Abstract:Diurnal changes of photosynthetic rate(Pn) and transpiration rate(Tr) were measured using Li-6400 portable photosynthesis system to study the characteristics of physiological ecology of the apple trees in full fruit period under different soil management models.The relationships of photosynthetic rate(Pn) and transpiration rate(Tr) with environmental factors and physiological factors were analyzed by correlation analysis.Results showed that the diurnal changes of photosynthetic rate(Pn) presented the double-peak curve for clean tillage treatment and growing grass treatment.The diurnal changes of photosynthetic rate(Pn) in film mulching,straw mulching,and gravel mulching presented the one-peak curve.The diurnal changes of the transpiration rate(Tr) presented the one-peak curve.The relationships of photosynthetic rate(Pn) with photosynthetically active radiation (PAR),air temperature(Ta),and leaf temperature(Tl) were the quadratic curve.Photosynthetic rate(Pn) was significantly positively correlated with atmospheric relative humidity (RH) and stomatal conductance(Gs),respectively,and was significantly negatively correlated with intercellular CO2 concentration (Ci).The relationship of transpiration rate(Tr) with photosynthetically active radiation (PAR) was power exponent and with atmospheric relative humidity (RH),was the quadratic curve.transpiration rate(Tr) was significantly positively correlated with air temperature(Ta),leaf temperature( Tl),and stomatal conductnce (Gs),respectively,and was significantly negatively correlated with intercellular CO2 concentration(Ci).Photosynthetic rates(Pn) for gravel mulching and straw mulching were the highest and there were little difference in the average diurnal change of transpiration rate(Tr) under different soil management models.The photosynthetic characteristics showed a significant correlation with environmental factors and physiological factors,respectively.