笔竹(Pseudosasa viridula)花粉活力及柱头可授性研究

The Pollen Vitality and Stigma Receptivity ofPseudosasa viridula

通过研究不同条件下笔竹的花粉活力以及柱头可授性,为笔竹的有性繁育及杂交育种工作提供理论参考依据,并为竹类植物生殖生物学积累相关资料。采用I2-KI染色法、花粉离体培养基法测定笔竹花粉活力变化;采用联苯胺-过氧化氢法对不同开花阶段的柱头可授性进行测定。结果显示:笔竹新鲜花粉活性最强;1 d中笔竹花粉活性在3∶00 pm左右达到最高;不同浓度的蔗糖、硼酸配比对花粉萌发具有显著影响,笔竹花粉在10%蔗糖+0.01%硼酸浓度的培养基上培养3 h,萌发率最高;不同储藏条件对笔竹花粉萌发具有显著影响,而4℃湿藏条件下保存短时间内可延长花粉活力至120 h;柱头具可授性,可授期仅2~3 h,成熟期(散粉时期)柱头可授性最强。结论:笔竹花粉在10%蔗糖+0.01%硼酸的培养基内培养3 h萌发效果最好;1 d内尽量采集3∶00 pm左右的新鲜笔竹花粉对散粉时期的柱头进行人工授粉效果最好;新鲜花粉易失活,低温不干燥的储藏处理可以短时间内延长花粉寿命。

The pollen vitality and stigma receptivity of Pseudosasa viridula were investigated in order to provide a theoretical basis for sexual reproduction and hybrid breeding of bamboo plants.The pollen viability was determined by I2-KI staining and pollen culture medium in vitro,and the stigma receptivity was estimated by benzidine-H2O2 method.The results showed that the fresh pollen viability reached the highest at about 3∶00 pm,the ratio of the sucrose and the boric acid at different concentrations had a significant effect on the germination rate of the pollen,and it reached the highest in 10%sucrose+0.01%H3BO3 for 3 h.The storage conditions influenced the pollen germination dramatically,and the pollen vitality can be prolonged to 120 h under humid condition at 4℃.Stigmas had receptivity that could last 2 or 3 h,and the best time for pollination was the period of maturity.Thus,the pollen of Pseudosasa viridula is suitable to cultivate in the medium with 10%sucrose+0.01%H3BO3 for 3 h.The fresh pollens collecting at 3∶00 pm in a day are the best for the pollination of the mature stigmas.Fresh pollens are easily inactivated under natural condition,yet their activity can be prolonged for a short period of time under low temperature and humid storage conditions.