Physiological response and shading tolerance evaluation of Sauropus androgynus in different planting environment
In order to explore the effects of different planting environments on the physiological characteristics of Sauropus androgynus(L.)Merr.,and to evaluate its shade tolerance,the 3-year-old cutting seedlings of Sauropus androgynus were planted in three envi-ronments:Outdoor(100%light intensity),underwood(65%light intensity)and greenhouse(30%light intensity)planting.The pho-tosynthetic pigment content,instantaneous photosynthetic characteristics and osmotic adjustment substance content of Sauropus an-drogynus leaves under different environments were determined.The results showed that the contents of chlorophyll a and chlorophyll(a+b)of Sauropus androgynus in underwood and greenhouse planting were significantly higher than those of outdoor planting;with the increase of shading degree,the net photosynthetic rate of leaves increased first and then decreased,and reached the highest in under-wood planting,while stomata conductance,intercellular CO2 concentration and transpiration rate showed outdoor planting>under-wood planting>greenhouse planting,and gradually decreased with the increase of shading degree.The content of soluble sugar and soluble protein increased first and then decreased with the increase of shading degree,and reached the maximum in underwood plant-ing;the contents of free proline and MDA decreased with the increase of shading degree,and reached the maximum in outdoor plant-ing.The results of membership degree analysis showed that the photosynthetic and physiological status of Sauropus androgynus plants was the best in underwood planting,and the too strong or too weak light environment was not suitable for their growth.
万方数据
维普
