The Research Of Physiological Characteristics Of Drought Resistance About Wild Cherry Plum

In this paper, study on seedling cultivation of wild cherry plum (Prunus divaricata.Ldb), through the natural soil drought seedling Terada and three different plants of Prunus divaricata17d, osmotica determination, reactive oxygen species, the protection of enzymes indicators to explore drought means about the Prunus divaricata in the soil of natural drought conditions , compared on Terada with the drought tolerance size; through three kinds of water (SRWC70~75%, 45~50%, and 30~35% ) to deal with potted seedlings of Prunus divaricata measured Pn, WUE, osmotica, active oxygen content, MDA content of the protection of enzymes, analysis of Prunus divaricata mechanisms to resist drought stress; the use of paraffin sections were observed in field and pot leaves of Prunus divaricata changes in microstructure, from the aspects of the structure of Prunus divaricata for drought stress adaptation mechanisms. The main findings are as follows:â… . With the aggravation of soil drought stress, the relative of proline content, soluble sugar content and plasma membrane permeability of Terada and three different Prunus divaricata were increasing, soluble protein content was decreasing. But there differences of change between different single plant. On 17th days of soil drought stress,proline and soluble sugar content,activity of antioxyenic of Prunus divaricata were the most highest.Besides,H2O2 and MDA were the more lowest ;and relative plasma membrane permeability and protein were the most stable,so Prunus divaricata had most drought resistance. The soil drought resistance of Terada was weaker than that of prunus divaricata.â…¡. Wild cherry plum (Prunus divaricata.Ldb) seedling pot experiments that deal with three kinds of water 20d, normal moisture and moderate drought stress to deal with double-peak curve of Pn showed severe drought stress to deal with as a single peak curve, WUE trends and the basic synchronization Pn; normal water and in to deal with severe drought stress, the stomatal limitation is the main reason for the decline in photosynthesis, and to deal with severe drought stress, non-stomatal limitation of photosynthesis is the main reason for the decline. Three kinds of processing 1 ~ 30d, Wild Cherry Plum body proline, soluble sugar, K + content showed an upward trend in soluble protein content decreased, with increased drought stress in soil, so that H2O2 content increased, At the same time, SOD, POD, CAT activity is also enhanced; 30d severe drought stress, although the mobilization of a large number of osmolyte accumulation, but the protection of CAT and POD enzyme 20d in dealing with the rapid decline after the highest, when the 30d and lower than the stress to a minimum Initially, that this enzyme has been unable to remove an excessive amount of H2O2, the end, the MDA, the relative permeability of the plasma membrane of high-speed increase, even after the lifting of water stress and treatment of complex 1d there are significant differences (p <0.01), thus leading to destruction of membrane structure , membrane permeability increased, exacerbated by membrane lipid peroxidation, leading to membrane injury, further clarification of wild cherry plum 30d can not tolerate severe drought stress; moderate drought stress to deal with 30d, Wild Cherry Lee osmotica in vivo and protect the enzyme system the combined effect of a positive response to enable plants to maintain the dynamic balance, rehabilitation of water content after the MDA deal to return to the level of 1d, the medium for resisting drought stress on plant damage.â…¢. Soil drought on the fields of natural and wild cherry plum seedling leaves Terada microstructure impact study found that the field of Prunus divaricata leaves, in the water after the 3d to 17d, palisade tissue and spongy tissue changes in some, but not significantly; the cells during the same period structure that the palisade tissue / spongy tissue ratio and CTR value are Prunus divaricata > Terada, note the structure of Prunus divaricata than the drought is Terada; potted Prunus divaricata leaves under drought stress in moderate 20d, mesophyll cells tend to fence, and severe drought stress significantly mesophyll thickening at 20d, palisade tissue thickness, to adapt to changes in moisture.