^(12)C^(6+)离子束辐照对小麦种子萌发、幼苗生长及存活的影响

Effects of ^(12)C^(6+) ion beams irradiation on germination, plant growth and survival of wheat seeds

采用12C6+离子束对小麦(Triticum aestivum L)种子进行不同剂量(0、10、20、30、60、120、150和200 Gy)辐照处理,考察种子萌发率、幼苗根长及株高、有丝分裂活动及存活率等生物学特性。结果表明:试验剂量范围内,大多数种子能够正常萌发;低剂量(10 Gy和20 Gy)辐照对幼苗生长具有促进作用,而高剂量辐照则表现出明显的抑制作用;根的生长与分生组织细胞有丝分裂指数密切相关,低剂量时有丝分裂指数略有增加,而高剂量则相反,分裂细胞被选择性阻滞在中期和后期。存活率曲线呈"抛物线"状,半致死剂量(LD50)为55Gy。

Wheat （Triticum aestivum L） seeds were irradiated with different doses of 12C6＋ ion beams. Several biological endpoints including seeds germination rate, seedling root length and plant height, mitotic activities and survival rate were investigated. The results showed that in all dose range, most irradiated seeds were able to germi- nate normally. Low doses radiation （10-20 Gy） had a stimulation effect on seedling growth, while high doses radia- tion played an inhibition role. Especially root growth was strongly related to mitotic index. MI increased in low doses and decreased in high doses, and the mitotic cells were arrested in metaphase and anaphase. The survival curve showed that the “parabola” trend and the median lethal dose （LDso） was 55 Gy.