油松花粉离体萌发及萌发特征研究

为了加强油松有性杂交，为种子园育种研究奠定基础，对油松花粉离体萌发的适宜条件及萌发特征进行了系统研究。结果表明，油松花粉在无蔗糖培养基中仍具一定萌发能力，蔗糖的添加可显著促进花粉萌发，但高浓度蔗糖可抑制花粉管的生长；油松花粉管易形成分枝，蔗糖浓度与分枝花粉频率呈正相关；硼酸的添加在培养初期可有效加速花粉萌发，但过高浓度的硼酸对花粉萌发具抑制作用；Ca2+对花粉萌发的影响较小，不同浓度Ca2+处理均可获得较高的萌发率；培养温度对花粉萌发的促进作用明显，但温度的持续升高将抑制花粉萌发。综合萌发率、花粉管生长及分枝花粉管频率，油松花粉萌发的最适液体培养基组成为：2.00%蔗糖+0.075%硼酸+0.005% Ca2+，26℃下光照培养，72 h时萌发率可达(96.10±0.47)%。

In vitro Pollen Germination and Characteristics on Pollen Tube of Pinus tabulaeformis Carr.

In order to further research on sexual hybridization and seed orchard breeding in Pinus tabulaeformis Carr., in vitro germination and characteristics of germination on pollen of P. tabulaeformls were studied. The results showed that in medium without sucrose, the pollen still had capability to germinate, although the germination rate was relatively low. The sucrose could promote pollen germination significantly, but high concentration of sucrose inhibited pollen tube growth. Tube branches could be formed during germination, and the frequency of branched pollen grains was positively correlated with sucrose concentration. At early of germination, boron acid was able to accelerate the pollen germination. However, excessively high concentration of the boron acid inhibited germination. A relatively high germination rate could be observed in all treatments with different concentrations of Ca2＋. Temperature promoted pollen germination, but the rate of germination decreased with temperature increase after 26℃. Integrating pollen germination rate, tube growth and frequency of branched pollen, the components of optimal liquid medium for P. tabulaeformis should be 2.00% sucrose＋0.075% boron acid＋0.005% Ca2＋. The germination rate could be reached （96.10±0.47）% after 72 h cultured at 26℃.