甜柿巨大花粉萌发特征及辐射敏感性研究

以‘禅寺丸’（Diospyros kakiL.f)为试材，对巨大花粉萌发率，花粉管伸长，亲和性及辐射敏感性进行了研究。结果表明：（1）巨大花粉在培养基和柱头上正常萌发，不存在萌发及亲和性障碍；（2）巨大花粉萌发迟缓及低萌发率造成其与普通花粉受精竞争中处于劣势；（3）巨大花粉和普通花粉对^60Coγ-射线辐射敏感性有差异。巨大花粉的敏感性低于普通花粉，1200Gy为刺激巨大花粉萌发的适合剂量，同时可抑制普通花粉萌发，从而可相对提高巨大花粉的受精竞争力；（4）辐射延迟效应造成巨大花粉的萌发率在一定期间内有下降趋势。但自身的修复机制可部分恢复其生活力。

Study on Germinant Characteristic and Radiosensitivity of Giant Pollen in Nonastringent Persimmon

Studies were carried out on germination, pollen tube elongation, compatibility and radiosensitivity of giant pollen in 'Zenjimaru'persimmon(Diospyros kaki L.f.). The results showed that: (1) the normal germination of giant pollen in stigma and medium indicated that giant pollen is compatibility with female parent; (2) the delayer germinant process and lower germination rate of giant pollen caused weaker competition in mixed pollination than normal pollen, which is the real reason of low rate of acquired triploids in breeding practice; (3) giant and normal pollen have different radiosensitivity, and giant pollen were lower. 1200 Gy was the fitter dose of radiation to stimulate giant pollen germination, meantime to restrain some normal pollen. Therefore , the competition of normal pollen could be increased in stigma. (4) the effect of post radiation could declined germination rate of giant pollen, and the germination could increased partly as the result of damage repair.