桉树及其杂交种叶片形态的遗传变异特征

Genetic Variation Patterns in Leaf Morphology on Eucalypts and Their Hybrids

为了解桉树重要性状在杂交种亲本、子代间的遗传变异规律,以尾叶桉(Eucalyptus urophylla)为母本、粗皮桉(E. pellita)和细叶桉(E. tereticornis)为父本、8个全同胞杂交子代为材料,对亲本和子代的叶片形态性状进行了分析。结果表明,亲缘关系近的尾叶桉和粗皮桉的叶片性状大多无显著差异;但他们与亲缘关系远的细叶桉间的差异显著;尾粗桉与父母本间的性状无显著差异或仅与母本差异显著,属偏父本型;尾细桉与双亲间的多数性状都差异显著,且多偏向于母本。在树种内的家系间或个体间,叶片数量性状差异显著,而质量性状仅叶面革质厚度、叶面朝向差异显著;杂交种家系部分性状有超亲现象,且尾细桉家系超亲频率显著高于尾粗桉。叶长、叶长宽比、形状因子、叶色、叶面革质是区别叶片形态特征的决定性状。

To understand the genetic pattern on leaf traits variation between eucalypt hybrid progenies and their parents, the leaf morphological characters of female parent Eucalyptus urophylla, male parents E. pellita and E. tereticornis, and 8 hybrid progenies were studied. The results showed that there were not significant differences in leaf traits between two close relations of E. urophylla and E. pellita, whereas there were significant differences with distant relation E. tereticornis. The leaf traits of E. urophylla×E. pellita progenies had not significant differences with their parents, or there were more similar to male parent （E. pellita） than female （E. urophylla） parent. The leaf traits of E. urophylla×E. tereticornis progenies had significant differences with their parents, and had high similarity to female parents. Among individuals and families within species, the differences in leaf quantitative traits were significant, but qualitative traits showed significant differences only in leaf wax thickness and leaf orientation. Some leaf traits of hybrid progenies showed transgressive inheritance, the frequency of transgressive inheritance in E. urophylla×E. tereticornis were significantly higher than those in E. urophylla×E. pellita. Therefore, the length, ratio of length to width, shape factors, color and wax of leaf were determined properties in leaf morphological characteristics.