胡杨天然群体叶片不定芽分化性状分析

Character Analysis of Adventitious Buds Differentiation in Natural Population of Populus euphratica

再生是植物实现自我延存和后代繁衍的重要手段,离体叶片的不定芽分化是植物再生能力的重要体现。本研究揭示了新疆塔里木河流域胡杨群体内离体叶片不定芽分化的变异模式,分析了分化培养过程中间隔均匀的9个时间点动态性状的分布频率、变异系数和各时间点之间的表型相关系数,成功拟合了群体内87个个体的不定芽增殖曲线,对表征曲线的渐近值、增长速率和增速期持续时间三个参数在群体内作了比较和聚类分析。结果表明:(1)102个胡杨个体中,有87个分化出不定芽。(2)在第5～9个分化时间点之间,不定芽平均分化数量表现出高度相关性,相关系数介于0.89～1.00之间;第9个分化时间点表型在群体内呈极显著差异,变异系数为55.7%。(3)采用逻辑斯蒂生长曲线对群体内个体进行不定芽再生的动态拟合,决定系数r^2>0.95,渐近值、增长速率和增速期持续时间的变异系数分别为67.7%、55.4%和53.5%。(4)聚类分析显示,群体内87个个体的不定芽增殖曲线可被分为4类。上述结果揭示,胡杨天然群体内不定芽再生性状存在着丰富的变异模式,研究结果为胡杨天然群体的高解析度基因定位提供帮助,同时也为优良再生性状的种质资源利用与保护提供依据。

Regeneration is the crucial strategy for plants to achieve survive and reproduce, and the adventitious bud differentiation of detached leaves is an important embodiment of plant regeneration ability. The research revealed the variation model in natural population of Populus euphratica which was located in Tarim River Basin,Xinjiang. The distribution frequency, variation coefficient and phenotypic correlation coefficient of dynamic traits at 9 time points with uniform intervals during differentiation and culture were analyzed. The adventitious bud growth of 87 individuals in the population was successfully fitted. Propagation curve, the asymptotic value, growth rate and duration of growth period of the characterization curve were compared and clustered in the population.The results showed that 87 out of 102 genotypes could regenerate shoots. The average number of adventitious bud differentiation showed a high correlation between 5 and 9 differentiation time points, and the correlation coefficient was between 0.89 and 1.00. The ninth tim e point of differentiation was very significant, with a coefficient of variation of 55.7%. Logistic growth curve was used to simulate adventitious bud regeneration of individuals in the population. The coefficient of determination was r2>0.95, the coefficient of variation including asymptotic value,growth rate and length of linear growth duration were 66.7%, 55.4% and 53.5%, respectively. Cluster analysis showed that the adventitious bud growth curves of 87 individuals in the group could be divided into 4 categories.Above results revealed that there was abundant variation in the phenotype of bud regeneration in the narutal population, which could provide help for the high-resolution gene mapping in natural populations of Populus euphratica. Also, it could provide basis for the utilization and protection of germplasm resources with excellent regeneration characters.