the reflectance spectrum of green leaves is considerably affected by their biochemical and biophysical properties. it is possible to extract biochemical information from a continuous vegetation spectrum produced using hyperspectral sensors. the numerous absorption features present in the vegetation spectrum carry a considerable amount of information related to the content and the structure of t...

The leaves of Acer negundo L. var. odessanum (H. Rothe), if permanently exposed to strong sunlight, do not green, but remain yellow and finally become bleached. In yellow leaves the plastids contain single thylakoids and no grana. In plastids of bleached leaves, however, only vesicles are present. The concentration of chlorophylls and photosynthetic activity are much lower in those leaves than ...

Beech leaves were sampled at the end of a prolonged hot dry period at a tree decline site in the Black Forest, Germany to investigate the potential role of flavanols in defense mechanisms against environmental stress. Green and yellowing leaves were harvested from the uppermost canopy of trees that were more than 200 years old and 30 m high. Yellowing leaves had a 7.4-fold higher concentration ...

Why leaves of some trees turn red in autumn has puzzled biologists for decades, as just before leaf fall the pigments causing red coloration are newly synthesized. One idea to explain this apparently untimely investment is that red colour signals the tree's quality to herbivorous insects, particularly aphids. However, it is unclear whether red leaves are indeed less attractive to aphids than gr...

Prunus domestica L. has green leaves, whereas Prunus cerasifera Ehrh. var. atropurpurea has red leaves due to the presence of mesophyll anthocyanins. We compared morphological and photosynthetic characteristics of leaves of these species, which were sampled from shoots grafted in pairs on P. domestica rootstocks, each pair comprising one shoot of each species. Two hypotheses were tested: (1) an...

Previous work (1) has shown that about 50 per cent of the total protein nitrogen contained in a tobacco leaf which had recently completed growth by expansion is associated with particulate structures of leaf protoplasm such as nuclei, chloroplasts, etc. The other 50 per cent of the protein nitrogen remains soluble in the presence of neutral buffers. In the analytical ultracentrifuge, the solubl...

(3Z)-Hexenol, which is commonly called leaf al­ cohol, and (2£)-hexenal, also called leaf aldehyde, are widely distributed in fresh leaves, vegetables and fruits. They are mainly responsible for the socalled “green odour” characteristic of leaves, along with other C6-compounds such as (3£")-, and (2£)-hexenols, their corresponding aldehydes (3Z)-, (3£")-hexenals, «-hexanol and «-hexanal. Thus, ...

The goal of this study was to compare the feeding rates of Balloniscus sellowii on leaves of different decomposition stages according to their phenolic and flavonoid content. Leaves from the visually most abundant plants were offered to isopods collected from the same source site. Schinus terebinthifolius,the plant species consumed at the highest rate, was used to verify feeding rates at differ...

Plants have an ability to prevent chlorophyll accumulation, which would mask the bright flower color, in their petals. In contrast, leaves contain substantial amounts of chlorophyll, as it is essential for photosynthesis. The mechanisms of organ-specific chlorophyll accumulation are unknown. To identify factors that determine the chlorophyll content in petals, we compared the expression of gene...

Introduction: Buckwheat (Fagopyrum esculentum) and wild thyme (Thymus serpyllum) leaves and flowers were used to develop thymo-rutin green tea. The process involved cultivation of buckwheat collection of flowers and leaves after flowering and collection of wild thymus leaves and flowers. Materials and Methods: The leaves and flowers washed and pass through steam to fix color and kept in solar h...