Abstract:The photosynthetic functions of soybean were obviously improved by pretreatmentwith potassium 2,3-epoxypropionate,an inhibitor of photorespiration.Thephotosynthetic rate,capacity of transfer of light energy from light-harvesting chlorophylla/b-protein complex(LHCP)to Photosystem Ⅱ(PSⅡ)and efficien