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The of Aridification has become the focus of global attention, plants of arid habitats adaptation mechanism and Drought nature of research has become one of the important topics of plant physiological ecology research. Seedlings and the following year mowing Amorpha potted the Health Amorpha as experimental materials, by human control soil water content, study the impact of drought stress and several of its physiological and biochemical indexes. The results showed that: 1. Amorpha seedlings under moderate drought conditions can be normal, good growth, the excessive drought inhibit the normal growth and development, and specific performance for plant height and leaf area growth was inhibited, and each index The degree of inhibition of stress intensity and stress long. The heavier stress level, the longer the stress, significant inhibition. With the intensification of drought stress, Amorpha seedlings net photosynthetic rate (Pn), transpiration rate (Tr), stomatal conductance (Gs) decreased water saturation deficit (WSD), water use efficiency (WUE) superoxide dismutase (SOD) activity, the activity of superoxide dismutase (POD), K content of soluble sugar and free proline content significantly increased; chlorophyll a, chlorophyll b, total chlorophyll, carotenoid content gradually increases with decreasing soil water content, chlorophyll a / chlorophyll b no significant change. These physiological indicators the trend reflects Amorpha seedlings arid environment adaptability, its ability to withstand drought stress a positive adjustment mechanism. 3 different soil relative water content, water potential of the Amorpha stem water potential and root showed significant reaction. Adequate moisture and moisture extreme deficit, stem water potential difference of 2.83 MPa, root water potential difference of up to 3.84 MPa; Amorpha stem water potential and reduced root water potential and soil water potential gradient that soil water supply capacity is closely related. With the intensification of drought stress, soil, root, stem water potential were decreased, 35% treatment difference of 2.96 MPa water potential between the soil and the root than other water treatment slightly increased, indicating Amorpha seedling growth, by increasing the potential difference between the roots and the soil in the lower moisture content of the soil to improve its water absorption capacity. Drought stress impact of the Amorpha various physiological and biochemical characteristics with a certain degree of difference. General, the greater the intensity of drought stress, the more significant the impact of each indicator. In this study, Amorpha leaf the physiological indicators transpiration rate, water use efficiency and biochemical indicators of free proline content of soluble sugar and K, the activity of SOD and POD, root and stem water potential can objectively reflect the seedlings under drought stress adaptability, as drought resistance identification indexes. Comprehensive analysis of the above indicators Amorpha under drought stress indicators responded well to show some adaptation characteristics, with strong drought resistance, suitable for cultivation in the arid zone. In desertified areas of drought, sandy wasteland, arid sloping fields and dry and barren mountain can be vigorously promoted the planting Amorpha.
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