During the primary growth stage of winter wheat in Middle Yunnan Plateau, atmosphere temperature isusually above 5℃. Wheat could continually grow harmony with higher photosynthesis and dry matter accumulation. LAI continually increased. The wheat community had a high rate of vegetative growth. During the late growth stage of wheat (from April to May), daily maximum temperature was lower than 27'℃ Wheat grain filling stage lengthened as no high temperature harmfully affacted on leaf photosynthetic function. ...