Chinese Bulletin of Botany ›› 2018, Vol. 53 ›› Issue (1): 59-71.DOI: 10.11983/CBB16257

• EXPERIMENTAL COMMUNICATIONS • Previous Articles     Next Articles

Breeding of MtDREB2A Transgenic Soybean by an Optimized Cotyledonary-Node Method

Guodong Wu, Yu Xiu, Huafang Wang*()   

  1. Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education, National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China
  • Received:2016-12-23 Accepted:2017-05-04 Online:2018-01-01 Published:2018-08-10
  • Contact: Huafang Wang


Orthogonal factorial experiments and histochemical GUS staining were combined to optimize the genetic transformation system of Glycine max cv. ‘Dongnong 50’ and transfer the key gene MtDREB2A for drought resistance into the soybean. Sterile of soybean seeds used as explants with NaClO solution and Cl2 gas fumigation methods reached 98.67% and 93.33% germination, respectively. Histochemical staining rate of the tissues transformed with GUS by the cotyledon node method was 68.33%, significantly higher than that by the hypocotyl (14.00%) and embryo tip (0.67%) methods (P<0.05). The cotyledon node-transformed GUS gene was up to 72.00% in germinated sterile seeds for 5 days, mediated by Agrobacterium tumefaciens cultured at 25°C, OD600 0.9, and co-cultured for 5 days. The shoots were induced and differentiated with cotyledon node-transformed GUS up to 3.33% by optimal recovery culture for 5 days and were screened on culture medium containing phosphinothricin (3 mg·L-1), cefotaxime sodium (200 mg·L-1) and carbenicillin (300 mg·L-1). The transgenic efficiency was 1.11% with the optimized soybean genetic transformation system. The MtDREB2A transgenic plant roots of soybean ‘Dongnong 50’ were more dense and both taproot length and lateral root number were significantly longer and greater than those of the control (P<0.05). The study verified that the MtDREB2A gene plays a role in promoting soybean root growth, which lays a solid foundation and provides a theoretical basis for the gene using in drought resistance breeding of soybean.

Key words: soybean, optimization of gene transformation system, GUS, MtDREB2A, root enhancement