Abstract:Two T₅ transgenic wheat lines G19-X59 and G19-X61 with W23 gene were used as materials, 15% PEG-6000 was used to simulate the drought stress in hydroponic culture, the root development characteristics of transgenic wheat lines and photosynthetic physiology indexes related to drought resistance were investigated. The results indicated that photosynthetic rate (Pn) and transpiration rate (Tr) of all the wheat materials decreased under drought stress, whereas those of the transgenic wheat lines were not significantly changed. The Pn and Tr values of transgenic wheat lines were extremely significantly higher than that of the control Jimai 19. The transgenic lines were also found to have more developed root system than the control under both normal water supply and drought stress treatments. There were also extremely significant difference in total root length, root surface area and root volume between transgenic lines and the control. The results showed that the transgenic lines G19-X59 and G19-X61 could maintain high level of photosynthesis and thereby have strong resistance to drought stress.