大豆疫霉菌侵染对大豆木质素含量及合成关键基因表达的影响

为探究大豆木质素含量及合成关键基因在与大豆疫霉菌互作过程中的变化趋势及相关性,利用大豆疫霉菌株P6497接种大豆品种Williams,分别于6,8,10和15 d分析了根部组织木质素含量及合成相关基因的表达。结果表明:根组织中木质素含量在疫霉菌侵染过程中积累速度显著增加;对木质素合成过程中9个合成关键基因表达模式分析表明,PAL、C4H和F5H表达水平在所选4个时间点均显著高于未接种对照;CCo AOMT在接种后第8,10和15天3个时间点的表达水平显著高于对照;4CL的表达在接种后第10和15天时比对照上调超过100倍;CAD和CCR表达水平分别在接种后8和10 d与对照存在显著差异;C3H和COMT的表达量在处理组和对照组中差异不显著。在接种样品中,C4H、4CL和CCR基因表达与木质素含量变化模式呈显著正相关。以上结果表明:大豆根部木质素积累受疫霉侵染诱导,暗示木质素参与大豆与疫霉互作过程,同时根据试验结果推测C4H、4CL和CCR是诱导木质素含量提高的关键基因。

Lignin Content and Expression of Key Biosynthetic Genes in Soybean upon Infection by P.sojae

To explore the variation tendency of soybean lignin content and key biosynthetic genes expression in the progress of soybean and Phythophthora sojae interaction and the relationship between them.The lignin contents and key biosynthetic genes expression of Williams roots were analyzed at 6,8,10 and 15 days post inoculation(dpi) with P.sojae P6497 isolate.The resuits showed that the lignin content in infected tissues showed a higher accumulations rate when compared with uninfected control.The expression analysis of the 9 key biosynthenic genes exhibit that PAL,C4H and FSH were significantly up-regulated in infected samples than that in control at all selected time points,CCoAOMT was significantly higher at 8,10,15 dpi,4CL showed more than 100 folds higher than control at 10 and 15 dpi,CAD and CCR were significantly higher at 8 and 10 dpi respectively,the remain two genes(C3H and COMT) showed no significantly difference between inoculated and control samples.The further analysis found that the expression of C4H,4CL and CCR variation tendency in inoculated samples were significantly positive correlated with lignin content.The above results demonstrated that the content of soybean lignin was induced by P.sojae infection,implying that lignin may participate in the interaction between soybean and P.sojae,and C4H,4CL and CCR gens plays a crucial role in lignin synthesis induced by P.sojae in soybean.