Effects Of Drought Stress On Morphological And Anatomical Structure And Proteins Of Young Assimilating Branches Of Tamarix Hispida Willd.

Tamarix hispida Willd. belongs to Tamaricaceae Tamarix L.. It posseses good capacities of salt tolerance, sand fixation, drought resistance, and temperature tolerance with great vitality, therefore, carrying on research to drought-resistant features and physiological mechanisms of Tamarix hispida Willd. has very important practical significance of plant selections, which not only for water saving and windbreak but also sand fixation in China. This paper takes cutting branches of two years old Tamarix hispida Willd that grown on Section Kaerdayi at Tarim River lower reaches as experimental materials, and makes relatively systematic analysis and descriptions on their young assimilating branches and leaf for anatomical structures, cytomorphology, cellular tissue chemistry, and specific protein.The results showed that Tamarix hispida Willd. has typical adaptabilities for drought. As for the assimilating branches there are cuticle in the epidermis, dense epidermal hairs, relatively small stomata with substomatic chamber, multilayer cortical cells with assimilation efficiency, conductive tissue well developed, and small pith area. Meanwhile, the leaf has greater leaf thickness, compact palisade tissue on abaxial side. Under drought condition the starch and chloroplast obviously reduced comparing with the control in the assimilating braches and the leaves. Moreover, in the leaf, intercellular space increased obviously, palisade tissue became thinner and sparser.Using two-dimensional electrophoresis of protein and image analysis system, the whole proteins in leaf of Tamarix hispida Willd. under drought stress were studied. There were six proteins decreased and then disappeared with the intensification of the stress, and appeared again after the rehydration[a1(20KD, PI 7.26),a2(20KD, PI 6.74),a3(21KD, PI 6.30),a4(23KD, PI 6.76),a5(27KD, PI 5.23),a6(31KD, PI 7.25)]; one protein disappeared gradually under drought stress without appearance after rehydration[b(21KD, PI7.51))]; one protein appeared under the drought stress and weakened after rehydration[(23KD, PI7.04)]. Proteins a1~a6 probably related to drought stress with recovery after rehydration. Protein b disappeared permanently probably because that the drought stress exceeded the threshold Tamarix hispida Willd. can endure and caused permanent damage. Protein c is the drought-induced protein generating as Tamarix hispida Willd. subjected to drought stress, and it played an important role when Tamarix hispida Willd. adapted to drought.