鹅掌楸苗期动态生命表

报道了鹅掌楸在苗圃播种后的出苗率和幼苗存活率,根据定期观察数据编制了苗期动态生命表。结果表明,4个种源的出苗率都很低(1.64%～3.05%),比其各自的饱满种子率低得多;天然种源的出苗率高于栽培的种源,但前者的出苗数占饱满种子数的比例却低于后者。至一个生长季以后,幼苗存活率仅占出苗数的16%～27%,而黄山种源与庐山种源的交配后代则高达60%,明显地高于其亲本和其它种源。种子大小对于出苗率和幼苗存活率没有直接影响。最后讨论了遗传因素和生存环境对幼苗存活的影响,并认为种子和幼苗适合度低是鹅掌楸致濒的重要原因之一。

Dynamic seedling life table of Liriodendron chinense

The emergence and survival rates of Liriodendron chinense in a seedling nursery were investigated, and dynamic life table was complied based on the periodical observation data. The result shows that the emergence rates of four kinds of provenance were quite low (1.64～3.05%), much lower than those of their full-seeds. The emergence rate of natural provenance was higher than that of cultivated provenance, but the rate of seedlings to full-seeds for the natural provenance was lower than that for the cultivated one. After a growth season, the rate of seedling survival to emergence was 16～27%, whereas that of the later generation of mating by Huangshan and Lusha provenance was 60%, significantly higher than that of their parents and other provenance. The size of seeds had no direct effect on seedling emergence and survival. The effect of genetic and environmental factors on seedling survival was also discussed. It is suggested that the low fitness of seeds and seedlings is one of the important factors causing the species being endangered.