Physiological And Biochemical Responses Of Leaves Of Ziziphus Jujuba Var. Spinosa To Soil Moisture

Ziziphus jujuba var.spinosa is a excellent testing materials to study plant responses to drought which widely distributed, strong adaptability, very drought-tolerant. In order to show physiological mechanisms of adaptability to drought of Ziziphus jujuba var.spinosa ,we examined the effects of different soil moisture on the content of chlorophyll ,leaf water, soluble sugar, MDA, SOD, CATand other physiological and biochemical indices through the coating technology for the control of soil moisture content near its root system.Then the evaluating content of droght-resisitance was enriched further.It could offer scientific evidence for breeding, culture of droght-resisitance and culture in different area of Ziziphus jujuba var.spinosa.Results showed that:1. The date indicated that the content of chlorophyâ…¡under different soil drought. With the reduction of soil moisture,the content of chlorophyâ…¡reduced slowly; then, with the changes in soil moisture,the content of chlorophyâ…¡in leaves showed a illusion of re-water effect, an upward trend, and then gradually reduced; to the end of leaves reminded at a high rate of chlorophyâ…¡hold.2. When soil water content of Ziziphus jujuba var.spinosa at 6%,the relative water content and absolute water content of Ziziphus jujuba var.spinosa keep at 80% and 63%yet. While natural water saturation deficit still maintained at a low level,Lower than any other dry plants, indicating Ziziphus jujuba var.spinosa has a strong drought resistance.3. Continuing drought lead Ziziphus jujuba var.spinosa leaf osmotic potential, water potential was "W"-type downward trend of treatment group,as well as control group. Ziziphus jujuba var.spinosa has small water potential and osmotic potential.The water potential and osmotic potential of treatment group during the experiment were maintained at -0.63Mpa,-0.13Mpa level.4. The changes of the content of free proline and soluble sugar with the extension of processing time has the same trend. compared with control, treatment group was 1.3,1.2 times the average. Osmotic and adjustive matter,for example:soluble sugar content and proline content increased can reduce the osmotic potential to maintain growth, so that Ziziphus jujuba var.spinosa with a low water potential and drought characteristics.5. Soil moisture on membrane injuried and activity of enzyme in Ziziphus jujuba var.spinosa leaves. Results showed that with the decline in soil water content, cell membrane injury, cell membrane permeability increases, conductivity increases, and MDA were increased, with the strengthening of activity of protective enzymes, membrane lipid peroxidation decreased, then, MDA content and electrical conductivity declined sharply, to the late experiments, protective enzyme activity is reduced, leading to increased accumulation of reactive oxygen species, making film increased lipid peroxidation, MDA content increased, membrane permeability increased.6. With the extension of processing time, Ziziphus jujuba var.spinosa showed the variation tendency of falling after rising ,such as SOD,POD,CAT, but the change laws of three kinds of enzymes were different to some extent.7. As the degree of drought stress intensified and time of drought stress prolonged to restrain more water, activity of NRA in Ziziphus jujuba var.spinosa leaves of treatment group showed the variation tendency of falling after rising , then falling.