白皮松种子休眠研究进展

Review on seed dormancy of Pinus bungeana Zucc.

种子休眠普遍存在于高等植物中,是植物历经长期的自然选择而保存下来的一种生物学特性。白皮松(Pinus bungeana Zucc.)是中国特有种,观赏价值高,以种子繁殖为主,但种子具有深休眠特性,给苗木繁育带来一定困难。分析关于白皮松种子休眠的研究结果认为,休眠原因主要包括:种子成熟时种胚的发育状况,内、外种皮和胚乳含有种类和含量不尽相同的萌发抑制物且脱落酸类在各部位均存在并有较强的抑制能力,种皮对种子萌发的机械阻力和透水性、透气性障碍以及内源激素在种子休眠中的作用。解除白皮松种子休眠的方法主要有低温层积处理、长时间流水冲洗、植物激素浸种、化学试剂和机械处理以及环境条件处理等。

Seed dormancy is pervasive in advanced plants,and is a biological characteristic that plants possess over long-term natural selection.Pinus bungeana Zucc.is an endemic species in China and has high ornamental value.It reproduces mainly through seeds;however,the seeds with deep dormancy cause difficulties in seedling breeding.In this study,the reasons for dormancy of P.bungeana seeds and the methods of dormancy breaking are summarized.The causes of dormancy mainly include the development of embryo in a mature seed;the presence of different kinds and amounts of germination inhibitors in the seed coat,paper layer,and endosperm;the presence of abscisic acid,which possesses strong inhibitory ability,in these three parts;mechanical resistance and permeability of the seed coat to germination;and endogenous hormones.The common methods of dormancy breaking are cold stratification,long-time flushing,soaking in plant hormones,chemical treatment,mechanical treatment and environmental condition treatment.