醉马草内生真菌对其伴生种硬质早熟禾和针茅生长的影响

Effects of Achnatherum inebrians infected with Neotyphodium endophyte on accompanying species of Stipa capillata and Poa sphondylodes

本研究以我国西北部的天然草原广泛分布的烈性毒草醉马草和其主要伴生种针茅、硬质早熟禾为供试材料,研究内生真菌侵染的禾草与其他禾草的竞争作用。结果表明,带菌(E+)醉马草抑制了针茅、硬质早熟禾种子的萌发和幼苗的生长,发芽率分别下降了17.1%和13.6%,胚芽长分别降低了23.2%和16.3%;带菌(E+)醉马草对针茅、硬质早熟禾的株高均有显著的抑制作用(P<0.05),从发芽后第1周便显著抑制了2种供试禾草的生长;在与醉马草混种时,带菌(E+)醉马草对针茅和硬质早熟禾的分蘖数以及单株生物量均有显著的抑制作用(P<0.05)。不带菌(E-)醉马草对2种供试禾草以上的各项指标均没有产生显著的影响(P>0.05),且针茅、硬质早熟禾对醉马草没有显著影响(P>0.05)。综上所述,带菌(E+)醉马草对针茅和硬质早熟禾有强烈持续的竞争抑制作用,而不带菌(E-)醉马草则对2种禾草没有显著的影响。

Drunken horse grass（Achnatherum inebrians）,an intoxicating grass in native grasslands of Northwest China,often grows in conjunction with Stipacapillataand Poa sphondylodes.Competitive interactions between endophyte infected（E＋）A.inebrians and endophyte free（E-）A.inebrians with S.capillataand P.sphondylodes were investigated.E＋A.inebrians had a significant inhibition effect on percentage seed germination and seedling growth（P〈0.05）,which declined significantly by 17.1%,13.6%,respectively.Similarly,seedling length declined 23.2%and by 16.3%;E＋ plants had significant inhibition effects on tiller heights of S.capillataand P.sphondylodes from the first week after germination（P〈0.05）and on tiller numbers and total biomass（P〈0.05）.E-A.inebrians had no significant effects on seed germination,seedling growth,tiller height,tiller number or total biomass（P0〉.05）.S.capillataand P.sphondylodes had no significant effects on A.inebrians.In summary,E＋A.inebrians showed significant antagonism to S.capillataand P.sphondylodes,but E-A.inebrians had no significant effects on the other two grasses.