Tea Plant Tissue Culture Techniques And Bacteriostat Selection In Genetic Transformarion

Many problems are still remained in tea tissue culture, such as etiolation, abnormal phenomenon, instability and poor repeatability. In anther hand, difficult regeneration in vitro and low genetic transformation efficiency have been one of the difficulties of tea plant biotechnology. Therefore, some researches in this field were carried and the main conclusion is as following:(1) GA3(5mg/1) used alone in tea culture was not only inhibited tea seedling growth, but also resulted in abnormal phenomenon. Thus, high amount of GA3shouldn’t be added to proliferative medium. Its concentration should be reduced or matched with appropraite auxin if it was requied. High concentration of NAA (≥0.5mg/1) promoted the induction of callus, while inhibited the growth of seedling, so it was better to ruduce the concentration to lower than0.1mg/1in proliferative culture. And0.1mg/1IB A was as well as available.(2) The stem segments were superior to leaves for induction of calli and roots. There was no buds induced from the calli exclude the ones from stems with axillary bud induced sprout in axillary bud primordium. And multiple shoots from stem tips were obtained. Above all, stems with axillary bud or stem tips can be used as transformants.(3) Etiolation and abnormal phenomenon were much serious during subculture of tea. The effect of different concentration of metal ions and hormones on tissue culture seedling was compared. The results showed that deficiency of iron salts, Mg2+and Zn2+was one of the reasons of etiolation. And the abnormal phenomenon could be diminished through alternative culture by MS with2mg/16-BA and0.1mg/1NAA and MS without hormone.(4) The influence of bacteriostat on explants in tea transformation showed that cefotaxime and carbenicillin reduced the rate of survival and proliferation, while lower concentration of timentin (200-300mg/1) had no apparent influence on tea explants. Consideration suppression Agrobacterium, timentin can be used for improving the genetic transformation efficiency of tea plants.