Study On Cold Resistance Of Four Oleaceae Plants

In this paper, four kinds of resistance to cutting type Oleaceae species (Fontanesia fortunei Carr.LigustrumobtusifoliumSieb.et, ForsythiomandshuricaUyeki, Sytinga microphylla) in the physiological characteristics under low temperature stress for membrane permeability and lipid peroxidation, soluble protein and free prolinamide acid content, protective enzymes, soluble sugar, chlorophyll and leaf morphological and anatomical changes in the structure and other aspects of plant physiological characteristics of these four changes in a systematic study on the Changchun-based tree pruning resistant physiology to adapt to the cold resistance mechanisms, and the combination of subordinate function of four different cold tolerance of plants to conduct a comprehensive evaluation of cold resistance, the results show that:1. As the temperature decreases, the four values of relative conductivity of Oleaceae plants is rising, while the MDA content in the four plants showed a first increasing and then decreasing trend, probably post-treatment temperature, plants physiological mechanism occurring disorders. That the low temperature stress, reactive oxygen metabolism of four trees in the balance is destroyed, increased membrane lipid peroxidation, membrane damage and demonstrated lipid peroxidation is closely related.2. In the process of low temperature stress, the leaves of four tree species in the activity of protective enzymes are sensitive to low temperature, which increases with decreasing temperature, indicating that the enzyme activity has increased after exercise to meet the low-temperature environment. One cold and strong SOD activity in the leaves of plants are more sensitive to low temperature and relatively stable with temperature changes. Weak cold hardiness of tree species response to temperature change is more disordered. Increased SOD activity in leaves of plants tested is an important way to adapt to low temperature. Four plant protective enzymes are increased firstly and then decreased, SOD activity with low temperature sensitivity will be to reduce the low-temperature damage.3. Soluble sugar content as the temperature decreases, at first increasing and then decreasing, then increasing. Four plants, Plant cold hardiness and strong soluble sugar content was high, Fontanesia fortunei carr., and the weak cold hardiness of plant soluble sugar content is low, such as forsythia. Soluble protein content and free proline accumulation decreased with treatment temperature first and then decreased, and processing temperature dependence is very high..4. With the lower treatment temperature, the amount of chlorophyll a downward trend. Fontanesia fortunei carr. chlorophyll content in leaves early in the processing temperature to reduce the slow, even in the whole treatment period, the chlorophyll content decreased compared with the slow pace of the other three plants.5. Oleaceae leaf of four paraffin sections were observed, the results show Fontanesia fortunei carr pubescens than water wax and cuticle development, and these three plants developed than forsythia. CTR values in sequence and the SR value of the order from small to large is the same, to judge from the cold hardiness of this indicator is:sytingamicrophylla> Forsythiomandshuicauyeki>Fontanesia fortunei carr>ligustrumobtusifoliumsieb.etzucc. From four plant cuticle thickness and spongy tissue thickness on the order of the ratio of the thickness of upper epidermis and spongy tissue thickness and the ratio of the size of the order of certain differences, but there is one thing in common is the ratio of these two forsythia features are standard in the cold outside.6. On the seven species of cold-resistant ability to trim a comprehensive evaluation. Oleaceae were four plant cold tolerance:sytingamicrophylla>Forsythiomandshuicauyeki>Fontanesia fortuneicarr>ligustrum obtusifoliumsieb.etzucc. From various indicators and the correlation between the temperature difference between the description of four different cold hardiness of plants, plants that have their own set of complete response reaction against the outside cold, so cold tolerance for all indicators in the size of the correlation different plant cold sexuality is the result of multiple factors that control is not from a single indicator to determine the cold tolerance of plants.