A study on diurnal variation of photosynthesis in four Populus strains

The selection of species(strain) and the development of cultivation measures is an important part for establishing farmland shelterbelt.In this study,we selected four Populus strains('I-69'、'I-72'、'I-63' and 'Nanlin 895'),which have been widely planted in the Huaihe River,to analysis their photosynthetic characteristics.The results showed that: Whether maximum net photosynthetic rate in a day or daily average net photosynthetic rate,The photosynthetic capacity in four strains could be arranged from high to low as: 'Nanlin 895''I-69''I-63' 'I-72'.This indicated that 'Nanlin 895' had strong photosynthetic capacity compared with other strains;Concerning the impact of physiological and ecological factors on photosynthesis,the net photosynthetic rate of four strains had a certain correlation with the transpiration rate,intercellular CO2 concentration,leaf surface temperature and stomatal conductance.Among them,the most significant factor was transpiration rate,the next was leaf surface temperature.The influence of intercellular CO2 concentration and stomatal conductance was relatively small.Through the analysis of photosynthetic and physiological characteristics,a theoretical basis for the construction of farmland shelterbelt along the Huaihe River was provided.