Response of leaf phenotypes and photosynthetic characteristics of golden-leaf Ginkgo biloba to shading
[Objective]To investigate the light demand of golden-leaf Ginkgo,and to provide reference basis for its artificial cultivation technology management.[Method]5-year-old golden-leaf Ginkgo was used as the test material,differentiated into golden-leaf strain and green-leaf strain,and the leaf phenotypes,cell structure,photosynthetic pigments,photosynthetic parameters,and chlorophyll fluorescence parameters were determined in different shade,so as to compare and analyze the effects of shade on golden-leaf Ginkgo.[Result]The leaf length,leaf width,leaf area,total leaf thickness,palisade tissue thickness,and spongy tissue thickness gradually increased with the increasing shade intensity in the golden-leaf strain,and total leaf thickness,upper and lower epidermal thickness,palisade tissue thickness,and spongy tissue thickness showed a tendency of increasing and then decreasing with shade intensity in the green-leaf strain.The L*and b* values of the leaves of the golden-leaf strain decreased gradually with the increase of shading intensity,and the a* value showed a tendency of decreasing and then increasing;the L*,a* and b* values of the leaves of the green-leaf strain all decreased gradually with the increase of shading intensity.The chlorophyll a,chlorophyll b,total chlorophyll and carotenoid contents of the leaves of the green-leaf strain were significantly higher than those of the golden-leaf strain under all shading treatments,and the pigment contents of the leaves of the two strains firstly increased and then decreased with the increase of the shading intensity;the net photosynthetic rate,the transpiration rate,and the stomatal conductance of the golden-leaf and green-leaf strains all decreased gradually with the increase of the shading intensity,and the molar fractions of the inter-cellular CO2 showed the tendency to increase firstly and then decrease.Initial fluorescence(Fo),maximum fluorescence(Fm),variable fluorescence(Fv),potential photochemical activity of PSⅡ(Fv/Fo),and maximum photochemical efficiency of PSⅡ(Fv/Fm)of the leaves of the golden-leaf strain increased gradually with increasing shade intensity,and the changes in Fv/Fo and Fv/Fm of the leaves of the green-leaf strain were consistent with those of the golden-leaf strain.Based on the results of the principal component analysis,the green-leaf strain ranked 1st in the composite score at 30% shading treatment,and the golden-leaf strain ranked 3rd in the composite score at 50% shading treatment.[Conclusion]The 50% shading condition is suitable for the growth of golden-leaf ginkgo strain,and the 30% shading condition is suitable for the growth of green-leaf ginkgo strain.
万方数据
维普
