关键词: 棉花, 转录因子, GhWRKY25, 抗逆, 植物激素

Abstract: Cotton (Gossypium hirsutum L.) is an important economic crop, which plays pivotal roles in industry and social life. However, many uncontrolled environmental factor, such as drought and saline,  affect plant area,  yield and quality of cotton. Currently,  molecular breeding for improving the tolerance of cotton cultivars against various stresses has become the focus of research. In this study,  a novel WRKY gene was cloned from cotton,  designated as GhWRKY25. The GhWRKY25 protein contains two typical WRKY domain,  in which a zinc finger motif is located in the C\|terminal. Phytogenic analysis showed that GhWRKY25 belongs to the class Ⅰ WRKY protein,  and has highest homology with TcWRKY3 in Theobroma cacao. The results of qPCR analysis showed that GhWRKY25 is constitutively expressed in various cotton organs with high mRNA level in flowers. The expression of GhWRKY25 was up\|regulated in cotton plants under the external\|applying SA, JA,  ABA and GA3. When cotton plants were treated with drought and NaCl,  the expression level of GhWRKY25 significantly increased compared with the control. The above results showed that GhWRKY25 is able to response to various hormones,  drought and salt stresses,  indicating that it could play important roles in cotton tolerance to different stress, and provide a basis for futher reaearch on GhWRKY25 function.

Key words: upland cotton, transcription factor, GhWRKY25, stress tolerance, phytohormone