| Stipagrostis pennata, belonging to tribe Poaceae, Stipagrostis Nees, it has ability of drought tolerance,wind–erosion tolerance, sand burying tolerance, is born in altitude300-800m where are the flowsand,dunes and sand ridges. Stipagrostis pennata is a pioneer species of the moving sands of the arid desertregion in China, mainly distributed in the Junggar Basin. Growth in the Junggar Basin of Xinjiang indifferent population of the southern margin of Stipagrostis pennata research material, using conventionaltabletting technology to study the cell characteristics, the analysis of the variation of different population ofStipagrostis pennata environment of soil physical properties and cell characteristicsprovide a theoreticalbasis as well as the impact of environmental change on the cell characteristics, in order to Stipagrostispennata in the cell trait. The main conclusions are as follows:(1)Stipagrostis pennata four plots covering the0-40cm profile, the average moisture content was lessthan4%, the dunes yin and yang of the bottom of the aquifer were higher than the same slope in the centraland top of a dune, as follows: its base> middle slope> the top of the hill, and the range were1.54%(Stipagrostis pennata coverage), and1.96%(empty); average bulk density were1.47g/cm~3,1.44g/cm~3,1.48g/cm~3and1.60g/cm~3; Bare soil organic matter under the cover of Stipagrostis pennata to empty wereincreased by17.98%,8.44%and40.90%, indicating that lower soil moisture under the cover ofStipagrostis pennata, but the improvement of the organic matter content is gathered at the root of the sandaround plant seeds of growth and development of a favorable external security; four samples under thecover of Stipagrostis pennata soil pH around8.5is alkaline, indicating that the soil under the cover ofStipagrostis pennata0-40cm depth range may be affected by wind erosion, sand composition has changedgreatly, with higher levels of saline-alkali soil components. Survey found that plant diversity, the littlecluster of Stipagrostis pennata, and young the Calligonum or Haloxylon appear, indicating that the two areclosely related, gathering seed from Stipagrostis pennata roots of sand and associated Calligonum seedlingsthat Stipagrostis pennata altruistic behavior, and this is Stipagrostis pennata promote the growth of otherdesert plants, one of the reasons of moving sands.(2)Samples were drawn at8:00-9:00in the morning, the environment of20°C using8-hydroxyquinoline pretreatment eight hours, the Kano fixative fixed12hours,1mol/L hydrochloric acidsolution from25minutes, the card Pomagenta dye staining two hours of the conditions for the optimalconditions of the Stipagrostis pennata pressure plate method.10sample points in different populations ofStipagrostis pennata apical staining was observed Stipagrostis pennata chromosomes are diploid,2n=22,the chromosome is highly compressed, stick together and poor dispersion of the microscope in a100-foldoil showing granular chromosomes, not found in non-aneuploidy phenomenon of variation and polyploidyin the observation process; mitotic index is relatively stable, with an average of16.18%. Population ofStipagrostis pennata and nuclear size changes slightly, different cell population of Stipagrostis pennata and nuclear changes in amplitude,1,2and3sampling different Habitat groups Stipagrostis pennata and4,5,6,7and8sampling different population of cells the size of the group of Stipagrostis pennata showedsignificant differences (p <0.05), the nuclear size and showed increased cell area increases, the average ofcell and karyon size77.72um~2and22.80um~2.(3)Likewise, temperature changes,1,4,8and10, sample different populations of Stipagrostis pennataindoor simulation experiments to analyze changes in cell characteristics under variable temperatureconditions, the study found, three variable temperature conditions, cell and karyon size and mitotic indexshowed a two-high in the middle "peak" shape, indicating that Stipagrostis pennata split a value-addedoptimum temperature30/25°C, above or below the optimum temperature can inhibit cell division;... |
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