合江方竹种子大小变异对萌发及幼苗生长的影响

Effect of Seed Size Variation of Chimonobambusa hejiangensis on Seed Germination and Seedling Growth

根据合江方竹单粒种子的重量分布频率,将种子主要分为3个数量级并开展育苗试验,研究不同大小、形状的合江方竹种子萌发率及对幼苗生长的影响。结果表明,合江方竹种子的单粒重集中在0.12~0.2 g之间,种子大小对其萌发率影响不大,六叶期的死亡株数明显大于三叶期。种子大小与幼苗植株地径、根长、茎高等生长指标呈极显著正相关,大粒种子使幼苗健壮成长的几率更高,而种子的长/宽比值对幼苗建植无明显影响。合江方竹种子的大小差异性状对三叶期幼苗的茎高影响较大,而在六叶期时这种影响明显减弱。因此,为了保持合江方竹幼苗较高的成活率及生长优势,育苗时应优先选择大粒种子,并且当幼苗生长至三叶期后,及时给予施肥等抚育措施补充养分,从而降低幼苗死亡率。

According to the weight distribution frequency of single seed of Chimonobambusa hejiangensis,the seeds were mainly divided into 3 order of magnitudes and seedling experiments were carried out to study the effects of seeds of different size and shape on its germination rate and seedling growth.The results showed that the weight of single seed for C.hejiangensis was concentrated from 0.1 g to 0.2 g.The seeds of different sizes of C.hejiangensis had little effect on its germination rate,and the number of dead plants at the six-leaf stage was significantly higher than that in the three-leaf stage.There was a very significant positive correlation between seed sizes and growth indexes like,root length and height at seedling stage.Large seeds had higher probability of robust growth of seedlings,but the ratio of seed length to width had no significant effect on seedling establishment.The difference in seed size of C.hejiangensis had a great effect on the diameter and height of seedlings in the three-leaf stage,but weakened obviously in the six-leaf stage.Therefore,in order to maintain the high survival rate and growth advantage of C.hejiangensis,large seeds should be given priority,and when the seedlings grow to the three-leaf stage,we should be nurtured and replenished in time to reduce seedling mortality.