Abstract: Taking cut flower chrysanthemum ‘Baima’ as test material, a pot experiment was conducted to study the effects of controlled-release fertilizer on the leaf chlorophyll fluorescence parameters, chlorophyll and nutrient contents, and ornamental quality of chrysanthemum. Under no fertilization, the maximal photochemical efficiency of PSⅡ in dark (F_v/F_m), potential photochemical efficiency of PSⅡ (F_v/F_o), and quantum yield of PSⅡ electron transport (Φ_PSⅡ) decreased significantly, compared with those under fertilization. With the application of conventional compound fertilizers CCFA (N：P：K=20：8：10) and CCFB (N：P：K=14：14：14), the F_v/F_m, F_v/F_o and Φ_PSⅡ had a slight increase in early period (30-60 d) but a remarkable decrease in mid and later periods (75-120 d), compared with those under the application of controlled-release fertilizers CRFA (N：P：K=20：8：10) and CRFB (N：P：K=14：14：14). Under the application of CRFA, the F_v/F_m, Φ_PSⅡ, and photochemical quenching (q_P) had somewhat increase, as compared with the application of CRFB. The non-photochemical quenching (NPQ) under the application of CRFA and CRFB decreased significantly, compared with that under the application of CCFA and CCFB and the control. The chlorophyll content had a similar change trend with F_v/F_m, F_v/F_o , and Φ_PSⅡ. The leaf N, P, and K contents, flower stalk length and stalk diameter, flower diameter, and flower fresh and dry mass at harvest stage all increased under the application of CRFA and CRFB,compared with those under the application of CCFA and CCFB and the control, and the flower fresh and dry mass was significantly higher under the application of CRFA than of CRFB. This study showed that controlled-release fertilizer could improve the ornamental quality of chrysanthemum via improving the leaf chlorophyll content, photochemical transduction rate, and nutrient uptake, and CRFA had better effects than CRFB.

Key words: soil physical and chemical property, freeze-thaw, chrysanthemum, controlled-release fertilizer, chlorophyll fluorescence, nutrient, ornamental quality, wind erosion, water erosion.