旱地油杉种子形态及散布特征研究

Studies on the Morphological and Dispersing Characters of the Seeds of Keteleeria xerophila

旱地油杉为松科濒危植物,仅分布在云南局部狭窄区域,数量稀少。为探讨旱地油杉的种子特征及传播特征与其致濒机制的关系,分析11个种子形态特征的变异及散布特征。结果表明:旱地油杉种子各形态特征变异顺序为种翅质量百分比>种子质量>种子总质量>种翅质量>种翅长/宽>种子宽>种翅长>种子长>种翅长百分比>种翅宽>种子总长;种子多个形态特征间关系表现为极显著正相关;种子滞空时间由种子各形态特征综合影响,与种子总质量、种子质量、种翅质量呈极显著负相关,R分别为-0.641、-0.637、-0.441,而与种翅质量百分比呈极显著正相关,R=0.577。旱地油杉的种子特征比较稳定,且适应远距离传播,但种群的自然更新能力低下,是导致其濒危的重要原因之一。

The species Keteleeria xerophila belonging to the family Pinaceae, is endangered and mostly distrib-uted in a very narrow area, Yunnan. At present, the populations of the species are rare. In order to discuss the rela-tionship between the endangering mechanisms and the characteristics of seed morphology and dispersal, the mor-phological variation and 11 dispersing characteristics of seeds were studied. The results showed that the order of seed variation was： the percentage of weight of seed wing﹥the weight of seed﹥the total weight of seed﹥the weight of seed wing﹥the ratio of length and width of seed wing﹥the width of seed﹥the length of seed wing﹥the length of seed﹥the percentage of length of seed wing﹥the width of seed wing﹥the total length of seed. The rela-tion between several morphological characters of seeds was extremely significant positive correlation. The hovering time was comprehensively influenced by the various characters of seeds and has an extremely significant negative correlation with the total weight of seed, the weight of seed and the weight of seed wing, the correlation coefficient was -0. 641,-0. 637 and-0. 441, respectively. The hovering time has an extremely significant positive correlation with the percentage of weight of seed wing, and the correlation coefficient was 0. 577. The seed morphology of K. xerophila was relatively stable and adapted to disperse for a long distance, but the natural regeneration ability of population was weak, which was one of the important reasons for being endangered.