BIOLOGICAL CHARACTERS AND PHYLOGENY OF POLYPLOID SUGAR BEET (Beta Vulgaris L.) VARIETIES AND PARENTS

In this study, genetic variation of Iifteen polyploid varieties and eleven main parents (Beta vulgaris L.) were revealed by using phylogeny and RAPD markers. Nineteen morphological characters were investigated in different periods. A variant analysis was made for nine out of nineteen traits, which were analyzed through correlation and classification. Four main economic traits-root yield, sugar content, sugar yield and leaf spot resistance were identified. RAPD was used to study general DNA of twenty-six accessions in eight random 10-primers and two double-primers. At the same time, we constructed the dendrogram of genetic relationship of 26 accessions and evaluated genetic diversity. The main results are as follows: I .The morphological identification results showed that leaf color, petiole color, and growth vigor had no obvious differences, and other sixteen characters had different genetic variances. Particularly, seedling weight of one hundred, leaf length, leaf width, petiole length. petiole width, leaf number, leaf rosette height, leaf rosette diameter, seed weight of one thousand and hypocotyl color had significant differences. In the same time, using the method of hierarchical cluster processed cluster analysis. 2.Through identification of four economic traits of 26 accessions, we found that root yield; sugar Content and sugar yield of Tianyan varieties were higher than others. However, the leaf spot resistance had no significant variances. We also knew that the economic traits of genetic monogerm polyploid varieties had no better expressed. 3. A RAPD analysis method was developed for sugarbeet genomic DNA. The amplified reactions were performed in the Thermal Cycler PTC-200,whose program was: 1mm initial denaturing at 94C followed by 4ocycles of l5sec denaturing at 95C, 45sec annealing at 37C, I min,extension at 72 C ;at last,5min for extension at 72 . 4.Fifteen sugarbeet polypoid variety and eleven parents were analyzed by RAPD with 8 random primers and two double-primers. Fifty-eight amplified fragments were detected. The polymorphic fragments were 42 bands, and polymorphic frequencies were 72.4%.5.As results from cluster analysis based on phylogeny and RAPD data, it was concluded: The polyploid sugarbeet varieties have abundant genetic diversity. But genetic background was vulnerable among sugarbeet parents. 6.The results from cluster analysis are consistent with pedigree pattern. It showed that both phylogeny and RAPD markers are fit for the research of genetic relationship.