在种子世界里，这使得它们很稀有，因为大多数开花植物的种子都很结实。

In the seed world, that makes them rare, because most seeds from flowering plants are quite robust.

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迄今种子园中开花株数和雄球花产量稳定增长，多数无性系植株平均着花量约在700个上下，但仍有约半数无性系的1/3植株尚未开雄球花。

There were about 700 male flowers per bearing tree for most of clones, but 46% of clones had 1/3 ramets bearing no male flower at all.

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