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坡垒(Hopea hainanensis Merr.et Chun.)、青皮(Valica astrotricha Han-ce)种子不能长期干藏,经作者试验研究,原因在于经过干藏种子含水率迅速下降,坡垒种胚及子叶颜色变暗,韧性降低变脆,无光泽。根尖细胞亚显微结构明显变化,当含水量从34.0％降至20.3％以下时细胞质空泡化,细胞核的结构正常,然后液泡膜破裂,核内结构变得模糊,直至质壁分离,核膜和核仁的界限不分明,染色体均质化,呈黑色一团,各种细胞内的物质已大量消失,剩下胞壁或仅含某些分解残物。青皮种子根尖细胞当水量下降至23.1％时许多细胞处于解体。作者认为:坡垒、青皮种子之所以因干燥而降低活力,除有人解释为蛋白质变性成为不可逆转的凝胶以外,而且在失水过程中,其细胞的亚显微结构受到不同程度的破坏。坡垒、青皮植物的种实在成熟后无休眠现象,仍需保持很高的含水量(40—50％),只能湿藏。
The seeds of Hopea hainanensis Merr.et Chun. And Valium astrotricha Han-ce can not be stored for a long time. The experimental study is based on the fact that the moisture content of dried seeds is rapidly decreased, Dark, toughness to reduce brittle, dull. The ultrastructure of root tip cells changed obviously. When the water content decreased from 34.0% to 20.3%, the cytoplasm became vacuolized and the structure of the nucleus was normal. Then the vacuole ruptured and the structure of the nucleus became blurred until the plasm wall was separated. Membrane and nucleolus boundaries are not clear, the chromosome homogenization, a black mass, a variety of intracellular material has largely disappeared, leaving only the cell wall or only some of the decomposition of the residue. Many cells are in disintegration when the amount of water drops to 23.1%. The author thinks that the reason why the seedling of hillock and peel is desiccated by drying is that unless one explains that protein denaturation becomes an irreversible gel, the submicroscopic structure of the cell is destroyed to some extent during dehydration. Hill base, the plant species in the skin without sleep after maturity, still need to maintain high water content (40-50%), only wet storage.