摘要
研究了内蒙古中东部草原3个不同样地(羊草、西乌旗和霍林河)中Neotyphodium内生真菌的侵染对宿主羽茅(Achnatherum sibiricum(L.)Keng)种群光合生理特性的影响,结果表明:自然条件下,羊草样地和西乌旗样地染菌(E+)羽茅植株的净光合速率(Pn)显著高于不染菌(E-)羽茅,说明E+羽茅植株具有更高的同化能力,而霍林河样地中二者差异不显著;3个样地中Neotyphodium内生真菌对宿主羽茅的蒸腾速率、气孔导度、光能利用效率、水分利用效率均无显著影响;引起羽茅植株午间Pn降低的主要原因是非气孔因素,与是否染菌没有必然联系;光响应曲线拟合结果表明Neotyphodium内生真菌对宿主羽茅的表观量子效率、最大净光合速率、暗呼吸速率、光补偿点和光饱和点没有显著影响。
We assessed how Neotyphodium infection influenced the photosynthetic characteristics of three natural populations of Achnatherum sibiricum, one of the main resources of forage in Inner Mongolia Steppe. We used the Licor-6400 apparatus to measure the parameters including photosynthetic rate （Pn）, transpiration rate （Tr）, stomatal conductance （Gs） and intercellular CO2 concentration （Ci ）. Some environmental parameters such as photosynthetic available radiation （PAR） and air temperature （ Ta ） were automatically recorded. We also ob- tained the light response curve under a gradient of controlled PARs. The results showed that in Leymus chinensis plot of the IMGERS-CAS population and Xi Ujimqin Qi population, the diurnal average photosynthetic of E ＋ plants were significantly higher than those of E - plants, but in Hulingol population the difference was not significant. The effect of Neotyphodium on photosynthetic might have some correlation ship with the water condition of the local habitat. In lower water availability habitats, the endophytes tended to increase the photosynthetic ability of the host plants, while in higher water availability habitats, the endophytes had no significant contribution. In each population, the Tr, Gs, Ci, LUE（ light use efficiency） and WUE（ water use efficiency） were not signifi cantly different between E ＋ and E - plants. The decrease of mid-day Pn was caused by non-somatal factors, and has nothing to do with the endophytic infection.
出处
《植物研究》
CAS
CSCD
北大核心
2009年第1期61-68,共8页
Bulletin of Botanical Research
基金
国家重点基础研究发展规划项目(2007CB106802)
国家自然科学基金项目(30770348)
天津市自然科学基金项目(06YFJMJC11600)
