Overexpression of TaWRKY14 transcription factor enhances accumulation of chlorogenic acid in Taraxacum antungense Kitag and increases its resistance to powdery mildew

WRKY transcription factors play a critical role in metabolism and stress responses in plants, but few WRKYs have been reported in Taraxacum antungense . Here, a multiple stress-inducible gene, TaWRKY14 , was isolated from T. antungense . TaWRKY14 was localized to the nuclei, and phylogenetic analysis indicated that TaWRKY14 shared the highest identity to WRKY40 in Salvia miltiorrhiza . TaWRKY14 was highly expressed in roots, and up-regulated by salt and drought stress, salicylic acid treatment and powdery mildew. TaWRKY14 -overexpressing transgenic lines had higher chlorogenic acid concentration and high expression of TaPAL1 . The yeast one-hybrid assay proved that TaWRKY14 bond to the W-box of proTaPAL1 . Additionally, field experiments showed that TaWRKY14 -overexpressing T. antungense lines have higher powdery mildew resistance than the wild-type. Our results demonstrated that TaWRKY14 can regulate CGA biosynthesis and play an important role in resistance to powdery mildew in T. antungense . TaWRKY14 transgenic T. antungense can be used for further evaluation as a new germplasm resource.