Study Of PEG Induce Water Stress On Plant Growth And Physiological And Biochemical Characteristics Of Several Ground Cover Plants

Such as Hemerocallis fulva, Iris tectorum Maxim, Ophiopogon japonicus cv., Reineckea carnea, Mentha canadensis L., are several common garden plants, wilding applied in a wide range of landscaping.In this experiment, these types of gardening in plant material, from the appearance of morphological, physiological and biochemical indicators of their biological response under PEG is aimed at building Drought index system of these ground cover plants for screening drought resistance, water gardening in small plants species, to provide scientific and practical methods,laying a foundation for breeding drought,drought gardening for plant germplasm resources development,popularization and application of a more scientific basis.The main conclusions are as follows:1. Drought injury index observation leaves and root activity that PEG stress, day lily, Iris tectorum Maxim, ophiopogon, Reineckea carnea, Mentha canadensis L., among the five plants, Mentha canadensis L. treatment 4 days,30% PEG concentration of plant death,16 days 20% PEG treatment concentration of plant death,21 days as they deal with Mentha canadensis L.10% -30% concentration of plants treated with no new roots emerged, and most of the old root rot and death, there is no measure of its root activity,minimal impact on drought damage grass along the street address within 21 days, part of the leaves dry, shrink, its root activity first increased in the downward trend in the concentration of 20% PEG stress peaked, then decreased slowly.Drought injury index in leaves and root activity, based on the conclusion: five to be drought-resistant plants in the strongest Ophiopogon japonicus cv., while the Mentha canadensis L. weakest.2. PEG stress on several gardening ground cover leaf morphology study shows that: Mentha canadensis L.wilt is most serious, large changes in leaf length leaf width; Hemerocallis fulva and auspicious times; Ophiopogon japonicus cv.affected Mentha canadensis L.3. PEG stress on several ground cover plant chlorophyll content of that:as the stress intensifies, some to be the chlorophyll content of plants have shown a sharp downward trend, and at the highest concentration of chlorophyll content when compared to the control there were very significant difference. Hemerocallis fulva most affected photosynthesis, the most sensitive to water stress, followed by auspicious grass; the Iris tectorum Maxim is more sensitive to water stress; Ophiopogon japonicus cv.photosynthesis under drought stress affected the smallest, the least sensitive to water stress, anti- early is strong.4. PEG stress on osmotic adjustment of research shows that: Ophiopogon japonicus cv. of free proline and soluble sugar content in the rate of increase is greater than Iris tectorum Maxim, day lily and auspicious grass, and ophiopogon in the CK levels of free proline and soluble sugar content was significantly higher than other three kinds of ground cover plants.5. PEG stress on the cell membrane permeability and active oxygen metabolism that:Leaf cells of four to be compared with the control of electrolyte leakage had increased, and Ophiopogon japonicus cv., Iris tectorum Maxim, Reineckea carnea compared Hemerocallis fulva degree of membrane permeability suffer the most, while the SOD activity of complex Ophiopogon japonicus cv. under drought stress damage its ability to withstand strong reactive oxygen species, and reactive oxygen species of Hemerocallis fulva injury against the weakest.The change of MDA content, analysis of variance showed that Hemerocallis fulva in different times and different concentrations of MDA were significantly higher than the control, MDA content increased the rate of Hemerocallis fulva significantly higher than the other three plants, so their ability to tolerate drought stress minimum.6. Using obtained principal component analysis Hemerocallis fulva, iris, Ophiopogon japonicus cv., Reineckea carnea four kinds of luck being the first principal component of plant chlorophyll content, proline content, soluble sugar content, leakage rate, MDA content;The second principal component is the root activity and SOD activity.7. The principal component analysis and subordinate function analysis, the four kinds of ground cover plants drought capacity from strong to weak in the order: Ophiopogon japonicus cv.> Iris tectorum Maxim> Reineckea carnea> Hemerocallis fulva,This conclusion and the four kinds of ground cover plants in the form of PEG stress and physiological and biochemical characteristics consistent performance.