禾草-内生真菌共生体在草地农业系统中的作用  

Roles of the grass-Neotyphodium association in pastoral agriculture systems

作　　者：南志标[1] 李春杰[1] 

机构地区：[1]兰州大学草地农业科技学院,甘肃草原生态研究所,兰州730020

出　　处：《生态学报》2004年第3期605-616,共12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 86 0 2 ) ;国家高技术研究发展计划 86 3计划资助项目 ( 2 0 0 1 AA2 4 40 81 );国家自然科学基金资助项目 ( 30 0 70 546;39570 51 7)~~

摘　　要：综述了国内外近年对禾草 -内生真菌 (N eotyphodium)的研究进展。全世界现已报道 14种禾草内生真菌 ,与 2 3个属的禾草形成共生体 ,我国已在 13属 2 5种天然草地禾草中发现内生真菌 ,其中发草属 (Descampsia)、大麦属 (H ord eum)和赖草属(L eymus)以往在国际文献中未曾报道。内生真菌在禾草体内产生的生物碱 ,致使采食带菌禾草的马、牛、羊、鹿等家畜产生中毒症状 ,每年给美国、新西兰等国造成的经济损失达 6.4亿美元之多 ,对其毒理研究取得了进展。已发现我国醉马草 (Achnatheruminebrians)对家畜的毒性与内生真菌的侵染有关。内生真菌侵染增加可使禾草对 42种害虫的抗性 ,并可增加对某些线虫和病害的抗性。与不带菌禾草相比 ,带菌禾草的另一特点是抗逆性强 ,牧草产量高。国际在该领域的研究主要集中在多年生黑麦草(L olium p erenne)和高羊茅 (Festuca arundinacea)。我国的研究发现 ,带菌布顿大麦草 (H ordeum bodg anii)和圆柱披碱草(Elymus cylind ricus)的牧草产量分别增加 3 3 .3 %和 2 78.8% ,分孽数分别增加 13 6.8%和 84.5%。目前 ,国际研究的重点包括大规模开展内生真菌生物学与生态学特性的研究 ,创造不含对家畜有害毒素的有益禾草 -内生真菌共生体 ,培育带内生真菌的草坪草品种 。Neotyphodium (syn. =Acremonium) endophytes are a group of fungi which live for all, or at least a significant part of their life cycle asymptomatically within grass plant parts. Innumerable studies on graminicolous endophytic fungi have been carried out internationally in the fields of mycology, pasture agronomy, animal and plant sciences and veterinary science during the last 25 years. Research on endophytes started in the early 1990's in China. In this paper research progress on the grass-endophyte association both in China and overseas was reviewed and key areas for further study were suggested. Fourteen Neotyphodium species have been formally identified and reported from 23 genera of grasses in the world literature. Endophytes have been found in 13 genera and 25 species of forage grasses in native grasslands in China. Among these host plants, Descampsia, Hordeum and Leymus genera have not been reported as Neotyphodium hosts previously in the world literature. Endophytes produce alkaloids within the host plant, which are toxic to livestock, including cattle, sheep, horses and deer grazed on Neotyphodium infected grasses. It has been estimated that the livestock industry in the United States and New Zealand suffers more than 640 million US dollars in lost production annually due to the endophytes. Fortunately the mechanism of toxicity has been understood and the chemicals responsible for livestock toxicosis identified. It was found that the toxicity of drunken horse grass in China was related to endophyte infection. The effects of endophyte infection on drunken horse grass toxicity to livestock are being studied in a series of feeding trials. One of the most beneficial effects conferred by endophytes on their host grasses is the production of toxins and feeding deterrents which reduce insect grazing. About 42 insect species have been reported worldwide to be deterred or adversely affected by feeding on endophyte infected grasses. Another beneficial effect imparted to grasses by endophytes is tolerance to envi

关 键 词：禾草 内生真菌 共生体 草地农业系统 生态系统 真菌毒素 家畜 草坪草 

分 类 号：S181[农业科学—农业基础科学]