Study On Chlorophyll Fluorescence Character Of Chief Plants In Kubqi Sandy Land

The experiment was conducted to measure chlorophyll fluorescence parameters which were measured by portable chlorophyll fluorescence analyzer (PAM-2100 Walz Germany) among Caragana korshinskii, Salix cheilophila, Hedysarum leave, Artemisia ordosica, Lespedeza davurica and Medicago sativa in Kubqi sandy land. The chlorophyll fluorescence parameters included initial fluorescence(F0), maximum fluorescence(Fm), potential activity(Fv/F0), primary transformation efficiency of light quantity in PSII(Fv/Fm), quotiety of cancellation photochemistry(qP), quotiety of no cancellation photochemisty(NPQ), qusntum yield of photochemistry(Y)and electron transmition rate(ETR). When the environment was changed from illumination to dark, leaf of green plants needed some time for stablizition. The experiment was conducted to define the dark adaption time. The results showed that the dark adaption time of Medicago sativa, Hedysarum leave and Lespedeza davurica demanded simply five minutes When it was 10min, Astragalus adsurgens and Artemisia ordosic displayed the best state. the first option of Salix cheilophila was thirty minute.Chlorophyll fluorescence parameters were compared among Caragana korshinskii, Salix cheilophila, Hedysarum leave, Artemisia ordosica, Lespedeza davurica and Medicago sativa. The value of Fm,Fv/F0,Fv/Fm,qP,Y of Caragana korshinskii, Salix cheilophila, Hedysarum leave and Artemisia ordosica were significantly higher than Lespedeza davurica and Medicago sativa. However, the value of NPQ of Medicago sativa and Lespedeza davurica were higher.In clam and cloudless weather, diurnal changes on chlorophyll fluorescence parameters were measured from 6:00 to 18:00. With the gradual increase of light intensity and leaf temperature, chlorophyll fluorescence parameters, such as Fm, Fv/F0, Fv/Fm, qP and Y showed minimum at noon. Gragh of ETR about Caragana korshinskii, Salix cheilophila, Hedysarum leave, Artemisia ordosica performanced unimodal type. Whereas, The line about ETR of Medicago sativa and Lespedeza davurica were bimodal curve.