Abstract
WRKY type transcription factors (TFs) play crucial roles in the growth and development of plants. However, a comprehensive analysis of the WRKY family members in a valuable Chinese herbal orchid, Bletilla striata, or in other orchids, is limited. In this study, WRKY gene family was screened out from the transcriptome data of Bletilla striata by bioinformatics method. The 29 WRKY TFs that were identified from the B. striata genome and named BsWRKY1 to BsWRKY29 were divided into three clades: group Ⅰ (involving 8 WRKY sequences), group Ⅱ (18) and group Ⅲ (3), in which group Ⅱ was further divided into 5 subgroups: Ⅱ-a (involving 1 WRKY sequences), Ⅱ-b (5), and Ⅱ-c (3), Ⅱ-d (7), Ⅱ-e (3). EST-SSR marker mining test showed that 10 markers could be stably amplified with obvious polymorphisms among 4 landraces. Our data suggest that BsWRKY genes may work together to regulate plant growth and development. In different subcellular locations, BsWRKY genes not only played its own functions, but also coordinated the regulation of the whole life activities. Taken together, these results provided a theoretical basis for further studies on the gene functions and regulatory mechanisms of what in B. striata.