunus triloba are set up. The main results were as follows:1.Based on thorough investigation and research in main planted area of China, All of them are found in Northeast China(Haerbin,Changchun,Shenyang), Northwest China(Yinchuan,Lanzhou, Xining) and North China (Beijing, Taiyuan,Huhehaote). The morphological characters of the existing varieties were checked, corrected and named, The detailed investigation and classifying for flowering almond (Prunus triloba) according to the varieties of flowering almond in the areas above, 75 varieties are found.2.Pollen morphology of 75 Prunus triloba varieties in China is examined under scanning electron microscope.The normal pollen grains are varied from prolate to perprolate in shape.The number of apertures are 3 which belonged to the colp-orate type and the extine ornamentation can be divided into three groups:foveolate group,striate group and striate- foveolate group.The pollen characteristics of these varieties are differed in perforate diameters and extine ornamentatation,so they could provide scientific bases for variety and identification of Prunus triloba varieties.3.By using EcoRⅠ—MseⅠdigest and 5 primers,a suitable sliver-stainning AFLP system for Prunus triloba is developed.Clear DNA fingerprints are obtained,which mean success in DNA extraction,restriction-ligase reaction,double amplication,and the staining techniques.4. Based on above work and UPOV documents, the DUS testing guidelines to new varieties and database to existing varieties of Prunus triloba are set up.The objective of this study was to provide scientific bases for establishment of Prunus triloba varieties selection and breeding of eminent varieties,seeking and conservation of new varieties,and for protection and usage of genetic resources and their relationships in Prunus triloba and the Test Guidline to New Varieties on Distinctness, Uniformity and Stability(DUS)of Prunus triloba L. and the database to the known varieties.