巴西橡胶树抗白粉病室内鉴定模型的建立

Establishment of Indoor Identification Model of Rubber Tree(Heveae brasiliensis) against Powdery Mildew(Oidium heveae)

选取20份巴西橡胶树品系,将白粉病菌纯化后进行大田鉴定和3种温度下的室内鉴定,以评价各品系对白粉病的抗性并建立橡胶树抗白粉病室内鉴定模型。结果表明,20个橡胶树品系人工接种大田鉴定结果为高抗品系6个,抗病品系5个,感病品系3个,高感品系6个。在设置的22、25、28℃3个培养温度条件下,白粉病菌菌丝长度存在极显著差异,培养温度越高,病菌菌丝生长速度越快,菌丝长度越长。同时发现3种温度下白粉病菌菌丝长度比值不存在差异性,具有极其良好的稳定性。建立病情指数(y)与菌丝长度比值(x)的回归方程为:y=-62.072+80.909 54x,该方程可用于预测巴西橡胶树品系对白粉病的抗性等级。同时对橡胶树白粉病室内抗性评价的分级进行了修改,结合回归方程建立了巴西橡胶树抗白粉病室内鉴定模型,旨在为完善高效的巴西橡胶树抗白粉病鉴定评价体系提供基础和技术支持。

Total of 20 rubber tree（Heveae brasiliensis） clones were chosen,and inoculated by purified powdery mildew（Oidium heveae）.Then field identification and indoor identification in three kinds of temperature conditions were studied to evaluate the clone’s resistance level and establish the indoor identification model.The result showed that the resistance-susceptibility difference of rubber tree clones was distinct： high resistance（6 clones）,resistance（5 clones）,susceptibility（3 clones）,and high susceptibility（6 clones）.In the conditions of 22℃,25℃,28℃,there are significant differences in powdery mildew hypha length.The temperature turned higher,and the hypha growed faster and longer.In the meantime,powdery mildew hypha length ratio showed non-differential with strong stability at three temperatures.Accordingly,the regression equation was established of disease index（y） and hypha length ratio（x）：y=-62.072＋80.909 54 x,which can be used to predict the resistance levels of rubber tree to powdery mildew.And the evaluation classification table of rubber tree resistance level to powdery mildew indoors was modified,which constituted the indoor identification model of rubber tree resistance to powdery mildew with the regression equation,to provide a theoretical basis and technical support for a high-efficient evaluation system of rubber tree to powdery mildew.