Abstract: [Objective] To study the biological function of jujube WRKY transcription factor (TF) and interaction mechanisms between jujube and ‘Candidatus Phytoplasma ziziphi’, we analyzed the response of jujube WRKY to ‘Candidatus Phytoplasma ziziphi’ and salicylic acid or methyl jasmonate treatments.[Method] The putative jujube WRKY TFs were explored and identified from NCBI and transcriptomics database by homologous alignment, and their structure and bioinformation were analyzed using SMART software. Six differentially expressed jujube WRKY were screened from the transcriptomics analyses, and the expression changes of them were verified by real time PCR during the development of jujube witches' broom (JWB) of Ziziphus jujuba ‘Huizao’. The embryo cultured seedling of jujube (Z. jujuba ‘Fengmiguan’) were sprayed with 0.1 mmol·L^-1 salicylic acid (SA) and methyl jasmonate (MeJA), and relative expression levels of the selected six WRKY genes were analyzed by qPCR.[Result] 69 putative jujube WRKY TFs were confirmed and named ZjWRKY1-69, which could be divided into three groups:GroupⅠ, GroupⅡ, GroupⅢ. GroupⅠ contained 17 members, whereas groupⅡ can be further divided into GroupⅡa, b, c, d, e subgroups, contained 3, 11, 15, 3, and 9 members, respectively. GroupⅢ included 11 members. 43 of 69 putative jujube WRKY genes were mapped to the 11 jujube chromosome, and were unevenly located on different chromosomes such as no WRKY on chromosome 7. Most of the jujube WRKY proteins contained conserved WRKYGQK sequences, while two WRKY proteins (ZjWRKY23 and ZjWRKY46, GroupⅡc) varied to WRKYGKK. The WRKY TFs in GroupⅠ contained 10 conserved motifs, the number of motifs in GroupⅠ was the largest among the three groups. The conserved motif type and number of WRKY protein are similar in the same group. The expression pattern of 28 jujube WRKY genes were detected to be different during the JWB developing in jujube leaves, and differentially expressed ZjWRKY genes were mainly detected from 39 to 52 weeks after infection. The expression levels of ZjWRKY8, ZjWRKY52, ZjWRKY61, and ZjWRKY69 were significantly up-regulated during JWB developing. After SA treatment, the expression levels of ZjWRKY42 and ZjWRKY52 were significantly increased. The expression levels of ZjWRKY42 and ZjWRKY61 were significantly up-regulated in response to MeJA treatment.[Conclusion] 69 jujube WRKY TFs were preliminarily confirmed, which can be divided into three groups. 43 WRKY genes were mapped to 11 chromosomes,no WRKY genes on Chr 7. After the infection of ‘Candidatus Phytoplasma ziziphi’, the expression of ZjWRKY5, ZjWRKY8, ZjWRKY42, ZjWRKY52, and ZjWRKY61 were induced. The expression of ZjWRKY42 and ZjWRKY52, ZjWRKY42 and ZjWRKY61 were significantly up-regulated by SA and JA treatments, respectively.

Key words: Ziziphus jujuba, WRKY, ‘Candidatus Phytoplasma ziziphi’, salicylic acid, methyl jasmonate