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本文分析了贮藏温度和介质水分对苏铁种子后熟的影响及种子的脱水耐性。结果表明,种子是透水的,新成熟的苏铁种子的胚很小(3.45 mm),胚的长度/种子长度之比值(E:S)约是0.089。在适宜的条件下,胚能继续发育和生长,其子叶胚在萌发时的临界长度约16.38 mm。由此得知,苏铁种子是形态休眠的。另外,苏铁种子对干燥脱水十分敏感,是顽拗性的,一旦严重失水就会劣变,甚至死亡。在冷层积(4°C)时,75%的介质含水量比50%和25%的介质含水量更有利于胚的后熟。而且,在室温下,长时间的干藏和水藏都容易导致种子死亡。所以,保持湿润是保存苏铁种子的关键。此外,施用GA3溶液(500 mg·L~(-1))处理可以加速冷层积种子的胚的发育,缩短解除休眠的时间。
The effects of storage temperature and medium moisture on the ripening of cycads and the dehydration tolerance of seeds were analyzed. The results showed that the seeds were water-permeable, the embryos of the young mature cycads were small (3.45 mm) and the ratio of embryo length / seed length (E: S) was about 0.089. Under appropriate conditions, the embryo can continue to develop and grow, and the critical length of its cotyledons during germination is about 16.38 mm. From this we know that the seeds of cycads are morphologically dormant. In addition, the seeds of cycads are very sensitive to dehydration and dehydration, which is recalcitrant. Once severe dehydration, they will deteriorate and even die. At cold stratification (4 ° C), 75% media moisture is more conducive to embryo ripening than 50% and 25% media moisture. Moreover, at room temperature, prolonged dry storage and water storage can easily lead to the death of the seeds. Therefore, keeping moist is the key to conserve the cycads. In addition, GA3 solution (500 mg · L -1) accelerated the embryo development of cold stratified seeds and shortened the time of dormancy release.