Pigment dynamics and autumn leaf senescence in a New England deciduous forest, eastern USA

Abstract

The leaves of woody plants at Harvard Forest in Central Massachusetts, USA, changed color during senescence; 70% (62/89) of the woody species examined anatomically contained anthocyanins during senescence. Anthocyanins were not present in summer green leaves, and appeared primarily in the vacuoles of palisade parenchyma cells. Yellow coloration was a result of the unmasking of xanthophyll pigments in senescing chloroplasts. In nine red-senescing species, anthocyanins were not detectable in mature leaves, and were synthesized de novo in senescence, with less than 20 m g cm -2 of chlorophyll remaining. Xanthophyll concentrations declined in relation to chlorophyll to the same extent in both yellow-and red-leaved taxa. Declines in the maximum photosystem II quantum yield of leaves collected prior to dawn were only slightly less in the red-senescing species, indicating no long-term protective activity. Red-leaved species had significantly greater mass/area and lower chlorophyll a / b ratios during senescence. Nitrogen tissue concentrations in mature and senescent leaves negatively correlated to anthocyanin concentrations in senescent leaves, weak evidence for more efficient nitrogen resorption in anthocyanic species. Shading retarded both chlorophyll loss and anthocyanin production in Cornus alternifolia , Acer rubrum , Acer saccharum , Quercus rubra and Viburnum alnifolium . It promoted chlorophyll loss in yellow-senescing Fagus grandifolia . A reduced red : far-red ratio did not affect this process. Anthocyanins did not increase leaf temperatures in Q. rubra and Vaccinium corymbosum on cold and sunny days. The timing of leaf-fall was remarkably constant from year to year, and the order of senescence of individual species was consistent.

Genetic analysis for anthocyanin and chlorophyll contents in rapeseed

“…The results indicated that both studied traits were significantly affected by the environment. This might be due to the environmental factors such as UV-A, UV-B, temperature, light intensity, nutrition and moisture regulated the synthesis of anthocyanin in leaves (LEE et al, 2003;SCHABERG et al, 2003;TOSSI et al, 2011;WANG et al, 2012). In addition, highly significant difference between generations on the traits were detected, especially between parental lines (Figure 1).…”

Reviews and syntheses: Australian vegetation phenology: new insights from satellite remote sensing and digital repeat photography

“…4). This increase in redness may be due to the build-up of anthocyanin pigments that cause the red colouration of senescing leaves, also a distinct feature of deciduous forest canopies in autumn (Hoch et al, 2001;Lee et al, 2003;Gould, 2004). This species, W. laevis, may be found further north in semi-deciduous and deciduous vegetation communities that are connected floristically to the rainforests of the Daintree region.…”

A Cellular Timetable of Autumn Senescence

“…Carotenoids are not the only pigments responsible for autumn colors; anthocyanins often accumulate (Lee et al, 2003), giving rise to dark-reddish leaf colors, and have been proposed to function as light protectants during the nutrient recycling of senescing leaves (Feild et al, 2001;Hoch et al, 2003). Therefore, we quantified anthocyanin levels to see whether they changed during autumn senescence in aspen leaves.…”

“…Every autumn deciduous trees need to shed their leaves and prepare for the winter. Autumnal senescence is spectacular in many trees, when leaves change color from green to yellow and/or red (Lee et al, 2003). The different colors arise from the preferential degradation of chlorophylls over carotenoids and the synthesis of red-colored pigments like anthocyanins (Goodwin, 1958;Lichtenthaler, 1987).…”