The Comparative Research On Three Pilea Under Different Light Stress

To compare the research on three Pilea under different light stress,in the paper,Pilea purpurella,Pilea nummulariifollia and Pilea cadierei Gagnep. were chosen as the experimental materials,then using the artifical climate box to set up 6 low light gradient(5000、2000、1000、500、100、Olux) and two strong light gradient (30000、200001ux),100001ux as control gradient.Under the light stress,to provide a theoretical basis for the landscape application of three Pilea,he plant morphological,leaf water content,relative chlorophyll content and chlorophyll fluorescence of three Pilea were determinated and analysied.The main conclusions are as follows:(1)The optimum intensities of P. purpurella is 1000-100001ux,500-100001ux for P. nummulariifollia and 100-200001ux for P. cadierei Gagnep..The P. Purpurella were the most sensitive to the light enviroment factors,P. nummulariifollia take the second place,P. cadierei Gagnep. is the last one.(2)Under the low light stress,1000-50001ux,500-50001ux and 100-50001ux enhanced the growth performance of the individuals of P. purpurella,P. Nummulariifollia and P. cadierei Gagnep.with dark green leaves respectively.P.purpurella could endure weak light 1001ux 30 days,and endure dark 20days,P. nummulariifollia could endure dark 40 days,and P. cadierei Gagnep. have no plant die in 50 days.Under strong light the height of three Pilea have no significant influence,and the leaf area change scope P. Purpurella> P. nummulariifollia>P. cadierei Gagnep.. Comparative to the control group,the leaf number of P. nummulariifollia have no obvious difference(P<0.05),but the leaf number of P.purpurella and P. cadierei Gagnep. under 200001ux have obvious difference(P> 0.05)(3)Under the two light stress,0-10001ux,01ux intensity could reduced the leaf water content of P. Purpurella and P. nummulariifollia,but the leaf water content of other level had no significant changes.(4)The relative chlorophyll content of P. purpurella,P. nummulariifollia and P. cadierei Gagnep. could reduced by 0-5001ux,0-1001ux,01ux intensities respectively.Under the strong light part,the reduce scope of relative chlorophyll content is P. Purpurella>P. nummulariifollia>P. cadierei Gagnep..(5)Under the low light stress,about F0P. cadierei Gagnep.>P. purpurella>P. nummulariifollia and the F0 of P. cadierei Gagnep.increased by low light stress,the F0 of three P. purpurella>P. nummulariifollia>P. cadierei Gagnep..The Fv/Fm of P. Purpurella and P. nummulariifollia,P. cadierei Gagnep. were reduced by 0-1001ux,01ux respectively,and in the other situations Fv/Fm have no obvious changes,but under the strong light stress,the reduce scope of Fv/Fm is P. purpurella> P. cadierei Gagnep.>P. nummulariifollia.The ETR of P. Purpurella,P. cadierei Gagnep. were increased by 500-50001ux,10000-50001ux intensities respectively.Under the two light stress,the ETR of P. cadierei Gagnep.>P. nummulariifollia.>P. Purpurella.The influence of two light stress to qP,P. cadierei Gagnep.>P. nummulariifollia.>P. Purpurella.