Diurnal Variation Characteristics of Cotton Photosynthesis under Different Soil Moisture Conditions

This experiment adopts the CB-1102 photosynthetic apparatus to monitor the diurnal change of cotton photosynthesis under different water conditions.Through the test data analysis,the following conclusions are obtained:1cotton plant photosynthetic active radiation is affected by the degree of cloud cover and has no relation with the soil moisture content;2 curves of net photosynthetic rate,transpiration rate and stomatal conductance show double peaks,moreover,the relationship between the peak value and soil moisture is positively related;3intercellular CO2 concentration curve shows left-leaningVshape and has a close relation with soil moisture.The research on cotton canopy leaf photosynthetic diurnal variation under different soil water conditions can improve the field water use efficiency to achieve the goal of high efficiency water saving,and has important guidance for cotton planting in the southern Xinjiang,which is an extreme water-lack area.