Influence of light’s nature on quality of and photosynthetic pigment contents in flue-cured tobacco
For clarifying the influences of solar spectrum constitution on the quality of and photosynthetic pigment contents in flue-cured tobacco, the appearance quality of and chemical components and photosynthetic pigment contents in flue-cured tobacco growing under different illuminant conditions was investigated by covering different color films. The results showed that: 1) The make-up of visible light in solar spectrum was obviously changed by color film. Red and yellow films tended to reduce the proportion of the light of shorter wavelength, but increase that of longer wavelength. The ratio of all light proportion was reduced by white film. The proportion of longer wavelength light was reduced by blue film. 2) The film covering affected more on color (color gamut, color purity, uniformity, etc.) of cured leaves. 3) The starch content in cured leaves reduced and the ratio of K to Cl increased to a certain extent in all treatments. The total alkaloid content was obviously increased, while the ratio of sugar to nicotine was reduced by red film covering. 4) The ?-carotene content in cured leaves relatively increased in blue film treatment, and the lutein content in cured leaves reduced in all treatments. 5) Total alkaloid significantly negatively correlated with short-wavelength light, while carotenoid significantly positively correlated with short-wavelength light and significantly negatively correlated with long-wavelength light.