【目的】以襄麦冬(Liriope spicata var.prolifera Y. T. Ma)为对象,通过转录组学技术筛选、发掘相关功能基因,以期解析襄麦冬块根中甾体皂苷的生物合成。【方法】选取襄麦冬始见期块根样本和膨大期块根样本,使用转录组测序、序列注释...【目的】以襄麦冬(Liriope spicata var.prolifera Y. T. Ma)为对象,通过转录组学技术筛选、发掘相关功能基因,以期解析襄麦冬块根中甾体皂苷的生物合成。【方法】选取襄麦冬始见期块根样本和膨大期块根样本,使用转录组测序、序列注释分析、RT-qPCR等技术,验证并筛选多个与甾体皂苷合成相关的关键基因。【结果】共获得2个襄麦冬转录组的多条高质量序列(始见期样本59 405 731条;膨大期样本71 478 348条),共88 239条被注册到GO、COG、KOG、KEGG等数据库中。其中,通过GO数据库注释了42 388条拼接序列(分为3大类60个功能亚类),并在2个襄麦冬转录组中发现5563个差异表达基因;通过比对COG/KOG数据库,发现10 077条序列可注释到23个COG类群,8187条序列可注释到25个KOG类群,均与襄麦冬块根的生长及代谢有关。基于KEGG数据库的代谢通路分析表明,26 626条拼接序列可映射到不同的KEGG途径中,1981个差异表达基因被映射到227条KEGG途径;进一步筛选出43个可能参与甾体皂苷生物合成的差异表达基因后,并选取其中8个关键基因进行qRT-PCR验证。8个基因在襄麦冬不同生长时期表现出不同的表达量,与甾体皂苷合成有关的基因表达上调,且表达差异与转录组分析结果一致。该结果进一步验证了甾体皂苷在襄麦冬块茎中的生物合成途径,同时说明甾体皂苷的合成代谢与襄麦冬生长阶段性之间的相关性。【结论】初步揭示与襄麦冬甾体皂苷生物合成有潜在关联的基因和代谢通路,为今后进一步研究襄麦冬甾体皂苷的主要关联基因及代谢通路的功能以阐明其合成机理奠定了基础。展开更多
To estimate the impact of crop rotation on the pathotype and genetic structure of Phythophthora sojae in fields, 372 isolates of P. sojae were obtained from long-term localisation experimental fields in Heilongjiang P...To estimate the impact of crop rotation on the pathotype and genetic structure of Phythophthora sojae in fields, 372 isolates of P. sojae were obtained from long-term localisation experimental fields in Heilongjiang Province of China. The hypocotyl inoculation method was used to characterize the virulence of P. sojae on 13 differential cultivars, and the amplified fragment length polymorphism（AFLP） technique was used to analyze difference in the genetic structure of P. sojae. The results indicated that an abundant diversity of genetic structures and pathotypes of P. sojae, a more uniform distribution of pathotypes and less dominance of pathotypes occurred in corn-soybean and wheat-soybean rotation fields than in a continuous soybean mono-cropping field. These findings suggested that P. sojae did not easily become the dominant race in rotation fields, which maintain disease resistance in soybean varieties. Therefore, the results of this study suggested that Phytophthora stem and root rot of soybeans could be effectively controlled by rotating soybeans with non-host crops of corn and wheat.展开更多
基金Supported by the Special Fund for Agro-scientific Research in the Public Interest(201303018)the National Natural Science Foundation of China(31370449)
文摘To estimate the impact of crop rotation on the pathotype and genetic structure of Phythophthora sojae in fields, 372 isolates of P. sojae were obtained from long-term localisation experimental fields in Heilongjiang Province of China. The hypocotyl inoculation method was used to characterize the virulence of P. sojae on 13 differential cultivars, and the amplified fragment length polymorphism（AFLP） technique was used to analyze difference in the genetic structure of P. sojae. The results indicated that an abundant diversity of genetic structures and pathotypes of P. sojae, a more uniform distribution of pathotypes and less dominance of pathotypes occurred in corn-soybean and wheat-soybean rotation fields than in a continuous soybean mono-cropping field. These findings suggested that P. sojae did not easily become the dominant race in rotation fields, which maintain disease resistance in soybean varieties. Therefore, the results of this study suggested that Phytophthora stem and root rot of soybeans could be effectively controlled by rotating soybeans with non-host crops of corn and wheat.
