To demonstrate the expression profiling of Xanthomonas oryzae pv.oryzae(Xoo) in vitro and in planta,DNA microarrays of 371 genes potentially associated with pathogenicity and virulence were used to compare the transcr...To demonstrate the expression profiling of Xanthomonas oryzae pv.oryzae(Xoo) in vitro and in planta,DNA microarrays of 371 genes potentially associated with pathogenicity and virulence were used to compare the transcriptional level alteration of the wild-type strain PXO99A and gene deletion mutants ΔgacAxoo and ΔfleQxoo of Xoo grown in the rich medium NBY vs.hrp-inducing minimal medium XOM2 or leaf tissues of rice.Results indicated that 17 and 38 genes of PXO99A were differentially expressed in XOM2 and the leaf tissues of rice relative to NBY,respectively.Twenty-eight genes of ΔgacAxoo grown in XOM2 and 12 genes of ΔfleQxoo in NBY were differentially expressed relative to PXO99A.The identification of differentially-expressed genes,GacAxoo-and FleQxoo-regulons and novel candidate genes of Xoo strains would provide us the target genes for further functional analysis in pathogenesis of Xoo.展开更多
为了深入揭示高温热害对水稻生产的影响,该研究采用南京和昆山水稻田间试验数据,驱动ORYZA V3作物模型模拟孕穗期、开花期、灌浆期单一及多阶段耦合热害情景,解析生育期动态、产量构成与水分利用效率(water use efficiency,WUE)响应规...为了深入揭示高温热害对水稻生产的影响,该研究采用南京和昆山水稻田间试验数据,驱动ORYZA V3作物模型模拟孕穗期、开花期、灌浆期单一及多阶段耦合热害情景,解析生育期动态、产量构成与水分利用效率(water use efficiency,WUE)响应规律。结果表明:1)发育速率转折阈值:高温积温(heat degree-days)HDD≤11.1℃·d(南京)和20.7℃·d(昆山)时,水稻生育期缩短,而超阈值后水稻发育速率显著降低,昆山极端热害下生育期延长28 d;2)WUE关键阈值:水稻在高温热害下WUE持续下降,遭遇开花-灌浆期耦合热害且HDD≥40℃·d时非线性衰退提速,极端热害下降至16.99%(南京)和16.80%(昆山);3)多阶段耦合热害效应显著:多阶段耦合热害触发产量非线性崩塌,最高减产达79%(南京)和77%(昆山),单阶段热害减产仅在15%以内;4)高温热害通过改变水稻生殖生长期的碳-水耦合平衡,引发水分利用效率断崖式下降,建议采用灌溉制度优化和种植时段调整构建适应性调控技术体系。该成果可为应对气候变化下双重气候风险(干旱与热浪复合)的水稻适应性管理提供科学依据。展开更多
文摘To demonstrate the expression profiling of Xanthomonas oryzae pv.oryzae(Xoo) in vitro and in planta,DNA microarrays of 371 genes potentially associated with pathogenicity and virulence were used to compare the transcriptional level alteration of the wild-type strain PXO99A and gene deletion mutants ΔgacAxoo and ΔfleQxoo of Xoo grown in the rich medium NBY vs.hrp-inducing minimal medium XOM2 or leaf tissues of rice.Results indicated that 17 and 38 genes of PXO99A were differentially expressed in XOM2 and the leaf tissues of rice relative to NBY,respectively.Twenty-eight genes of ΔgacAxoo grown in XOM2 and 12 genes of ΔfleQxoo in NBY were differentially expressed relative to PXO99A.The identification of differentially-expressed genes,GacAxoo-and FleQxoo-regulons and novel candidate genes of Xoo strains would provide us the target genes for further functional analysis in pathogenesis of Xoo.
