楸树不同单株花性状变异分析

Flower Characters Variation of Different Individuals of Catalpa bungei

楸树是我国中部地区重要的珍贵阔叶用材和著名的园林观赏树种,已有2 600多年的栽培历史。研究其花性状多样性与变异性旨在揭示花表型性状在楸树种内存在的巨大变异,为新花色育种和优良观花新品种的选育及新品种的鉴定和保护提供理论依据。以1985~1990年收集的优良单株和杂种F1共27株为材料,测定了花性状中的2个质量性状和7个数量性状,并采用方差分析、聚类分析等方法进行统计分析。①27株的开花物候期差异可达5 d,花大小、花序长短和单株花量均有较大差异,并且由于叶柄长度和花枝长度的差异导致不同单株表现出显花和隐花特征。②楸树为二强雄蕊,分为雄性可育和败育,调查的27株中有12株为雄性可育,且花粉量差异较大。③花冠檐部5裂,上唇3瓣,下唇2瓣,上唇瓣长度大于下唇瓣。27株的花枝长度、花序长度、单花枝花数、花上唇瓣长度、花下唇瓣长度和花冠直径均存在极显著差异,单株间的变幅分别为10.7~16.4 cm、5.6~9.6cm、2~13朵、3.8~5.2 cm、3.0~4.3 cm、3.9~5.4 cm,表型变异系数分别为12.8%、12.5%、36.7%、7.5%、9.1%和9.2%。④16株间花色L^*值(亮度值)、a^*值(红绿值)、b^*值(黄蓝值)、C^*值(彩度)和h值(色相)均存在极显著差异,a^*值、b^*值以及彩度C^*值的表型变异系数分别为35.1%、52.5%和29.8%;以L^*、a^*和b^*值度量花色,通过聚类分析将16株聚为3类,红色系、粉红色系和白色系。楸树27株的花枝长度、花序长度、花大小差异极显著,16株的花色也具有明显的差别,依据L^*、a^*和b^*值进行聚类分析,当欧氏距离为15时可将16株聚为3类:红色系、粉红色系和白色系。

Catalpa bungei is important hardwood timber and ornamental tree in the central China. It has been cultivated more than 2 600 years. Study on the diversity of flower traits reveals the huge intraspecific phenotype variation of flower in C. bungei,and would provide useful information for identification and protection of new variety and theoretical basis for flower color and excellent ornamental cultivars in Chinese C. bungei breeding project. Superior individual and hybrids F1 were collected in 1985-1990. A total of 27 individuals,and two qualitative and 7 quantitative traits of flower were analyzed using variance analysis and cluster analysis methods.①The difference of flowering phenology of 27 individuals was up to 5 d. The flower size,inflorescence length,number of flower per plant of the 27 individuals showed significant differences. In addition,different individuals showed a characteristics of explicit flower and implicit flower because of difference of the length of petiole and the length of flowering branch. ②C. bungei is didynamous stamen,which divided into male fertile and sterile.Twelve of the 27 individuals that in survey were male fertile. There was a significant difference in the amount of pollen. ③The flower is trilobation with five lips,which has two-sectional upper lip,three-sectional lower lip,and the length of upper lip flap is larger than the lower lip. The length of flower branch, length of inflorescence,amount of flower of single flower branch,length of upper lip of flower,length of lower lip of flower and corolla diameter of 27 individuals have significant differences. The value changes were 10.7-16.4 cm,5.6-9.6 cm,2-13 flower,3.8-5.2 cm,3.0-4.3 cm and 3.9-5.4 cm,respectively. The coefficients of variation were 12.8%,12.5%,36.7%,7.5%,9.1% and 9.2%,respectively. ④The L^*value( the value of brightness or black and white),a^*value( red and green value),b^*value( yellow and blue value),C^*value( chroma),and h value( hue) between the 16 individuals were significantly different. The coefficients of variation of the a^*value,b^*value and chroma C^*value were 35.1%,52.5% and 29.8%,respectively;measuring color with L^*,a^*and b^*value,the 16 individuals were clustered into 3 categories,red,pink and white by cluster analysis. The length of flower branch,length of inflorescence,and size of flower of the 27 individuals of C. bungei have significant differences. The color of the 16 individuals also have obvious variation. According to the L^*,a^*and b^*value by cluster analysis,the 16 individuals were clustered into 3 groups,red,pink and white when the value of Euclidean distance is 15.