巴西橡胶树自根幼态无性系耐低温分析

为比较橡胶树新型种植材料——自根幼态无性系与同源老态芽接无性系的耐低温能力，本研究将1蓬叶稳定的热研7-33-97老态芽接苗和自根幼态无性系苗5 ℃低温处理后，测定叶片的相对电导率、可溶性糖含量和游离脯氨酸含量等生理指标，并进行叶片受害调查。结果显示，自根幼态无性系叶片相对电导率低于老态芽接苗，可溶性糖含量和游离脯氨酸含量均高于老态芽接苗。此外，对5 ℃处理4 d后叶片受害情况调查发现，自根幼态无性系大部分叶片未受害，而老态芽接苗叶片几乎全部干枯或脱落。因此，室内低温模拟实验表明，自根幼态无性系在耐低温能力方面较老态芽接无性系更强，这为自根幼态无性系的生产应用提供了更广阔的前景。

Cold Tolerance Analysis of the Self-rooting Juvenile Clones of Hevea brasiliensis

To compare the cold resistance of the new planting material self-rooting juvenile clones and the traditional planting material budding trees of the rubber tree,the physiological indices of cold tolerance including the relative electric conductivity,the content of soluble sugar and free proline in leaves were measured and the phenotypes were observed in seedlings of Reyan 7-33-97 after 5 ℃ cold treatment.The data showed that the relative electric conductivity of the leaves in self-rooting juvenile clones was significantly lower than that in budding trees,and the content of soluble sugar and free proline in the leaves of the self-rooting juvenile clones were both higher than that of the budding trees.Moreover,after treatment for 4 days at 5 ℃,the leaves of budding trees had mostly senescent or falling,while most leaves of the self-rooting juvenile clones remained uninjured.The data demonstrated that the self-rooting juvenile clones were more cold-resistant than the traditional planting materials.This study would provide a convincing evidence for the large-scale cultivation of this new planting material in future.