美国梾木(Cornus spp.)花粉活力及萌发特性

为了了解美国梾木花粉活力及萌发特性,采用扫描电镜技术对13个美国梾木无性系花粉形态进行观测与方差分析,并采用荧光显微技术和TTC染色法对无性系2号花粉萌发特性及花粉活力进行观察。结果显示:(1)不同无性系间花粉大小差异不显著,但外壁纹饰差异较大,极面沟距的变异系数最高且遗传最为稳定。(2)花序开花率为75%时花粉活力最高,整花4℃条件下短期保存花粉活力较高。(3)授粉后,多数花粉可在柱头上正常萌发,72 h后花粉管即可进入子房。研究认为,花粉外壁及极面沟距可作为鉴定美国梾木无性系的形态指标,美国梾木花粉活力及萌发特性是抗逆及丰产杂交组合的重要保证。

Viability and Germination Characteristics of Cornus spp. Pollen Grain

In order to breed high-yield species,pollen grains of 13 Cornus spp. Wanyer clones were observed using scanning electron microscope and analyzed using analysis of variance. Pollen germination and pollen viability of clone 2 were viewed using fluorescence microscope and TTC staining method. The results showed that: (1)The size of pollen grains among different clones were similar,but the exine sculpture were variable. The variation coefficient of the furrow spacing in polar view was high and the inheritance was the most stable. (2)The pollen viability was highest when 75% of the inflorescence flowered. Whole flowers stored at 4°C for one month had higher pollen viability. (3)Most of the pollen grains could germinate on stigma,and their pollen tubes could enter the ovary in 72 h after pollination. In conclusion,exine sculpture and the furrow spacing could be used as morphological indexes to identify different clones. Pollen germination and pollen viability were important to breeding program.