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濒危植物鹅掌楸（Ｌｉｒｉｏｄｅｎｄｒｏｎｃｈｉｎｅｎｓｅ（Ｈｅｍｓｌ．）Ｓａｒｇ．）的花被片一般为９枚，对贵州松桃（Ｇ）、湖南龙山（Ｈ）和浙江龙王山（Ｚ）三地自然居群３年的观察发现，少数单株出现花被片数目变异，有１０、１１、１２枚花被片情况。与居群Ｇ和Ｈ相比较，居群Ｚ在单花花粉量，花粉大小和雌蕊数目等方面的变异较小，且无花被片数目变异。结实率与花部数目变异明显相关，变异较大的居群其结实率也高。居群间花粉平均大小与结实率有较好的正相关（ｒ＝０７６），并在居群间比较了结实率与花粉胚珠比（Ｐ／Ｏ）的关系（ｒ＝－０７４），发现Ｐ／Ｏ低的居群趋向于有较高的结实率，暗示资源配量限制了鹅掌楸的结实率。花部数量变异与结实率的关系表明潜在的遗传多样性对种子产量有明显影响。
The perianth segments of the endangered plant Liriodendronchinense (Hemsl.) Sarg. Were generally 9, with three natural populations of Songtao (G), Longshan (H) and Longwangshan (Z) The observation showed that the number of perianth pieces in a few plants varied with the number of 10,11,12 perianth pieces. Compared with the populations G and H, population Z had less variation in single flower pollen amount, pollen size and pistil number, with no variation in the number of perianth segments. Seed setting rate was significantly correlated with the number of floral units, and the population with large variation had high seed setting rate. There was a positive correlation between average pollen size and seed setting rate among populations (r = 076), and the relationship between seed setting rate and pollen ovule ratio (P / O) was compared between populations (r = -0.74 ). It was found that populations with low P / O tended to have higher seed setting rates, suggesting that resource allocation limited the seed setting rate of Liriodendron chinense. The relationship between the number of flowers and the seed setting rate showed that the potential genetic diversity had a significant effect on the seed yield.