小黑杨花粉离体萌发和细胞学分析

In Vitro Germination and Cytology Analysis of Populus simonii×P. nigra Pollen

采用花粉离体培养法,研究不同的液体培养基组分、温度、pH值对小黑杨花粉萌发的影响。结果表明:在单因子试验中,蔗糖、H3BO3和CaCl2在一定的浓度范围内对小黑杨花粉萌发及花粉管生长起促进作用,但超过一定浓度时则起抑制作用,温度和pH值也是如此。在正交试验中,蔗糖、H3BO3、CaCl2、温度和pH值对小黑杨花粉萌发均有极显著的影响,小黑杨花粉萌发最适的培养基为150g·L-1蔗糖+20mg·L-1H3BO3+40mg·L-1CaCl2,在21℃和pH6.0条件下,花粉的萌发率可以达到46.23%,花粉管生长状态良好。细胞学观察结果表明:小黑杨成熟花粉为2-细胞型,随着培养时间的延长,花粉萌发率逐渐提高,花粉管不断伸长。

The effects of liquid culture medium composition, temperature, pH value on Populus simonii×P.nigra pollen germination were investigated with in vitro culture. The results were as follows： First, sucrose,H3BO3 and CaCl2 could promote pollen germination and tube growth within a certain concentration range in single factorial experiments, but they would inhibit germination beyond the concentration range. Similar responses also held for temperature and pH value. Second, the effects of sucrose, H3BO3, CaCl2, temperature and pH value were extremely remarkable in orthogonal design experiment. The optimal culture medium was 150 g· L-1 sucrose ＋ 20 mg·L-1 H3BO3 ＋ 40 mg·L-1 CaCl2, and in the medium the rate of pollen germination was up to 46.23%under the conditions of 21 ℃ and pH 6.0, with healthy pollen tube. Third, cytological observations exhibited P. simonii×P. nigra mature pollen was a bicellular pollen and pollen germination rate gradually increased and tube was growing with culture time.