60Co-γ射线辐射对翠冠和玉露香梨枝条的生物损伤效应

为探明⁶⁰Co-γ射线辐射对梨枝条的生物损伤效应,以翠冠和玉露香梨的一年生休眠期枝条为试验材料,以不同剂量(0、20、30、40、50 Gy)的⁶⁰Co-γ射线对枝条进行辐射处理,研究不同辐射剂量对梨枝条接穗嫁接成活率及生物损伤效应的影响。结果表明,随着辐射剂量的增加,梨枝条嫁接成活率逐渐降低,梨叶片出现畸形,枝条出现二叉枝和多叉枝。对不同辐射处理的枝条萌发叶片的相对叶绿素(SPAD)含量进行主成分(PCA)和偏最小二乘判别分析(PLSS-DA),发现所有辐射处理均对翠冠梨产生了较大的影响,其中20、40 Gy 2个处理对玉露香梨影响最大。此外,经过⁶⁰Co-γ诱变处理的玉露香梨叶片易受炭疽病病菌侵害。本研究结果为今后利用⁶⁰Co-γ射线辐射诱变技术提高梨遗传多样性、创造新的种质材料、加快选育优良新品种提供了理论依据。

The Biological Damage Effects of 60Co-γ Ray Radiation on Cuiguan and Yuluxiang Pear Branches

To study the biological damage effects of ⁶⁰Co-γ rays irradiation on pear branch, one-year dormant shoots of Cuiguan and Yuluxiang pear were used as materials and treated with different ⁶⁰Co-γ radiation doses (0, 20, 30, 40 and 50 Gy). The results showed that the survival rates of grafted branches of the two pear cultivars were both gradually decreased with the increment of radiation dose. The radiation treatments resulted in malformed leaves, and two or three bifurcated branches. The leaves SPAD (soil and plant analyzer development) values were analyzed by the PCA (principal component analysis) and PLSS-DA (partial least squares-discriminant analysis), we found that ⁶⁰Co-γ radiations with each dose all made great difference on the Cuiguan pear branches, whereas the Yuluxiang pear branches were only affected by 20 Gy and 40 Gy irradiation. In addition, the germinated leaves of radiated Yuluxiang pear branches were liable to be infected by anthrax (Colletotrichum gloeosporioides). These results provide a theoretical basis for increasing genetic variation, creating new germplasm materials and speeding up breeding new varieties in pear.