高山松与亲本种多种群在高海拔生境下的苗期适应性研究

为了检测高山松在高海拔生境下苗期适应性是否优于其亲本种（油松与云南松），阐明高山松相比于亲本种在其特有的高原生境下的苗期适应性特点，选择了代表高山松及其亲本种遗传变异的多个种群，在高海拔生境下对比分析了3个种13个苗期适应性性状指标。结果表明:大部分苗期适应性性状指标在种间及种内群体间差异显著，主要变异存在于种间及种内群体间，并且10月保存率、10月封顶率和二次生长率等性状方差分量大部分居于种间，种内变异稳定，是体现种间苗期适应性差异的重要指标。高山松大多数的适应性指标居于亲本种之间，其出苗率、保存率高于云南松，低于油松；封顶期晚于油松30 d左右，而云南松不封顶（2年生苗部分封顶）；在苗木生长表现上高山松超过亲本种，苗高、叶子红色和紫色比例也大于亲本种，且2年生苗木有二次生长；油松的封顶率和保存率为最高，云南松相应指标为最低值。这些结果表明高山松较油松有更长的生长期，比云南松有更强的适应性，是其在高海拔生境下发展成种的部分因素。 

Seedling adaptation of hybrid pine Pinus densata and its parental species in the high elevation habitat.

In order to test whether P. densata was more fit in its own high-elevation niche than its parental species ( P. tabuliformis and P. yunnanensis) and describe their adaptative characteristics in the seedling stage,we conducted a comparative analysis of the seedling adaptative characters in three species. The results showed that most of traits in the seedling stage were significantly different among species and populations,and large amount of variance was identified among species or among populations. The survival rate and the rate of bud-set in October were the best indicators of among-species divergence. The hybrid pine P. densata appeared to be intermediate between P. tabuliformis and P. yunnanensis in most of traits in the early stage. Compared with P. yunnanensis,P. densata had higher germination rate and survival rate,which were lower than P. tabuliformis,and the bud-set date was 30 days later than P. tabuliformis. The hybrid pine P. densata expressed transgression in four traits of seedling height,the ratios of the red seedlings,the purple seedlings and seedlings of secondary growth,which would reflect its unique adaptation in the high-elevation niche. P. tabuliformis was the highest in rates of bud-set andseedling survival. P. yunnanensis was lowest in seedling survival and only the two-year-old seedlings had signal of bud-set. P. densata had a longer growing season than P. tabuliformis,and stronger adaptation than P. yunnanensis. That could be one of the reasons about P. densata to become a hybrid in the highelvation habitat.