Abstract: In order to study photosynthetic mechanism of the yellow-green leaf mutant——'Jinglingguozi’ of chrysanthemum, the characteristics of photosynthesis and the spectra properties of thylakoid membrane in the green and yellow leaf tissue of the mutant were studied. We measured the photosynthesis, stomatal characteristics, room temperature absorption spectra, chlorophyll emission fluorescence spectra of thylakoid membrane. The results that compared to the green leaf tissue of the mutant, the yellow leaf tissue had lower net photosynthetic rate (P_n), light saturation point (LSP), dark respiration rate (R_d), apparent quantum yield (AQY), but higher light compensation point (LCP). The yellow leaf tissue had lower stomata limit value (L_s), but higher non-stomata limit value. There was no significant difference in the characteristics of stomatal microstructure between the green leaf and yellow leaf tissue. The absorption spectra and fluorescence spectra significantly decreased in the yellow leaf tissue. The yellow leaf tissue had significantly lower capacity of the capture and excitation of light energy and lower the photosynthetic capacity than the green leaf tissue did, which was caused by non-stomata factors, such as a decrease of the function of thylakoid membrane.

Key words: chrysanthemum, leaf color mutant, photosynthetic rate, stomata, thylakoid membrane