Yield potential, pharmaceutical compounds production and stress tolerance capacity are 3 classes of traits that determine the quality of medicinal plants. The autotetraploid Isatis indigotica has greater yield, higher bioactive lignan accumulation and enhanced stress tolerance compared with its diploid progenitor. Here we show that the transcription factor IiWRKY34, with higher expression levels in tetraploid than in diploid I. indigotica, has large pleiotropic effects on an array of traits, including biomass growth rates, lignan biosynthesis, as well as salt and drought stress tolerance. Integrated analysis of transcriptome and metabolome profiling demonstrated that IiWRKY34 expression had far-reaching consequences on both primary and secondary metabolism, reprograming carbon flux towards phenylpropanoids, such as lignans and flavonoids. Transcript–metabolite correlation analysis was applied to construct the regulatory network of IiWRKY34 for lignan biosynthesis. One candidate target Ii4CL3, a key rate-limiting enzyme of lignan biosynthesis as indicated in our previous study, has been demonstrated to indeed be activated by IiWRKY34. Collectively, the results indicate that the differentially expressed IiWRKY34 has contributed significantly to the polyploidy vigor of I. indigotica, and manipulation of this gene will facilitate comprehensive improvements of I. indigotica herb.

产量潜力，药物化合物的产生和胁迫耐受能力是决定药用植物质量的3类性状。与二倍体祖细胞相比，同四倍体板蓝根具有更高的产量，更高的生物活性木脂素积累和更高的抗逆性。在这里我们表明转录因子Ii WRKY34在四倍体中的表达水平高于在二倍体I. indigotica中的表达水平，对多种性状具有较大的多效性，这些性状包括生物量生长速率，木脂素生物合成以及盐和干旱胁迫耐受性。转录组和代谢组分析的综合分析表明，IiWRKY34表达对初级和次级代谢都具有深远的影响，将碳通量重新编程为苯丙烷，例如木脂素和类黄酮。转录物-代谢物相关性分析用于构建Ii WRKY34木质素合成的调控网络。如我们先前的研究所示，一种候选靶标Ii 4CL3是木脂素生物合成的关键速率限制酶，已被Ii WRKY34确实激活。总体而言，结果表明差异表达的Ii WRKY34大大促进了靛蓝I.的多倍体活力，对该基因的操作将有助于对I. WRKY34的全面改良。I.靛蓝药草。