AFLP-based Genetic Diversity Analysis Of Oats

Oat belongs to genus Avena L. in Gramieae. It is an annual crop with high feed and food value. In this study, genetic diversity of 34 covered oat varieties and 8 naked oat varieties from China, Australia, Canada , Europe and other countries was studied using AFLP makers to provide basis for oat genetics and breeding research. The results showed as follows:1. The factors affecting AFLP analysis including primer selection, digestion and ligation of DNA, amplified conditions and detection ways were optimized. An optimization system of AFLP markers was established: 800ng/μL oat DNA was digested with 10U EcoRⅠand 4U MseⅠat 37℃for 7h and then 65℃for 4h, ligation mixture was kept at 16℃for 12h;pre-selective amplification was set up with 1μL restriction-ligation sample DNA, 0.6μL 10μmol/L EcoRⅠand MseⅠprimers, 2μL10×buffer and 2μL dNTPS, ddH2O was added up to 20μL. In 20μL selective amplification, 5μL diluted (20×) DNA pre-selective amplification product, 0.8μL 50ng/μL EcoRⅠand Mse I selective primers. Under this optimization system, clear, steady and higher polymorphic oat AFLP bands were obtained.2. Five primer pairs were selected from 30 primer pairs for AFLP analysis, 268 informative AFLP markers were generated and scored as binary data, which showed a polymorphic band ratio of 69.0%. In Nei's index calculation, the average genetic diversity was 0.1664, and Shannon diversity index was 0.2206. All cultivars Pairwise similarity coefficient varied from 0.4881 to 0.9881, with 0.0120-0.7172 genetic distance.3. The fingerprinting data were further analyzed using UPGMA Cluster methods in the software NTSYSpc version 2.1, which clustered the 42 varieties into six main distinct groups, in which genetic similarity coefficient was 0.748.4. Thirty four covered oat varieties and 8 naked oat varieties were divided into two groups in which genetic similarity coefficient was 0.59, this result was in accordance with traditional classification.5. There was some distinct difference between domestic oat germplasms and introduced ones. Narrow genetic background was found within Chinese varieties; while genetic diversity of Canadian oats was much higher.6. Higher genetic similarity coefficient among all naked oats further improved their same origins.