Study On Physiology Characteristic And Landscape Application Of Elsholfizia Argyi

Elsholfizia argyi belongs to Labiatae family, Elsholtzia genera. It is a kind of herb with beautiful flower posture, and unique color of flowers, and it can resistant to heavy mentals.Therefore, it has high potential value of landscape application.The article focused on the study of seed germination characteristics, water stress, shade treatments and landscape applications of Elsholfizia argyi.The conclusion of this research as follows:(1)Seed germination:The result showed that the seed germination rate of Elsholfizia argyi is lower in the natural condition. According to different concentrations of GA3, IAA and NAA soaked for 24 hours compared with those treated with water, as well as sifferent soaking time of anhydrous alcohol and 30 %H₂O₂, the conclusion of promoting effect on seed germination is:IAA 100 mg/L>NAA 200 mg/L>GA3 150 mg/L> H₂O₂ 90 min>anhydrous alcohol 40 min.(2)Water stress:With the water stress increasing, the leaves of Elsholfizia argyi went to hairy,wilting and yellow.While chlorophyll content increased,the leaf relative water content dropped. The physiological indexes including relative conductivity rate,MDA, SOD activity,POD activity and soluble sugar all changed as the increasing of the relative water content of soil, which emboied 20 %>45 %>65 %>80 % >95 %, but soluble protein content dropped. In the later time of stressing, chlorophyll fluorescence parameters such as NPQ, Fm, Fv/Fm, qP, Yield and ETR dropped, but Fo increased. Along with the extension of the water stressing time, leaves of Elsholfizia argyi changed to yellow and dry gradually, even fell off, and the height of plant dropped substantially, and some plants died when the relative water content was higher than 92 %. It was good for Elsholfizia argyi's growthas the relative water content of soil was 65 %～80 %. When the relative water content of soil was during 20 %～65 % ,the growth was limited , while it can't grow well when the realative water content of soil were less 20 % or higher than 92 % .(3)Shade treatments: With the increase of shading extent, the chlorophyll content increased, while the Chla/b decreased;chlorophyll fluorescence parameters such as Fo and NPQ dropped firstly and then rose,but Fm,Fv/Fm,Fv/Fo and qP rose firstly and then dropped. The content of MDA reduced. It can be found that the water content and relative conductivity of leaves increased but when shade was 75 %, they dropped, while the changes were opposite on the contents of soluble sugar and protein.It also can be found that POD activity performed as rose-fell-rose,and its minimum appeared in the shade of 75 %. In conclusion, the most suitable growth light condition of Elsholfizia argyi was in the shade of 75 %. While in the shade of 25 % and 50 %, it can grow normally. Moreover, it can endure the shade of 93 %, but the growth suffocated. And the full sunlight was unsuitable for Elsholfizia argyi.(4)Landscape application: Intergrating the ecological and ornamental characteristics of Elsholfizia argyi, it can be applied to the curb, waterfront, forest edge and woodland environments, etc. to enrich the level and color of plant landscape. It can also be used as functional plants in the copper, zinc and other heavy metals pollution areas to improve the soil environments.