内生真菌感染对宿主植物高羊茅锌耐受性的影响

以感染内生真菌(Neotyphodium coenophialum)和未感染内生真菌的高羊茅(Festuca arundinacea Schreb.)为实验材料,在营养液中加入ZnSO4进行锌胁迫实验,分析内生真菌对宿主植物锌耐受性的影响。与未感染内生真菌的植株相比,内生真菌感染对高羊茅的总生物量没有显著增益作用,但增加了分蘖数和叶片延伸生长累积值。内生真菌感染降低了高羊茅中Zn2+的总含量,改变了锌在高羊茅中的分配,增加叶鞘中锌的含量,减少叶片中锌的含量。在高锌浓度下,内生真菌感染对净光合速率的变化没有影响,但是显著提高了其宿主的PSⅡ光化学效率(Fv/Fm)。总体来看,内生真菌感染改善宿主高羊茅的锌耐受性。

Effect of endophyte infection on Zn resistance of tall fescue

The effect of Zn on tall fescue (Festuca arundinacea Schreb.) infected with or free from Neotyphodium coenophialum was studied by addition of ZnSO4 to the nutrient solution to analyse the effect of endophyte infection. Compared with the endophyte|free tall fescue, endophyte infection did not improve the total biomass of tall fescue, but the symbiotic plants showed higher values of tiller number and cumulative leaf length. The presence of the fungus in the plant led to a limitation of the total Zn concentration and modified the pattern by decreasing the Zn concentration in leaves and increasing the Zn concentration in sheaths. Under high Zn stress, the alleviation of negative effect on net photosynthetic rate was not shown, but endophyte infection increased photosystem II (PSII) activities. In conclusion, endophyte infection had a beneficial effect of Zn stress on the host tall fescue.