高能混合粒子场辐照小麦的突变效应分析

Mutagenic Effects of Mixed Particle Field Irradiation on Wheat

【目的】分析高能混合粒子场(CR)辐照冬小麦所产生的突变效应,并与60Co-γ射线处理相比较,研究其诱变效率。【方法】以0、145、195、284和560Gy剂量的CR和γ射线分别处理两个冬小麦品种ZY9和ZH7,室内发芽鉴定处理当代的损伤效应,田间筛选表型变异突变体并做考种分析。【结果】高能混合粒子场与γ射线处理对这两个小麦品种的生长抑制均存在明显的剂量效应,并且高能混合粒子场处理的损伤效应明显高于γ射线,ZH7的辐射敏感性大于ZY9,处理小麦的适宜剂量在200～300Gy之间。M2代群体中出现了包括株高、穗型、生育期等多种性状变异,在适宜或稍高剂量时可以引起明显高于γ射线处理的有益突变。CR诱变ZY9的总突变频率和有益突变频率分别为5.42%～11.68%和2.75%～7.29%,ZH7则分别达到10.35%～22.12%和6.62%～10.49%,均高于γ射线处理频率。【结论】高能混合粒子场处理小麦能够产生比γ射线更高的相对生物学效应,而且辐射敏感性较高的品种,经处理后其后代诱发有益突变的频率较高,获得优良变异的几率也相对较高。

【Objective】 Analyze the mutagenic effects and frequency of mixed particle field with high energy （CR） irradiation on winter wheat and compare with that of ^60Co-γ ray irradiation. 【Method】Air-dried seeds of winter wheat cultivars ZY9 and ZH7 were used and irradiated using CR and γ-rays at the dosages of 0, 145, 195, 284 and 560 Gy, respectively. The irradiated seeds were germinated in the laboratory, and mutants from M2 generation were screened and analyzed. 【Result】 There was an obvious linear dose-effect relationship on inhibiting plant growth of these two genotypes, the damage effect of CR was higher than that of gamma rays, and the cultivar ZH7 was more sensitive than ZY9. The optimal range of irradiation doses of CR for wheat was from 200 to 300 Gy. CR-induced phenotypic mutations in M2 populations included plant height, spike type and heading date, etc. The useful mutation frequency at the optimum or higher dosage was higher than that of gamma rays irradiation. The total mutation frequency and useful mutation frequency of CR treatment for ZY9 was 5.42%-11.68% and 2.75%-7.29%, for ZH7 was 10.35%-22.12% and 6.62%-10.49%, respectively, which were higher than that of gamma rays. 【Conclusion】These results revealed that the higher relative biological effect of CR treatment could be induced as compared with that of gamma rays. The more sensitive the variety was, the higher useful mutation frequency and the more probability of screening improved genotypes would be.