Jujube witches' broom is a devastating disease of Ziziphusjujube that occurs in various jujube regions of China. Nucleic acid extracted from midribs of samples collected from three jujube varieties ("Suanzao", "L...Jujube witches' broom is a devastating disease of Ziziphusjujube that occurs in various jujube regions of China. Nucleic acid extracted from midribs of samples collected from three jujube varieties ("Suanzao", "Lajiaozao" and "Langzao") from symptomatic and asymptomatic shoots were tested by random amplified polymorphic DNA analyses. Using 13 different 10 and 11-bp random primers the amplification of jujube DNA was achieved from all the samples; AMI4 primer provided amplification of specific DNA fragments of about 400 bp, only from samples collected from symptomatic plants. No genetic variations in these varieties were identified using the other 11 arbitrary primers; only with primer AL07 it was possible to differentiate "Langzao" from the other two varieties tested. All the experiments were repeated 2 times and the results were consistent. Compared with PCR analyses with phytoplasma-specific primers, RAPD techniques resulted to be an alternative rapid and sensitive method for detecting jujube phytoplasmas presence in different jujube varieties.展开更多
Jujube Witches’ Broom (JWB), caused by phytoplasma, is the most serious and destructive disease of Chinese Jujube. The distribution and year_round concentration variation of JWB phytoplasma were studied under fluores...Jujube Witches’ Broom (JWB), caused by phytoplasma, is the most serious and destructive disease of Chinese Jujube. The distribution and year_round concentration variation of JWB phytoplasma were studied under fluorescence microscope using DAPI. The results showed that phytoplasma might exist in the sieve tubes of all organs, phytoplasma contents varied with organs, sides of organs and growing seasons, phytoplasma usually existed in the roots of the same direction with diseased branches. The uneven_distribution could be observed much often in lightly diseased trees than in seriously diseased one. In roots, the content of phytoplasma was highest in May, relatively low in June, July and August, and lowest in December to March. In branches, the content of phytoplasma increased gradually with the rising of the temperature after bud sprouting in April and May, then increased dramatically and reached peak in July and August, thereafter decreased in autumn. From December to February, there was still a large amount of phytoplasma in diseased branches. The content of phytoplasma in branches kept higher than in roots throughout a year.展开更多
【目的】目前发现,北京枣园中的凹缘菱纹叶蝉Hishimonus sellatus(Uhler)和片突菱纹叶蝉Hishimonus lamellatus Cai混同发生。已知凹缘菱纹叶蝉可以传播枣疯病,而片突菱纹叶蝉是否携带枣疯病植原体尚待证明。正确鉴别区分枣园中菱纹叶...【目的】目前发现,北京枣园中的凹缘菱纹叶蝉Hishimonus sellatus(Uhler)和片突菱纹叶蝉Hishimonus lamellatus Cai混同发生。已知凹缘菱纹叶蝉可以传播枣疯病,而片突菱纹叶蝉是否携带枣疯病植原体尚待证明。正确鉴别区分枣园中菱纹叶蝉的种类并测定其体内感染枣疯病植原体情况有助于阐明田间枣疯病的流行规律,从而提出有效的预防枣疯病及其媒介昆虫措施显得十分重要。传统形态学鉴定两种菱纹叶蝉种类的方法局限于雄性成虫外生殖器,本研究目的在于建立一种快速的分子生物学方法,在区分枣园中两种枣菱纹叶蝉的同时,可检测虫体内的枣疯病植原体。【方法】以凹缘菱纹叶蝉和片突菱纹叶蝉的COI基因以及枣疯病植原体的16S r DNA为扩增目标,分别设计引物,建立一种包含3对引物的多重PCR体系。测试该多重PCR体系对叶蝉总DNA的灵敏度、准确性,以及当两种叶蝉DNA同时存在时的辨别能力和对枣疯病植原体16S r DNA的灵敏度。【结果】该多重PCR可以准确区分凹缘菱纹叶蝉和片突菱纹叶蝉,并对虫体内枣疯病植原体实现检测,其对昆虫总DNA的灵敏度达到0.012 ng,对枣疯病植原体16S r DNA模板的灵敏度达到900拷贝。【结论】该方法极大方便了对枣菱纹叶蝉的田间种群发生动态及虫体中枣疯病植原体感染的监测。展开更多
