不同水分条件下丛枝菌根真菌对刺槐生长和光合特性的影响

摘要

研究了正常供水和水分胁迫条件下接种丛枝茵根真菌(arbuscular mycorrhizal fungi,AMF)根内球囊霉(Glomus intraradices)和摩西球囊霉(G.mosseae)对刺槐(Robinia pseudoacacia)生长和光合特性的影响.结果表明:2种水分条件下,接种AMF提高了刺槐的株高、地径、地上和地下干重.正常供水条件下接种AMF,刺槐的水分利用效率显著提高,净光合速率和蒸腾速率等变化不大.水分胁迫条件下接种AMF,刺槐的净光合速率、气孔导度、胞间CO2浓度、蒸腾速率、最大荧光、Fv/Fm和qP显著提高,水分利用效率降低.2种水分条件下接种AMF通过不同的机制促进刺槐生长.在正常供水时接种AMF可提高刺槐的水分利用效率促进其生长,在水分胁迫时接种AMF可提高刺槐的光合作用水平促进其生长.%Effects of two arbuscular mycorrhizal fungi (Glomus intraradices and G.mosseae) on the growth and photosynthetic characteristics of Robinia pseudoacacia under different water conditions (well watered and water stressed) were studied.The results revealed that arbuscular mycorrhizal fungi (AMF) increased plant height,ground diameter,dry mass of the shoot as well as dry mass of the root of R.pseudoacacia under both well watered and water stressed conditions.Under well watered condition,AMF notably increased water use efficiency,while photosynthetic characteristics such as net photosynthetic rate and transpiration rate were not influenced.Under water stressed condition,AMF significantly increased net photosynthetic rate,stomotal conductance,intercellular CO2 concentration,transpiration rate,Fm,Fv/Fm as well as qP,while water use efficiency was decreased.It was concluded that AMF promoted the growth of R.pseudoacacia via different mechanisms under different water conditions.Under well watered condition,AMF boosted growth of R.pseudoacacia by increasing water use efficiency as improving photosynthesis under water stressed condition.