Abstract: Cerasus sachalinensis seedlings were used as test materials to study their photosynthesis and chlorophyll fluorescence under effects of seven Cerasus species leaf aqueous extracts. After treated with the aqueous extracts of C.sachalinensis, C. fruticosa, C. pseudocerasus, Colt, and C. avium, the se
edlings leaf chlorophyll a content, chlorophyll a/b ratio, net photosynthetic rate(P_n), stomatal conductance (G_s), intercellular CO₂ concentration (C_i), maximum photochemical efficiency of PSⅡ (F_v/F_m), and quantum efficiency of noncyclic electron transport of PSⅡ (Φ_PSⅡ) decreased, while the carotenoid content, F₀, and nonphotochemical quenching coefficient (_qN)  increased, illustrating that the leaf aqueous extracts of these five Cerasus species had negative effects on the photosynthesis of  C. sachalinensis. Among the five aqueous extracts, the extract of C. sachalinensis had more obvious impact, suggesting its stronger autotoxicity. On the contrary, the aqueous extracts of Gisela and C. mahaleb had definite promotion effects on the photosynthesis of C.sachalinensis.

Key words: Leymus chinensis grassland, Soil, Total iron, Available iron