[Objective] The aim was to research the effects of N, P and K fertilizers on photosynthetic characteristics of mulberry. [Method] In the test, Chuan 826, a va- riety of mulberry, was taken as an example to explore the relationships of chloro- phyll content, leaf area index, net photosynthetic rate, stomatal conductance of leaf, CO2 concentration of cells in leaves and transpiration rate with N, P and K fertilizers at different quantities. [Result] N, P and K fertilizers at different quantities have ef- fects on photosynthetic indices. In detail, N, P and K fertilizer at appropriate quanti- ties enhanced LAI, Chla＋b, Pn, Cond and Tr, Ci of mulberry leaves in control group without fertilizers was significantly higher than that in treatment groups. N, P and K at proper quantities （N at 600 kg/hm2, P at 210 kg/hm2 and K at 300 kg/hm2） would keep functional leaves well and higher photosynthetic period for a long term. [Conclusion] The research explored adjustment of photosynthetic characteristics and differ- ent treatments on photosynthesis of mulberry, providing reference for construction of excellent and highly-qualified mulberry garden.
