Studies On Artificial Culture Conditions Optimization And Influence Factors Of Desert Moss(Syntrichia Canninervis Mitt. )

Desert moss Syntrichia caninervis Mitt., which is widely distributed in semiarid and arid regions, has strong abilities to drought stress, and asexual reproduction. It takes years or even decades to form the moss crust from engraftment development. The present research aims to explore the methods of micropropagation of Syntrichia caninervis, and satisfy the need for mass production of materials in practical, also provide theory basis for rebuilding moss-dominated soil crusts later. In this paper,we took the young shoots of the wild plants as explants and compared the effects of different culture media,hormone,sugar on the gametophytes formation and branch of Syntrichia caninervisby artificial culture indoor, and we also studied the influences of Syntrichia caninervis sampled from two different microhabitats and water conditionson growth,morophological,photochemical efficiency and physiological characteristics of sand-cultiviated Syntrichia caninervis. Wehave obtained axenic gametophytes of Syntrichia caninervis in virto,optimized artificial conditions of Syntrichia caninervisand acquired the optimum water condition for growth of sand-cultiviated shoots of Syntrichia caninervis in the process of transplanting cultured materials from lab to the field. The main results are as follows:1.The microcentrifuge was used to rorate sterylize, three sanitizer include sodium hypochlorite, mercury bichloride, alcohol with different concentrations and different disinfection time were setted to study the effect of gametophyte formation and branch of Syntrichia caninervis.The result showed the 0.5% sodium hypochlorite with 20 s rotate dieinfected time and 1% sodium hypochlorite with 15 s rotate disinfected time are most suitable for the sterlization of Syntrichia caninervis,the survival rate reached 97.33%、98.67%.2. Knop media is most suitable for the cultivation of Syntrichia caninervis, followed by the modified Knop, the survival and non-pollution rate reached 88%�'�90%、80%�'� 85%; The phytohormone has an obvious impact on the branch of gametophytes.The best treatment in terms of gametophytes branch rate was 0.01 g/L IAA and 0.1 g/L 2,4-D; The addition of sugar had a bad effect on the cultivation of Syntrichia caninervis.3. The substrate hadsignificant influence on the growth of Syntrichia caninervis.The plant density and biomass of Syntrichia caninervis on the sand was highest; the height of plant on the perlitewhich was comparised higher thansand and vermiculite(p<0.05), while has not significant difference compared with mixed media(sand: perlite: vermiculite=1:1:1)(p>0.05).4. Compared to the sand-cultural seedlings from understory, the value of shoots coverage, density and biomass of cultivated shoots from intershrub were higher, while the shoot height showed the opposite results; There were significant differences among sand-cultural seedlings from different microhabitat in leaf width from middle and bottom of shoots, as well as the leaf hair point length from top of shoots(p<0.05). However, no obvious morphological differences in leaf length and midrib width were observed(p>0.05).5. The contents of chlorophyll which was medium watered treatment higher than the drought treatmentand fully wateredtreatment. The soluble sugar content, free proline content and the activities of antioxidant enzymes(CAT, POD, SOD) were significant higher in the process of drought treatment and fully wateredtreatment than that in medium watered treatment(p<0.05). MDA was the highest under the drought treatment condition.Thus,medium watered treatment should be taken into consideration for implementing field engraftment of artificial-cultivated biocrust mosses.