‘紫王子’海棠半同胞家系花色特征分析及选优

Analysis and evaluation on flower color characteristics of the Malus 'Purple Prince' half-sib progenies

【目的】基于海棠基因库丰富的优良品种资源,初步探寻海棠花色遗传规律,并进行花色优株选评。【方法】对‘紫王子’海棠(Malus‘Purple Prince’)为母本的自由授粉子代半同胞家系进行花色变异分析。采用X-Rite色差计测定了44株子代半同胞家系大蕾期(S_1)、盛开期(S_2)、末花期(S_3)3个阶段的花色,分析了家系间的花色关系及色彩动态变化规律。【结果】S_1—S_3阶段,44株半同胞家系单株花色在3个维度方向(L~*、C~*、h~*)的变化均具有规律性:L~*值(亮度)呈上升趋势,且高亮度单株居多[S_1(45.45%)→S_2(77.27%)→S_3(84.09%)];C~*值呈持续下降趋势;h~*值呈上升趋势,即分布在红色区域的单株权重在开花进程中逐步下降。整个半同胞家系在遗传距离16和13处可分为3大色系(白色系、粉色系、红色系)和6个子色系,其中子代中白色系所占比重最大为68.2%。与疑似父本群体(97份种质)对比,半同胞家系群体花色稳定性更强,花色亮度更优,但色彩饱和度较低。在3大色系中,白色系从高亮度、高饱和性及色彩高稳性角度筛选出1株优株(株系号5033),粉色系从色彩高稳性和高饱和性角度筛选出1株优株(株系号5019),红色系从高亮度、高饱和性和色彩高稳性角度筛选出1株优株(株系号5032),优株花色观赏价值高于资源圃品种。【结论】通过自由授粉,‘紫王子’海棠子代群体的遗传基础被大大扩展,花色稳定性等的育种改良效果明显。

【Objective】In this project,experiments were based on the abundant resources in the crabapple germplasm bank. We obtained seeds through free pollination,then obtained half-sib progenies by sowing. The goal of this study was to explore the genetic law of flower color and select super individual with excellent color.【Method】We analyzed the color variation of half-sib progenies with’Purple Prince’crabapple( Malus’Purple Prince’) as their mother. To ensure the data measure was representative,the flower color parameters were recorded on the edge,middle,and base of 44half-sib progeny petals at big budding stage( S1),blooming stage( S2),and end flowering stage( S3). Color was measured using an X-Rite chromatic meter,and the flower color relationship among half-sib progenies and dynamic patterns of the flower color parameter distribution at different developmental stages were evaluated systematically. Comparisons were made with the suspected parental group and excellent plants in half-sib progenies were selected.【Result】From stage S1 to S3,the spatial distribution and change of color parameter sites in the dimension of L^*,C^*,and h^* changed regularly.L^* showed an increasing trend;the proportion of high brightness in the plant was large and the proportion of high brightness plants exhibited an increasing trend with the promotion of the flowering period( The value of L*in the 80-95 inter-val,S1( 45.45%) → S2( 77.27%) → S3( 84.09%)). C*( saturation) showed a continuous downward trend,and the proportion of low saturation plants exhibited an increasing trend with the promotion of the flowering period( The value of C^* in the 1-10 interval,S1( 50%) → S2( 77.27%) → S3( 84.09%)). h^* showed an increasing trend and the ratio of half-sib progenies in the red region( The value of h^* in the 0-20 interval) decreased during the flowering process. The half-sib progenies accounted for the largest proportion in the red region at the big budding stage( 43.18%),but the halfsib progenies accounted for the largest proportion in the yellow region( The value of h^* in the 80-110 interval) at the blooming stage and end flowering stage( 34. 09% and 38. 64%). Overall,the locus L^*,C^*,and h^* of half-sib progenies in S1 were more dispersed than the locus in S2 and S3. Thus,the color in S1 was most abundant. Cluster analysis was based on the flower parameters in S2 because ornamental crabapples had the highest value for flower viewing during the blooming stage. With a genetic distance of 16 and 13,all of the Malus’Purple Prince’half-sib progenies could be divided into three series( white series,pink series,and red series) and six color subseries. The white series occupied the largest proportion being 68.2% of the half-sib progenies. In the pink series,the subseries B1( pink red) were brighter than the subseries B2( pink white),and the flower color was well-distributed. In the red series,the brightness of the subseries C1( red) was greater than that of the subseries C2( purple red),but the value of a^* was lower. Compared with the possible paternal group( 97 ornamental crabapple cultivars),the half-sib progenies had stronger color stability and better color brightness,but the color chroma value was lower. In the three color series,based on high color brightness,high color chroma values,and strong color stability,we found one excellent plant in the white series( Number5033). This plant had white or very light pink flower color in S1,with high color brightness and high color stability.Based on high color stability and color chroma values,we found one excellent plant in the pink series( Number 5019).The flower color of this plant was stable,and the chroma was high. Based on high color brightness,high color chroma values,and strong color stability,we found one excellent plant in the red series( Number 5032). The plant had bright red flower color,and color stability during S2 to S3. The ornamental values of excellent plants were higher than that of the97 ornamental crabapple cultivars.【Conclusions】The genetic basis of half-sib progenies was expanded effectively by free pollination,but the genetic power of purple-red flower color was not strong,and it had an obvious effect on color stability and other traits.