Autumn Leaves of Ginkgo biloba L.: Optical Properties, Pigments and Optical Brighteners

Abstract
Senescent leaves of Gingko biloba accumulate fluorescent compounds which may contribute to the golden luminous appearance of the autumnal foliage. Apart from the putative effect of such optical brighteners, the changes of spectral optical properties associated with senescence are due to the breakdown of chlorophyll in conjunction with a remarkably high retention of carotenoids. Carotenoid esters accumulate concomitant with chlorophyll breakdown. Optical properties in the infrared range of the spectrum illustrate the intactness of leaf tissue to the end of the senescence period.