Research On Tissue Culture And Regeneration Of Sphagnum

Peat moss is a special kind of moss,belonging to Sphagnaceae,Sphagnales.On the evolution,peat moss belongs to the relatively primitive taxa and has unique structures.The protonema has two different forms,filaments and thallus protonema and the leaf has no rib.There are two different types of cells in the mature leaf of peat moss,the green cells and colorless cells.Peat moss is an excellent material in the study of cell differentiation and plant evolution,because of the original evolution status and unique structures.However,the tissue culture of peat moss limited to cormus,could not be more in-depth research in developmental biology.Existing researchs just focus on the ecological characteristics and the object of study is mainly aimed at the wild state of materials.But the homogeneity and stability of samples couldn't be guaranteed and the result is extensive.Under the condition of artificial culture,to obtain consistent material is the basic way to solve these problems.Peat moss found in mountain humid regions or the swamp,is the main plant populations in alpine wetland and the ecological status is very important.Peat moss has a lot of important applications in many different areas.For example,we can use peat moss for culture matrix,wound dressings,energy sources.Sometimes we can use peat moss to make wallpaper and construction paper.However,the main source of commercial use of peat moss is still relying on wild resources.So it could produce greatly damaged on the natural environment.China is the largest exporter of wild peat moss,urgently need to establish an artificial reproduction technology to meet the needs of application.Therefore,we conducted a series of trying to set up the system of peat moss tissue culture,especially the cultivation of protonemata.And on this basis,we carry out the culture conditions and regeneration research of Sphagnum,so as to create conditions for the further artificial breeding,growth and development research and the establish of genetically modified system.The results show that,the pH in peat moss growth environment is changeful in the natural environment,between 3.5 and 6.But Under laboratory conditions,the pH range of Sphagnum growth is relatively narrow.The optimal pH for cormus is 5-6,and for protonema the optimum pH is 6.High or low pH condition can significantly inhibit the growth of peat moss.Peat moss is also sensitive to the concentration of nitrogen.The protonema is suitable for growing in lower nitrogen environment than cormus.To be specific,cormus grow well when the concentration of nitrogen is between 8 mmol/L and 40 mmol/L.Considering the two factors influence on peat moss growing,we conclude that Sphagnum grow most rapidly when the pH of 6 and the nitrogen concentration of 40 mmol/L after culturing two months.During the process of studying Sphagnum regeneration,we found that the regeneration of peat moss tissue fragments is various.No matter the fragments of stem or little leaf,they can regenerate three different types of tissue structures,including filamentous protonema,thallus protonema and buds.But there are some difference between the three regeneration types in the regeneration rates and time.In general,the first appearing regeneration type is filamentous protonema and its regeneration rate is much higher than other two types.There are no obvious difference in regeneration rates and time between thallus protonema and buds.