大别山五针松种子特性及促进种子萌发的研究

大别山五针松是中国特有珍稀树种,其野生状态种子萌发率极低,自然更新困难。对大别山五针松种子进行测量统计并与其他常见松树种子进行对比,以了解其种子特性;采取破壳处理探索种皮是否对种子萌发具有阻碍作用;利用赤霉素（GA3）、吲哚乙酸（IAA）、2,4-二氯苯氧乙酸（2,4-D）3种植物生长调节剂进行处理,设置正交试验探索植物生长调节剂、浓度、处理时间的不同水平对大别山五针松种子萌发的影响。结果表明：（1）大别山五针松种子较大,千粒重为313.19 g;含仁率较低,为36.33%;种皮较厚,为0.60 mm,种皮比例为54.34%。（2）由于种皮太厚,未进行破壳处理的大别山五针松种子很难吸水萌发,种皮的机械阻碍是限制种子萌发的因素之一。（3）GA3、IAA、2,4-D都能促进种子的萌发,但三者之间没有显著差异。综合考虑各因素,促进大别山五针松种子萌发的最佳处理方法为：破壳处理,采用0.2 mg/L的GA3浸种12 h。

Pinus dabeshanensis Seed Characteristics and the Promotion of Seed Germination

Pinus dabeshanensis Cheng et Law is a rare species endemic to China with low seed germination rate and difficult natural regeneration in the wild.In order to comprehend its characteristics,seeds of Pinus dabeshanensis were measured and statistically analyzed and compare with other common pine species in this paper.Its episperm was removed to inquire into its inhibitory effect on germination.And 3 different plant growth regulators,gibberellin（GA3）,indole acetic acid（IAA）,2,4-dichlorophenoxyacetic acid（2,4-D） were used to set the orthogonal experiment to explore the role of hormone species,concentration and treatment time in the seed germination of Pinus dabeshanensis.The results showed that：（1） Pinus dabeshanensis seeds was large with the thousand seed weight was 313.19 g;the percentage of kernel was 36.33%.It had a thick episperm of about 0.60 mm and ratio of which was 54.33%.（2） Due to the mechanical barrier effect of episperm,the seeds without removing them were hard to germinate,making it one of the limiting factors of seed germination.（3） GA3,IAA,2,4-D could both promote the germination of seeds with no significant difference among them.Synthetically considering,the optimal treatment to promote seed germination of Pinus dabeshanensis were：removing episperms,immersing seeds in 0.2 mg/L of GA3 for 12 h.