中文摘要：

在前一研究结果的基础上，选用8个对UV—B辐射耐受性不同的小麦品种（4个耐性品种和4个敏感品种），进一步对其进行RAPD分析。结果表明，8个小麦品种间存在着明显的遗传多态性。聚类分析显示，在遗传距离为0．35的水平上，可将它们明显区分出耐性和敏感两大类，这与其生长响应指数（RI）的判定结果基本一致。4个耐性品种共同具有1500bp（OPA-12）的特征谱带，这一分子标记可能与小麦耐UV—B辐射相关，有待进一步研究。

英文摘要：

The decline in stratospheric ozone concentration has been confirmed by satellite measurements. Mathematical models predict a further increase in solar UV-B irradiation in further years. Effects of UV-B on plants have been the subjects of considerable research. An examination of more than 200 plant species reveals that roughly 20% are sensitive, 50% are mildly sensitive or tolerant and 30% arc completely insensitive to UV-B radiation. In the past time, we reported that there were intraspecific differences in growth and grain yield response of 10 wheat cuhivars to UV-B radiation, according to response index （RI）, 4 sensitive cuhivars and 4 tolerant cuhivars have been determined. Plant species and even genotypes within species can differ greatly in their responses to UV-B. Based on the preceding research results, 8 wheat cuhivars that responded differently to enhanced UV-B radiation, including 4 tolerant cuhivars and 4 sensitive cuhivars, were further made RAPD analysis. The results showed that there was obvious genetic polymorphism among 8 wheat cuhivars. They were divided into two types at the level of 0.35 of genetic distance, that is, 4 cuhivars were tolerant and other 4 were sensitive to enhanced UV-B radiation. This classification was consistent with the result of RI. As a common DNA band of 4 tolerant cuhivars, 1 500bp （OPA-12） was correlated with UV-B-resistibility of wheat, which needed further study.