南京椴种子休眠萌发特性研究

Study on Dormancy and Germination Characteristic of Tilia miqueliana

以去掉果皮的南京椴种子为材料,对其萌发特性进行了探讨,结果表明:南京椴离体胚在光照和黑暗条件下发芽率都达100%,说明南京椴的胚不存在休眠,且具有很强的萌发能力;去皮种子发芽率仅有14%;而去掉子叶周围胚乳(子叶露出)的种子,100%的种子下胚轴伸长,但是仅有59%的种子胚根突破胚乳而萌发出幼根;去除胚乳帽的种子发芽率为98%,但近50%的子叶始终未能展开;去掉部分胚乳,但子叶和胚根均未露出的种子发芽率为14%。这些结果说明胚乳和种皮是造成种子休眠的主要原因,尤其是胚乳和胚乳帽的作用更为关键。

The dormancy and germination characteristic was systematically studied in this thesis,taking seeds without capsule as material and the results showed that:The germination percentage of isolated seed embryo was 100%either in the light or dark culture,indicating that the seed embryo was not dormant and able to germinate;the germination percentage of decoated seed was 15%;when the endosperm surrounded cotyledon was removed,the hypocotyls of all the seed elongated but only 60%seed radicle could break through the endosperm;when the endosperm cap(the endosperm wrapping the radicle)was removed,98%seeds could germinate,but there were still 50%seed cotyledon couldn’t extend and only 14%seeds with wrapping cotyledon and radicle could germinate.These results indicated that the endosperm,especially the endosperm cap,was the barrier to germination.