In order to identify and verify crucial genes that regulate the stress resistance of poplar， based on the RNA-seq data of poplar（Populus davidiana × P.alba var. Pyramidlis， cv ‘Shanxin’） leaves induced by Trichodermaasperellumon or Alternaria alternata， a key responding gene was cloned and named as PdPapWRKY51. In silico analysis showed that the coded protein of PdpapWRKY51 was a IIc class transcription factor of the WRKY family and a non-transmembrane hydrophilic protein localized in the nucleus. The tissue-specific expression profile of PdPapWRKY51 in poplar seedlings was investigated through real-time quantitative polymerase chain reaction（RT-qPCR）. The results showed that PdPapWRKY51 was broadly expressed in plants and the highest expression was found in roots. The expression of PdPapWRKY51 was investigated after 48 hours of induction by salt， alkali， PEG（Polyethylene glycol）， five soil-borne plant fungal pathogens or phytohormones respectively. The results showed that the PdPapWRKY51 expression level was greatly affected by alkali stress. Fusarium oxysporum， Cytospora chrysosperma or A. alternata induction significantly up-regulated PdPapWRKY51 expression in the apex respectively. F. oxysporum induction significantly up-regulated PdPapWRKY51 in the leaf. C. chrysosperma and A. alternata induced significantly higher PdPapWRKY51 expression in the root. PdPapWRKY51 expression could be broadly induced by SA（salicylic acid） in plants. When induced by JA（jasmonic acid） or ABA （abscisic acid）， the PdPapWRKY51 expression was up-regulated in the apex but down-regulated in the root. The results revealed the tissue-specific expression patterns of PdPapWRKY51 gene in respond to multiple induction， and would provide a basis for further elucidating the function of PdPapWRKY51 and insights into breeding novel stress-resistant poplar cultivars through modifying PdPapWRKY51 expression.
%U https://bbr.nefu.edu.cn/EN/10.7525/j.issn.1673-5102.2021.06.009