渗透胁迫下内生真菌感染对黑麦草幼苗生长的影响  

Growth characteristics of endophyte-infected and endophyte-free Lolium perenne L. seedlings under osmotic stress conditions

作　　者：任安芝[1] 高玉葆[1] 

机构地区：[1]南开大学生命科学学院,天津300071

出　　处：《生态学报》2003年第11期2307-2317,共11页Acta Ecologica Sinica

基　　金：国家重点基础研究发展规划资助项目 ( G2 0 0 0 0 1 860 1 );国家自然科学基金资助项目 ( 3 0 2 40 0 83 );教育部科学技术研究重点资助项目 ( 0 3 0 46)~~

摘　　要：以含有内生真菌的黑麦草 ( Lolium perenne L.)种子为材料 ,采用 4℃冰箱内和 2 0℃光照培养箱内保存 1 8个月的方式分别构建内生真菌感染 ( EI)和内生真菌非感染 ( EF)的黑麦草种群 ,通过比较 EI和 EF种群在正常条件下 (对照 )和渗透胁迫条件下种子发芽、幼苗生长等方面的差异 ,探讨内生真菌对其宿主植物的直接和间接影响。结果表明 :在对照和胁迫条件下 ,EI种子的发芽势均明显高于 EF种子 ,而只在重度渗透胁迫下 ,EI种子的发芽率才显著高于 EF种子。对于黑麦草幼苗而言 ,渗透胁迫下内生真菌对宿主植物的地上部分和地下部分均有增益作用 ,最终表现为 EI种群的总生物量显著高于 EF种群 ,其中对地上部分的促进作用表现为内生真菌的存在不仅提高了宿主叶片的延伸速率、使 EI叶片比 EF叶片更长、叶面积更大 ,而且在重度胁迫下 ,EI种群的分蘖数也显著高于 EF种群 ;对地下部分的促进作用表现为 EI种群的根系总长度和根干重均高于In their evolution, grasses have developed symbiotic associations with fungi including mycorrhizal fungi that grow in or on the roots, and endophytes that live their entire life cycle within the aerial portion of the host grass, forming nonpathogenic, systemic and usually intercellular associations. Currently, seven genera have been identified, namely, Atkinsonella, Balansia, Balansiopsis, Echinodothis, Epichlo e ¨, Myriogenospora and Parepichlo e ¨, among which the anamorphic (imperfect) stage of Epichlo e ¨ spp. is most closely related to cultivated grasses. In 1982 Morgan Jones & Gams erected the section Albo lanosa to accommodate anamorphic stage of Epichlo e ¨ spp. in the genus Acremonium . In 1996 Glenn et al . reclassified the genus Acremonium section Albo lanosa in a new genus Neotyphodium to separate clavicipitaceous Acremonium from Acremonium with other affinities (usually saprotrophs). The most widely known Neotyphodium endophytes are N. lolii (Latch, Christensen and Samuels) Glenn, Bacon and Hanlin, and N. coenophialum (Morgan Jones & Gams) Glenn, Bacon and Hanlin, which colonize perennial ryegrass (Lolium perenne L.) and tall fescue ( Festuca arundinaceae Schreb.), respectively. Endophytes and their host grasses are mutually symbiotic. On one hand, the grasses provide photosynthates for the fungi; on the other hand, the endophytes may enhance the host's growth and protect the host from biotic stresses (such as mammalian, insect, and nematode herbivores) and abiotic stresses (such as drought and high temperature). Since Read & Camp first reported the close relationship of endophyte infection to drought resistance of tall fescue in 1986, a lot of research work has been done on the effect of endophyte infection on drought resistance of tall fescue, while rather less work has been done on the effect of endophyte infection on drought resistance of perennial ryegrass. Thus in this paper Lolium perenne cv SR4000 infected by Ne

关 键 词：内生真菌 黑麦草 种子萌发 幼苗生长 渗透胁迫 

分 类 号：Q948[生物学—植物学]