Relationship Between Photosynthetic & Water Physiologic Characteristics And Individual Developmental Stage Of Populus Euphratica

Populus euphratica as an excellent tree species,in the desert in a wide range of survival and growth,drought is very strong,is the most favorable species against desertification.In this paper,the temporal and spatial characteristics of the morphological changes,photosynthetic water physiology and physiological and biochemical characteristics of Populus euphratica in different diameters(time)and different diameters(spatial levels)of Populus euphratica were studied in order to reveal the individual development of Populus euphratica Process of growth adaptation mechanism,draw the following conclusions:(1)The relationship between the morphological characteristics of the ectopic leaf of Populus euphratica and the individual developmental stages.The results showed that the leaf width and average leaf area increased gradually with the increase of the diameter,and the leaf shape index and leaf length decreased gradually.With the increase of the sampling height,Width,leaf area gradually increased,while the leaf length and leaf shape index is gradually reduced.With the increase of the diameter,the leaf dry weight and specific leaf weight increased gradually.With the increase of the sampling height(from the base to the top),the leaf dry weight and leaf weight of the leaf were gradually increased.The correlation analysis also showed that leaf length and leaf shape index of leaf of Populus euphratica decreased with the increase of sampling height,leaf width,leaf area,dry weight and specific leaf weight increased with the increase of sampling height.(2)The relationship between the photosynthetic characteristics of photosynthetic water and the developmental stages of Populus euphratica.The net photosynthetic rate,transpiration rate,stomatal conductance and carbon isotope values of the leaves increased gradually with the increase of the sampling height,and the intercellular CO2 concentration of the leaves decreased gradually.The correlation analysis showed that the net photosynthetic rate,intercellular CO2 concentration and stomatal conductance of the leaves were closely related to the height of the leaves,ie,the net photosynthetic rate and stomatal conductance of the leaves were positively correlated with the height of the leaves,There was a significant negative correlation between the intercellular CO2 concentration and the height of the leaves in the leaves.The correlation coefficient between the carbon isotope values and the net photosynthetic rate was 0.56,which was positively correlated with the stomatal conductance of-0.55,Related.The changes of net photosynthetic rate and stomatal conductance were closely related to the changes of leaf shape and leaf shape index,while the intercellular CO2 concentration was closely related to the change of sampling height.(3)Physiological and Biochemical Characteristics of Populus euphratica Leaves and Their Relationship with Individual Development.The soluble sugar content of the leaves increased gradually with the increase of the diameter,and the soluble protein content of the leaves decreased gradually with the height of the leaves.The contents of proline and malondialdehyde(MDA)in the leaves increased with the increase of the height of the leaves.Leaf soluble protein and proline content were closely related to the height changes of leaves in the leaves.The leaf proline content increased with leaf width and leaf area,and the content of soluble protein and proline Leaf morphology and the height of the tree where the alien leaves are closely related,which means that the broad-leaved leaves or oval leaves of Populus euphratica have stronger resistance to stripes or lanceolate.