[Effects of light intensity on growth and photosynthetic characteristics of Chrysanthemum morifolium].
OBJECTIVE
To investigate the effect of light intensity on growth and photosynthetic of Chrysanthemum morifolium.


METHODS
The growth characteristics of C. morifolium were measured under different treatments (100%, 80%, 60%, 40% and 20% of full sunlight). The photosynthetic characteristics and chlorophyll fluorescence parameters of leaves under different light intensity were determined by a LI-6400 photosynthesis system and a PAM-2100 chlorophyll fluorescence system.


RESULTS
With the reduction of irradiance, the diameter of the stem reduced, plant height, leaf length, leaf width and length/width raised, assimilation product increased; Content of photosynthetic pigment increased between light intensity 100%-40% reduced under 20% treatment, chlorophyll a/b decreased. Light compensation point (LCP), apparent quantum yield (AQY) increased first and reduced later, photosynthesis rate (P(n)), stomatal conductance (G(s)), intercellular CO2 concentration (C(i)) and transpiration rate (T(r)) decreased, stomatal limitation value (L(s)) rose. Chlorophyll fluorescence parameters F(v)/F(m) increased, phiPS II, F(v)'/F(m)', ETR and qP increased between irradiance 100%-60%, NPQ decreased, such as phiPS II decreased and NPQ increased when irradiance was lower than 40%.


CONCLUSIONS
Weak light condition was unfavorable to the growth of C. morifolium and the light conditions of culture should be control between 80%-60% of full sunlight.
Wang
Yanru
Y
Institute of Chinese Medicinal Materials, Nanjing Agricultural University, Nanjing 210095, China.
Guo
Qiaosheng
Q
Jin
Miao
M
D018533:Biomass; D031202:Chrysanthemum / Q000254:growth & development* / Q000502:physiology / Q000528:radiation effects*; D010788:Photosynthesis / Q000528:radiation effects*