The changes in quality ingredients of Qi chrysanthemum flowers treated with elevated UV-B radiation at different growth stages.

The paper mainly reported the changes in quality ingredients of Qi chrysanthemum flowers treated with elevated UV-B radiation at different growth stages. The experiment included two levels of UV-B radiation (ambient UV-B, a 10% increase in ambient UV-B). Elevated UV-B radiation was carried out for 10-days during seedling, vigorous growth, bud and flower stages of Qi chrysanthemum, respectively. Elevated UV-B treatments applied during four development stages did not significantly affect flower yield, the rate of superoxide radical production and malondialdehyde concentration in flowers, while increased free amino acid concentration. The amino acid concentration induced by elevated UV-B radiation applied during bud stage was higher than that during the other stages. Elevated UV-B radiation applied during vigorous growth (except for flavone), bud and flower stages of chrysanthemum significantly increased hydrogen peroxide concentration, phenylalanine ammonia lyase enzyme activity, vitamin C, chlorogenic acid and flavone concentrations in flowers. These results suggested that active and nutritional ingredients in flowers of chrysanthemum could be increased by elevated UV-B radiation applied during the later growth stages of chrysanthemum. The paper supplied a simple and environmental-friendly method to improve quality of medicinal plants.

The effects of UV-B radiation intensity on biochemical parameters and active ingredients in flowers of Qi chrysanthemum and Huai chrysanthemum.

The article studied UV-B effects on biochemical parameters and active ingredients in flowers of Qi chrysanthemum and Huai chrysanthemum during the bud stage. The experiment included four UV-B radiation levels (CK, ambient UV-B; T1, T2 and T3 indicated a 5%, 10% and 15% increase in ambient UV-BBE, respectively) to determine the optimal UV-B radiation intensity in regulating active ingredients level in flowers of two chrysanthemum varieties. Flower dry weight of two cultivars was not affected by UV-B radiation under experimental conditions reported here. UV-B treatments significantly increased the rate of superoxide radical production, hydrogen peroxide (H2O2) (except for T1) and malondialdehyde concentration in flowers of Huai chrysanthemum and H2O2 concentration in flowers of Qi chrysanthemum. T2 and T3 treatments induced a significant increase in phenylalanine ammonia lyase enzyme (PAL) activity, anthocyanins, proline, ascorbic acid, chlorogenic acid and flavone content in flowers of two chrysanthemum varieties, and there were no significant differences in PAL activity, ascorbic acid, flavone and chlorogenic acid content between the two treatments. These results indicated that appropriate UV-B radiation intensity did not result in the decrease in flower yield, and could regulate PAL activity and increase active ingredients content in flowers of two chrysanthemum varieties.

[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. METHOD: 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. RESULT: 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%. CONCLUSION: 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.