Studies On Test Guideline To New Varieties On Distinctness, Uniformity And Stability (DUS) And Database To Existing Varieties Of Lagerstroemia Indica

Crape myrtle (Lagerstroemia indica L.) is an important ornamental tree species of Lythraceae. It has a broad prospect for landscape application both in south and southwest of China. However, the existing varieties of L. indica are in a mess in China. Based on the investigation and research, numerical taxonomy and molecular biology are used to analyze the relationship of varieties of L.indica and the DUS testing guideline to new varieties and database to existing varieties of L.indaca are set up. The main results were as follows:1. The L.indica varieties are investigated in Beijing, Zhengzhou, Nanjing, Hangzhou, Wuhan, Chengdu, Chongqing and Yanling.The information of 53 L.indica varieties are collected in detail in which 30 varieties are new.2. Based on the morphology, 51 L.indica varieties and 2 species of Lagerstroemia are studied using the numerical taxonomy. The clustering result is in accord with earlier classification.3. By using 5 primers, a suitable silver-staining AFLP system for L.indica is developed. Clear and high-resolution DNA fingerprints were obtained, which meant success in DNA extraction, restriction-ligase reaction, double amplification and the staining techniques. The results of clustering analysis revealed the relationship among 37 L.indica varieties and two other species, which are generally consistent with the results from the study of numerical taxonomy.4. Based on above work and UPOV documents, the DUS testing guidelines to new varieties and database to existing varieties of L.indica are set up.The objective of this study is to provide scientific bases for seeking and conservation of new varieties, order existing varieties, establishment of L.indica varieties pool, protection new varieties.