Studies On Genetic Diversity Of The Phenotype Characteristics In Danlias

Taking good Dahlia cultivars as the tested materials, study the morphological genetic diversity morphological traits. Analyzed the stability of the sectional cultivars and classified the selected cultivars. The computer information technology combined with digital images was used to describe the color of leaf and petal. Offer new evidence for saving the genetic recourse, and breed excellent cultivars and improving. Describe the morphological traits scientifically and accurately.1. Taking4Dahlia populations as testing materials, analyze genetic diversity of12morphological traits. The results showed that there was extremely rich variation on phenotypic traits among and among individuals within populations of dahlia. The difference of12morphological traits were extremely significantly different among populations and4morphological traits were significantly different; Flower diameter and big pattern of genetic diversity index of the highest; The differentiation indices of average12phenotypic characteristics was70.36%. The variation from among dahlia population was the main source of variation for phenotypic characteristics.2. Selected9elite dahlia cultivars, measured7phenotype traits in3years and analyzed their stability. The results indicated that effects of genotype on leaf length, petiole length and pedicel length were extremely significantly different, but there were no significant difference in effects of environment. Other phenotypic traits have significant difference in both effects of genotype and effects of environment. Effects of genotype on leaf length, leaf width, petiole length, flower diameter, pedicel length and stem diameter were greater than environment except that effects of environment on plant height were greater than genotype.3.Analyze the stability by AMMI model in the basis of variance, The result showed that for leaf width the most stable cultivars were’Bodascious’and’Pam Howden’. The varieties with better stable petiole length included’Bodascious’and’Papageno’. The cultivars with better stable pedicel length included’Hy Enid’and’Pennsgift’. Environment was much more appropriate for leaf width, petiole length and pedicel length in2009than that in2010and 2011.4.20morphological traits of52dahlia cultivars were analyzed by cluster analysis. The results showed that flower diameter was served as the first classification criteria and size of leaves, size of petal and amount of petal were the second one.20characteristics were divided into several parts though R-cluster. Leaf length and leaf width, felloe and inner petal length, felloe and inner petal width were all closely related, but most of characteristics were independent.5. In principal component analyses (PCA),20characters were integrated into7principal components (PC) and their accumulative contributor ratio amounted to74.713%, and13major discriminating characteristics were selected according to the relativity between7PC and characters. They were leaf length, leaf width, felloe petal length, felloe petal width, inner petal length, inner flower width, color of petiole, flower diameter, petal number, initial blooming stage of single flowering, color of flower bud, color of pedicel, and florescence of single flowering.6. Colour describing is agreed with the results of cluster analysis, checking veracity and feasibility of color analysis.