【摘要】 由植原体侵染引起的甘薯丛枝病(sweet potato witches’-broom disease, SPWB)是影响我国甘薯(Ipomoea batatas)生产的重要病害，尤其在东南沿海甘薯产区。为实现灵敏、快速地检测甘薯丛枝植原体及其传播媒体内的植原体，本研究以甘薯丛枝病植原体转运蛋白基因secY为特异靶标，设计相应的Taq Man探针和引物，建立针对该病原的Taq Man qPCR检测方法，并使用所建立方法对采集的甘薯病样、虫媒和感染植原体的不同甘薯组织进行检测。结果表明，建立的Taq Man qPCR检测方法可对甘薯丛枝病植原体进行灵敏、快速精确检测，检测下限为1.71×10~1 copies/μL，可特异性区分苦楝丛枝植原体(Melia azedarach witches’broom phytoplasma, MWB)(16SrⅠ-B)、槟榔黄化植原体(Areca catechu yellowing phytoplasma, ACY)(16SrⅠ-B)、长春花小叶植原体(Catharanthus roseus periwinkle little leaf phytoplasma,PLL)(16SrⅠ-A)、甘薯薯瘟病菌(Ralstonia solanacearum)和甘薯黑腐病病菌(Dickeya dadantii)。利用该方法定量检测感染植原体的甘薯不同组织，结果表明，病原体含量范围为3.98×10~4～6.03×10~5 copies/μL，明确了植原体含量最高的组织为甘薯茎和茎基部。利用该检测方法对田间虫媒进行定量检测，明确东洋网室叶蝉(Orosius orientalis)为甘薯丛枝病植原体的传播媒介。综上，本研究建立的qPCR检测方法灵敏度、特异性和重复性好，能够实现对甘薯丛枝病植原体的快速检测，而且能够为从病原定量水平上对甘薯丛枝病病情分级提供参考。更多还原

【Abstract】 Phytoplasma-induced sweet potato infection is a significant disease that impacts sweet potato(Ipomoea batatas) production in China, particularly in southeastern coastal regions. This study developed specific primers and Taq Man probes based on the secY sequence of the sweet potato witches’-broom phytoplasma transporter protein gene for sensitive and rapid detection of the sweet potato witches’-broom phytoplasma and its presence in propagation media. A qPCR detection method was established using Taq Man,and was applied to test collected sweet potato samples, insect vectors, and various sweet potato tissues infected with phytoplasma. The results demonstrated that this Taq Man qPCR detection method could detect sweet potato witches’-broom phytoplasma sensitively, rapidly, and accurately, with a detection limit of 1.71×101 copies/μL. It could also specifically distinguish between Melia azedarach witches’-broom phytoplasma(16 Sr Ⅰ-B), Areca catechu yellowing phytoplasma(16 Sr Ⅰ-B), Catharanthus roseus periwinkle little leaf phytoplasma(16 SrⅠ-A), the causal agent of sweet potato bacterial wilt(Ralstonia solanacearum), and black rot pathogen of sweet potato(Dickeya dadantii). This method was used to quantitatively detect the pathogen content in different tissues of sweet potatoes infected with phytoplasma, revealing a pathogen content range of3.98×104～6.03×10~5 copies/μL, and identifying the sweet potato stems and the stem base as having the highest phytoplasma content. The insect vectors in the field were also quantitatively tested using this detection method, confirming Orosius orientalis as the transmission medium of sweet potato witches’-broom phytoplasma. In conclusion, the qPCR detection method developed in this study demonstrated good sensitivity, specificity, and repeatability. It not only enables rapid detection of sweet potato witches’-broom phytoplasma, but also provides a reference for grading the disease severity of sweet potato witches’-broom disease according to pathogen quantity.更多还原