米象触角感器的扫描电镜观察

应用扫描电镜分别观察了米象Sitophilus oryzae(Linnaeus)(鞘翅目:象甲科)雌、雄成虫的触角及感器,比较研究了雌、雄成虫触角形态、感器类型、数量和分布上的差异。结果表明,米象成虫的触角为膝状,由柄节、梗节和鞭节(6个亚鞭节)组成。成虫触角上共有9种类型的感器:毛形感器、刺形感器、锥形感器、叉形感器、锯齿形感器、槽纹形感器、B?hm氏鬃毛、指形感器以及腔形感器。其中,毛形感器的数量最多,锯齿形感器和槽纹形感器在已有的象甲科昆虫资料中尚未见报道。根据这些感器的分布、形态特征,结合已有的文献描述,分析了各感器可能具有的功能。     

Genetic Analysis of Rice Mutants Identifies a New Locus at the Pi-ta Region Controlling Pathogen Recognition

Understanding the molecular mechanisms of host and parasite interactions should facilitate the development of novel strategies to control plant diseases. Host interactions with biotrophic and hemi-biotrophic pathogens are known to follow a gene-for-gene specificity. The plant expresses a resistance （R） gene that is effective in preventing disease in response to pathogen races expressing the corresponding avirulence gene. We are studying the interaction mechanisms of the R gene, Pi-ta, in rice with the corresponding avirulence gene, A VR-Pita, found in the hemi-biotrophic pathogen, Magnaporthe oryzae （formerly Magnaporthe grisea）. Pi-ta is a putative cytoplasmic receptor with a centrally localized nucleotide-binding site and leucine rich domain at the carboxyl terminus （Bryan et al., 2000; Jia et al., 2000）. AVR-Pita is predicted to be a metalloprotease （Jia et al., 2006b）. The putative processed protein, AVR-Pita176, has been shown to interact with the Pi-ta protein （Bryan et al., 2000; Jia et al., 2000）.     

我国水稻白叶枯病和条斑病发生与防控研究进展

培育和种植抗病品种和研发新型绿色杀菌剂是防治水稻白叶枯病和条斑病的有效措施。最近几年有关稻黄单胞菌Xanthomonas oryzae致病效应蛋白调控水稻抗(感)病性研究取得了突破性进展, 为水稻抗性品种培育提供了新思路、新策略。本文对稻黄单胞菌-水稻互作系统中已知的TALE效应蛋白与水稻抗(感)病基因(R 或 S)的对应关系进行了归纳, 就tal基因与水稻R或S基因的协同进化进行了分析, 结合生物农药和高效低毒杀菌剂的应用现状, 提出了我国水稻白叶枯病和水稻条斑病绿色防控关键策略。     

Integrated pest management programme for cereal blast fungus Magnaporthe oryzae

Magnaporthe oryzae, the causal agent of blast diseases, is a destructive filamentous fungus that infects many plants including most economically important food crops, rice, wheat, pearl millet and finger millet. Magnaporthe oryzae has numerous pathotypes because of its high host-specificity in the field. The Oryza pathotype (MoO) of M. oryzae is the most devastating pathogen of rice, causing 10–30% yield loss in the world. On the other hand, the Triticum pathotype (MoT) causes blast disease in wheat, which is now a serious threat to wheat production in some South American countries, Bangladesh and Zambia. Because of low fungicide efficacy against the blast diseases and lack of availability of resistant varieties, control of rice and wheat blast diseases is difficult. Therefore, an integrated management programme should be adopted to control these two diseases in the field. Here, we introduced and summarized the classification, geographical distribution, host range, disease symptoms, biology and ecology, economic impact, and integrated pest management (IPM) programme of both rice and wheat blast diseases.     

黑龙江省和海南省PWL基因家族在稻瘟病菌中的分布及变异

【目的】了解不同稻瘟病菌（Magnaporthe oryzae）菌株群体中PWL基因家族的分布和变异特征，为研究不同稻瘟病菌群体的遗传多样性及特异性提供依据。【方法】通过参考NCBI中公布的无毒基因序列分别对PWL基因家族的启动子区和CDS区设计特异性引物共8对，对2020年采自黑龙江省和海南省不同地区的397个稻瘟病菌单孢分离菌株提取DNA，进行无毒基因的PCR扩增并通过琼脂糖凝胶电泳检测，从检测结果中分别选取囊括不同地区的代表菌株对扩增片段进行测序分析。测序结果与NCBI中相应无毒基因启动子区和CDS区的碱基与氨基酸序列进行比较分析。【结果】在PCR电泳检测结果中，PWL1在所有菌株中均未检测出；PWL2、PWL3和PWL4在黑龙江省和海南省中均扩增出特异性片段，说明这3种基因在两省中均有分布并分别存在不同的分布频率与变异类型。其中PWL2在黑龙江省和海南省中分布频率最高，分别为98.14%和100%;PWL3和PWL4在两省中的分布频率具有显著差异，这2种基因在黑龙江菌株中频率分别为89.30%和82.79%，而在海南菌株中均为5.49%。通过对无毒基因组合进行分析，结果显示，组...     

菠萝泛菌与水稻白叶枯病菌双重PCR检测方法的建立与应用

近年来水稻发生了一种由菠萝泛菌Pantoea ananatis引起的新型细菌病害，其发生时期与白叶枯病相近，病症与白叶枯病类似。为了实现该病害与白叶枯病的快速检测，本研究基于泛菌属看家基因acnA,通过序列比对，设计了22对特异性引物，分别与已知的白叶枯病菌检测引物XOO80进行配对并筛选，建立了一种双重PCR检测方法，可从菠萝泛菌和白叶枯病菌中分别扩增出910 bp和162 bp的特异性条带，而其他10种非目标细菌均未有扩增条带，25μL体系中可稳定地从至少1 pg/μL的基因组DNA模板中扩增出特异性条带。本研究建立的菠萝泛菌与水稻白叶枯病菌双重PCR检测方法具有良好的特异性和灵敏度，为水稻细菌病害病原鉴定及防治提供了技术支撑。