Study On Cold Resistance On Two Kind Of Camphor Tree Seedings In Natural Decreasing Process Of Air Temperature

In this study, the2011spring sowing in Henan Agricultural Universityexperimental nursery base year Cinnamomum bodinieri and Cinnamomum camphorseedlings as materials, changes of Cinnamomum bodinieri and camphor in2011-2012year in winter and cool in the process of physiological and biochemical indexes weremeasured,the and its hardiness strength of the specific analysis and comparison. Theresults are as follows:(1) In the natural cooling process, Low temperature on two kinds of testedcamphor leaf cell membrane caused by different degrees of membrane damage.Leaves the relative conductivity and MDA content along with the arrival of cold airagain and again elevated temperatures plunged in early November, Respectively,maximum average temperature in January and early2reached the lowest value.Throughout the test, electrical conductivity and MDA content in the leaves of thesame period test were lower than that of Cinnamomum camphora, the damage to thecell membrane to a lesser extent, cold resistance ability is slightly stronger.(2) In the natural cooling process, the Cinnamomum plants,while cell membraneinjury, studies this experiment researched two response mechanism of Cinnamomumplants. Including: The one, adjusting the osmolyte. Free proline during cold protectionis an important material, But early effect slightly worse, reached the maximum valuein the middle of January, after the unusually cold spell in early spring rise again ofMarch; The accumulation of soluble protein in the cold air strikes continue to rise;there are two peaks, one is the continuous low temperature of a December February.Coordination among each other to maintain cellular osmotic balance, the changes byadjusting their content to adapt to changes in temperature, thereby reducing damage tothe cell membrane. Change of soluble protein and free proline content in leaves ofCinnamomum bodinieri and Cinnamomum camphora consistent All change trendpolyline type.Another is the protective enzyme system, lifting test and Cinnamomumcamphora leaves SOD, POD, CAT activity increased with the temperature changes have different degree,through the synergistic effect to reduce the intracellularaccumulation of free radicals and reactive oxygen species, defense system of its cellmembrane damage Increased antioxidant capacity, thus effectively againstlow-temperature cold. Comparative analysis of changes in enzyme activity of twokinds of camphor tree, the enzyme activity showed: strong cold resistance test wassignificantly higher than the same period of camphor, more conducive to resistance tolow temperature.(3) In the natural cooling process,the majority of fatty acid composition weremyristic acid palmitic acid, static acid, oleic acid, linoleic acid; Saturated fatty acidwith palmitic acid as main component, unsaturated fatty acid in linolenic acidaccounted for large numbers. In the camphor tree leaves, with decreasing temperature,increasing unsaturated fatty acid content is mainly caused by the increase of linolenicacid content.The leaves of camphor in the unsaturated fatty acid content and IUFA valuevaries with the seasons change regularly. Low temperature is favorable to theformation of unsaturated fatty acid and IUFA increase. The leaves of Cinnamomumbodinieri and Cinnamomum camphora in the unsaturated fatty acid content and IUFAvalue (index of unsaturation) trends and linolenic acid content and unsaturated fattyacid content of the same change trend, were increased first and then decreased.Through the comparative analysis of Cinnamomum bodinieri and camphorcontent of unsaturated acids and IUFA fatty worth, Strong cold resistance of the testitself has higher content of unsaturated fatty acid, IUFA value is higher and theamplitude of variation is relatively large, so the low temperature resistant threat. Coldhardiness of weak camphor, unsaturated fatty acid content is relatively small, thevalue of IUFA is relatively low, more sensitive to low temperature.(4) In this experiment the comprehensive analysis and comparison of the coldresistance evaluation index that: two kinds of camphor in the process of naturalcooling, there is difference between the physiological indices of cold resistance value,but basically the same trend. The results from the physiological and biochemical ofcold resistance in the process of natural cooling Cinnamomum bodinieri seedlings inCinnamomum camphora. Cinnamomum bodinieri>Cinnamomum camphora.