Optimization of conditions for tetraspore release and assessment of photosynthetic activities for different generation branches of Gracilaria lemaneiformis Bory  

作　　者：王志远 王广策 牛建峰 汪文俊 彭光 

机构地区：[1]College of Marine Science and Engineering,Tianjin University of Science and Technology [2]Key Laboratory of Experimental Marine Biology,Institute of Oceanology,Chinese Academy of Sciences

出　　处：《Chinese Journal of Oceanology and Limnology》2010年第4期738-748,共11页中国海洋湖沼学报（英文版）

基　　金：Supported by the National Natural Science Foundation of China(No.30830015);the National Key Technology Research and Development Program of the 11th Five-Year Plan(No.2006BAD09A04);the National High Technology Research and Development Program of China(863Program,Nos.2006AA10A402,2007AA09Z406,2006AA05Z112,2006AA10A413)

摘　　要：Gracilaria lemaneiformis Bory is an economically important alga that is primarily used for agar production.Although tetraspores are ideal seeds for the cultivation of G.lemaneiformis,the most popular culture method is currently based on vegetative fragments,which is labor-intensive and time-consuming.In this study,we optimized the conditions for tetraspore release and evaluated the photosynthetic activities of different colonies formed from the branches of G.lemaneiformis using a PAM(pulse-amplitude-modulated) measuring system.The results showed that variations in temperature and salinityhad significant effects on tetraspore yield.However,variations in the photon flux density(from 15 μmol m-2 s-1 to 480 μmol m-2 s-1) had no apparent effect on tetraspore yield.Moreover,the PAM-parameters Y(I),Y(Ⅱ),ETR(I),ETR(Ⅱ) and Fv/Fm of colonies formed from different branches showed the same trend:parameter values of first generation branches>second generation branches>third generation branches.These results suggest that the photosynthetic activities of different colonies of branches changed with the same trend.Furthermore,photosynthesis in G.lemaneiformis was found to be involved in vegetative reproduction and tetraspore formation.Finally,the first generation branches grew slowly,but accumulated organic compounds to form large numbers of tetraspores.Taken together,these results showed that the first generation branches are ideal materials for the release of tetraspores.Gracilaria lemaneiformis Bory is an economically important alga that is primarily used for agar production.Although tetraspores are ideal seeds for the cultivation of G.lemaneiformis,the most popular culture method is currently based on vegetative fragments,which is labor-intensive and time-consuming.In this study,we optimized the conditions for tetraspore release and evaluated the photosynthetic activities of different colonies formed from the branches of G.lemaneiformis using a PAM（pulse-amplitude-modulated） measuring system.The results showed that variations in temperature and salinityhad significant effects on tetraspore yield.However,variations in the photon flux density（from 15 μmol m^-2 s^-1 to 480 μmol m^-2 s^-1） had no apparent effect on tetraspore yield.Moreover,the PAM-parameters Y（I）,Y（Ⅱ）,ETR（I）,ETR（Ⅱ） and Fv/Fm of colonies formed from different branches showed the same trend：parameter values of first generation branches〉second generation branches〉third generation branches.These results suggest that the photosynthetic activities of different colonies of branches changed with the same trend.Furthermore,photosynthesis in G.lemaneiformis was found to be involved in vegetative reproduction and tetraspore formation.Finally,the first generation branches grew slowly,but accumulated organic compounds to form large numbers of tetraspores.Taken together,these results showed that the first generation branches are ideal materials for the release of tetraspores.

关 键 词：Gracilaria lemaneiformis Bory TETRASPORE pulse-amplitude-modulated PHOTOSYNTHESIS 

分 类 号：Q948.8[生物学—植物学]