生物结皮中优势蓝藻胞外多糖对几种荒漠草本植物种子萌发的影响  

Influence of Exopolysaccharides from Dominant Cyanobacteria in Microbiotic Crusts on Seed Germination of Several Desert Herbaceous Plants

作　　者：龚健[1,2] 张丙昌[2] 索菲娅[1] 

机构地区：[1]新疆大学生命科学与技术学院,新疆乌鲁木齐830046 [2]中国科学院新疆生态与地理研究所中国科学院干旱区生物地理与生物资源重点实验室,新疆乌鲁木齐830011

出　　处：《中国沙漠》2015年第3期639-644,共6页Journal of Desert Research

基　　金：国家自然科学基金项目(41071041;U1203301);中国科学院"西部之光"人才培养项目(RCPY201101)

摘　　要：蓝藻是荒漠生物结皮的重要组成。选取生物结皮中的优势蓝藻(具鞘微鞘藻(Microcoleus vaginatus)、眼点伪枝藻(Scytonema ocellatum)、地木耳(Nostoc commune)),通过提取其胞外多糖,研究了不同蓝藻胞外多糖对荒漠植物种子萌发的影响。结果表明:具鞘微鞘藻、眼点伪枝藻的胞外多糖对粗枝猪毛菜(Salsola subcrassa)的种子萌发表现为低浓度抑制、高浓度促进作用,地木耳的胞外多糖仅在高浓度时对粗枝猪毛菜的种子萌发具有促进作用(p<0.05);具鞘微鞘藻胞外多糖对小花荆芥(Nepeta micrantha)种子萌发无明显的影响作用,但眼点伪枝藻和地木耳对小花荆芥种子萌发具有抑制作用。具鞘微鞘藻、眼点伪枝藻和地木耳胞外多糖对琉苞菊(Hyalea pulchella)种子萌发具有明显的抑制作用。藻种胞外多糖组分的差异和不同种子的生物学特性差异可能是造成不同藻种胞外多糖对种子萌发产生不同影响的主要原因。Desert cyanobacteria are important component in microbiotic crusts.Several dominant cyanobacteria species,including Microcoleus vaginatus,Scytonema ocellatum,and Nostoc commune were selected to extract ex-polysaccharides(EPS)and their effects on seed germination of desert plants were investigated.The results indicated that low concentration EPS of M.vaginatus,and S.ocellatuminhabited seed germination of Salsolasubcrassa,whereas high concentration EPS promoted seed germination of S.subcrassa.EPS of N.commune showed significant effects on seed germination of S.subcrassa with high concentration(p<0.05).EPS of M.vaginatus showed no obvious effects on seed germination of Nepeta micrantha,however,EPS of S.ocellatum,and N.commune had negative effects on seed germination of N.micrantha.EPS of M.vaginatus,S.ocellatum,and N.communeinhabited seed germination of Hyalea pulchella.EPS of the different cyanobacteria had different effect on seed germination,which could be explained by the differences of composition content of EPS and biological character of different seed.

关 键 词：藻类 胞外多糖 粗枝猪毛菜(Salsola subcrassa) 小花荆芥(Nepeta micrantha) 琉苞菊(Hyalea pulch-ella) 

分 类 号：Q945.3[生物学—植物学]