Genetic Diversity Evaluation And Cultivars Identification With Fingerprinting Based On AFLP In Five Sections Of The Genus Populus

A total of 44 clones/cultivars belonging to 18 species from 5 sections of the genus Populus were selected and used for AFLP, from Beijing, Shandong, Inner Mongolia, Xinjiang, Henan, Heilongjiang and so on. These included in 28 clones/cultivars of section Aigeiros, 5 of section Tacamahaca and section Leuce respectively, one of section Turanga and section Leucoides respectively, and 4 hybrids between section Aigeiros and section Tacamahaca or section Leuce. There were several parts of results as these as follows:1. AFLP analysis of five sections from the genus Populus for genetics diversityThe AFLP technique was employed to analyze these 44 samples using 64 primer combinations. A total of 588 bands, derived from 10 primer combinations between 44 samples, were scored. The differences among 44 samples at DNA level were determined by comparing the genetic similarity coefficients using STATISTICA software based on AFLP data. UPGMA cluster analysis showed, the 44 samples were divided into four major groups (I, II, III, and IV). Group I and Group II contained only one species, P. lasiocarpa Oliv. and P. euphratica, respectively. Group III comprises 5 species of section Leuce. Group IV comprises of 28 species/clones of section Aigeiros, 5 species of section Tacamahaca, and 4 hybrids between section Aigeiros and section Tacamahaca or section Leuce. Group IV was further divided into subgroups A, B, C and D. The high similarity coefficient ranging from 0.835 to 0.956 among them indicates that these 37 samples in group IV are very close to each other in spite of their different sections, different geographic origins, and different morphological traits.2. Conversion of AFLP marker into SCAR markerOne specific AFLP band M-CTC/E-AG374 of P. canadensis cv. 'Guariento' was cloned and sequenced. According to the spefific sequences of the cloned AFLP marker product, one specific primer set was designed and were tested on all the 44 Populus genotypes. The specific band, 246bp in length, amplified only in P.