[目的]探究水稻白叶枯病菌是否存在存活但不可培养状态(viable but non-culturable,VBNC),将有助于更好地了解水稻白叶枯病的病害循环,为有效防治水稻白叶枯病提供理论基础。[方法]对分离采集自田间、保存在室温和4℃下14年的水稻白叶...[目的]探究水稻白叶枯病菌是否存在存活但不可培养状态(viable but non-culturable,VBNC),将有助于更好地了解水稻白叶枯病的病害循环,为有效防治水稻白叶枯病提供理论基础。[方法]对分离采集自田间、保存在室温和4℃下14年的水稻白叶枯病叶,采用划线稀释分离法进行病原菌的平板分离,探索不同温度处理下病叶中白叶枯病菌的可培养情况。将带利福平抗性的白叶枯病菌PXO99^(A)菌株剪叶接种感病水稻品种‘深两优871’,病叶剪成小段分别置于4、28和37℃下保存,每隔30 d取病叶小段,通过平板分离进行病原菌含量的测定。利用染色全细胞染料Microlight^(TM) Green JJ98 and JJ99以及染死细胞染料碘化丙啶(PI)对喷菌液中细胞的存活程度进行测定。[结果]采集自田间、保存在室温和4℃下的病叶都有明显的喷菌现象;只有从4℃保存(甚至保存4年)的样品上可以分离到病原菌,而保存在室温的样品上都不能分离到白叶枯病菌。从人工接种的保存在3个温度下的病叶上分离的病原菌,随着保存时间的增加,可培养的PXO99^(A)菌量呈现下降趋势,其中37℃保存60 d后未分离到病原菌。荧光染色结果显示,保存60 d后,4、28和37℃条件下保存的样本中活细胞的比例分别为52.52%、32.17%和24.02%。以上结果说明,37℃病叶中的病原菌部分进入了VBNC状态。[结论]高温诱导了水稻白叶枯病样中的病原菌进入了VBNC状态。这为研究水稻白叶枯病菌的侵染生物学特征和制定有效的防治策略提供了科学依据。展开更多
DNA-binding fluorochromes are often used for vital staining of plant cell nuclei. However, it is not always sure whether the cells after staining still remain in living state. We chose several criteria to estimate the...DNA-binding fluorochromes are often used for vital staining of plant cell nuclei. However, it is not always sure whether the cells after staining still remain in living state. We chose several criteria to estimate the validity of real vital staining for sexual cell nuclei. These were: the cytoplasmic streaming in pollen tubes whose nuclei were stained, the simultaneous visualization of fluo-rochromatic reaction and nucleus staining in isolated generative cells, and the capability of isolated, prestained generative or sperm cells to fuse with other protoplasts. The results confirmed that 4',6-diamidino-2-phenylindole (DAPI), Hoechst 33258 and mithramycin could be used as real vital stains, though their efficiency varied from case to case; among them DAPI showed best effect. The fluorescent vital staining technique offered a useful means fori-dentification and selection of heterokaryons in gametoplast manipulation studies.展开更多
文摘[目的]探究水稻白叶枯病菌是否存在存活但不可培养状态(viable but non-culturable,VBNC),将有助于更好地了解水稻白叶枯病的病害循环,为有效防治水稻白叶枯病提供理论基础。[方法]对分离采集自田间、保存在室温和4℃下14年的水稻白叶枯病叶,采用划线稀释分离法进行病原菌的平板分离,探索不同温度处理下病叶中白叶枯病菌的可培养情况。将带利福平抗性的白叶枯病菌PXO99^(A)菌株剪叶接种感病水稻品种‘深两优871’,病叶剪成小段分别置于4、28和37℃下保存,每隔30 d取病叶小段,通过平板分离进行病原菌含量的测定。利用染色全细胞染料Microlight^(TM) Green JJ98 and JJ99以及染死细胞染料碘化丙啶(PI)对喷菌液中细胞的存活程度进行测定。[结果]采集自田间、保存在室温和4℃下的病叶都有明显的喷菌现象;只有从4℃保存(甚至保存4年)的样品上可以分离到病原菌,而保存在室温的样品上都不能分离到白叶枯病菌。从人工接种的保存在3个温度下的病叶上分离的病原菌,随着保存时间的增加,可培养的PXO99^(A)菌量呈现下降趋势,其中37℃保存60 d后未分离到病原菌。荧光染色结果显示,保存60 d后,4、28和37℃条件下保存的样本中活细胞的比例分别为52.52%、32.17%和24.02%。以上结果说明,37℃病叶中的病原菌部分进入了VBNC状态。[结论]高温诱导了水稻白叶枯病样中的病原菌进入了VBNC状态。这为研究水稻白叶枯病菌的侵染生物学特征和制定有效的防治策略提供了科学依据。
文摘DNA-binding fluorochromes are often used for vital staining of plant cell nuclei. However, it is not always sure whether the cells after staining still remain in living state. We chose several criteria to estimate the validity of real vital staining for sexual cell nuclei. These were: the cytoplasmic streaming in pollen tubes whose nuclei were stained, the simultaneous visualization of fluo-rochromatic reaction and nucleus staining in isolated generative cells, and the capability of isolated, prestained generative or sperm cells to fuse with other protoplasts. The results confirmed that 4',6-diamidino-2-phenylindole (DAPI), Hoechst 33258 and mithramycin could be used as real vital stains, though their efficiency varied from case to case; among them DAPI showed best effect. The fluorescent vital staining technique offered a useful means fori-dentification and selection of heterokaryons in gametoplast manipulation studies.