文摘Jujube witches' broom is a devastating disease of Ziziphusjujube that occurs in various jujube regions of China. Nucleic acid extracted from midribs of samples collected from three jujube varieties ("Suanzao", "Lajiaozao" and "Langzao") from symptomatic and asymptomatic shoots were tested by random amplified polymorphic DNA analyses. Using 13 different 10 and 11-bp random primers the amplification of jujube DNA was achieved from all the samples; AMI4 primer provided amplification of specific DNA fragments of about 400 bp, only from samples collected from symptomatic plants. No genetic variations in these varieties were identified using the other 11 arbitrary primers; only with primer AL07 it was possible to differentiate "Langzao" from the other two varieties tested. All the experiments were repeated 2 times and the results were consistent. Compared with PCR analyses with phytoplasma-specific primers, RAPD techniques resulted to be an alternative rapid and sensitive method for detecting jujube phytoplasmas presence in different jujube varieties.
文摘Jujube Witches’ Broom (JWB), caused by phytoplasma, is the most serious and destructive disease of Chinese Jujube. The distribution and year_round concentration variation of JWB phytoplasma were studied under fluorescence microscope using DAPI. The results showed that phytoplasma might exist in the sieve tubes of all organs, phytoplasma contents varied with organs, sides of organs and growing seasons, phytoplasma usually existed in the roots of the same direction with diseased branches. The uneven_distribution could be observed much often in lightly diseased trees than in seriously diseased one. In roots, the content of phytoplasma was highest in May, relatively low in June, July and August, and lowest in December to March. In branches, the content of phytoplasma increased gradually with the rising of the temperature after bud sprouting in April and May, then increased dramatically and reached peak in July and August, thereafter decreased in autumn. From December to February, there was still a large amount of phytoplasma in diseased branches. The content of phytoplasma in branches kept higher than in roots throughout a year.
文摘【目的】目前发现,北京枣园中的凹缘菱纹叶蝉Hishimonus sellatus(Uhler)和片突菱纹叶蝉Hishimonus lamellatus Cai混同发生。已知凹缘菱纹叶蝉可以传播枣疯病,而片突菱纹叶蝉是否携带枣疯病植原体尚待证明。正确鉴别区分枣园中菱纹叶蝉的种类并测定其体内感染枣疯病植原体情况有助于阐明田间枣疯病的流行规律,从而提出有效的预防枣疯病及其媒介昆虫措施显得十分重要。传统形态学鉴定两种菱纹叶蝉种类的方法局限于雄性成虫外生殖器,本研究目的在于建立一种快速的分子生物学方法,在区分枣园中两种枣菱纹叶蝉的同时,可检测虫体内的枣疯病植原体。【方法】以凹缘菱纹叶蝉和片突菱纹叶蝉的COI基因以及枣疯病植原体的16S r DNA为扩增目标,分别设计引物,建立一种包含3对引物的多重PCR体系。测试该多重PCR体系对叶蝉总DNA的灵敏度、准确性,以及当两种叶蝉DNA同时存在时的辨别能力和对枣疯病植原体16S r DNA的灵敏度。【结果】该多重PCR可以准确区分凹缘菱纹叶蝉和片突菱纹叶蝉,并对虫体内枣疯病植原体实现检测,其对昆虫总DNA的灵敏度达到0.012 ng,对枣疯病植原体16S r DNA模板的灵敏度达到900拷贝。【结论】该方法极大方便了对枣菱纹叶蝉的田间种群发生动态及虫体中枣疯病植原体感染的监测。