Abstract:

Eremochloa ophiuroides was used to study the effects of acid rain stress on chlorophyll fluorescence characteristics.The results showed that maximal photochemical efficiency of PSⅡ(F_v/F_m),potential activity of PSⅡ(F_v/F₀),photochemical quenching(q_P),quantum yield of PSⅡ electron transport(Φ_PSⅡ),electron transport rate of PSⅡ(ETR),non-photochemical quenching(NPQ)in leaves were reduced after 6 h stress with acid rain.The decline of above parameters in treatment with pH 2.5 were faster and larger than that with pH3.0.F_v/F_m、F_v/F₀、q_P、Ф_PSⅡ、ETR、NPQ in treatment began to be gradually recovered after the treatment ended for 24 h,and up to the level of control after the treatment ended for 48 h.The results also demonstrated the potential use of this fast and noninvasive techniques——chlorophyll fluorescence to screen for different acid rain tolerant genotypes and to detect the physiological response of grasses to different environmental factors.

Key words: simulated acid rain, Eremochloa ophiuroides, chlorophyll fluorescence