Bleaching Herbicides, Algae, Scenedesmus acutus, Carotenoids, Chlorophyll, Air/Nitrogen Gassing Over 24 and 48 hour cultivation periods the influence of SAN 9789 (norflurazon), EMD-IT 5914 (difunon) and fluridone on growth, photosynthetic oxygen evolution and pigment content of the green alga Scenedesmus acutus was determined. Four effects were observed: a) Both carotenoid and chlorophyll forma...

Half a century of research into the physiology and biochemistry of sun-shade acclimation in diverse plants has provided reality checks for contemporary understanding of thylakoid membrane dynamics. This paper reviews recent insights into photosynthetic efficiency and photoprotection from studies of two xanthophyll cycles in old shade leaves from the inner canopy of the tropical trees Inga sapin...

Photosynthetic microalgae have a high potential for the production of biofuels and highly valued metabolites. However, their current industrial exploitation is limited by a productivity in photobioreactors that is low compared to potential productivity. The high cell density and pigment content of the surface layers of photosynthetic microalgae result in absorption of excess photons and energy ...

In evergreen conifers, where the foliage amount changes little with season, accurate detection of the underlying "photosynthetic phenology" from satellite remote sensing has been difficult, presenting challenges for global models of ecosystem carbon uptake. Here, we report a close correspondence between seasonally changing foliar pigment levels, expressed as chlorophyll/carotenoid ratios, and e...

The performance of three different rootstock (Adara (Prunus cerasifera L.), SL 64 (Prunus mahaleb), and Colt (Prunus avium x Prunus pseudocerasus)) as nutrient suppliers has been studied for sweet cherry cultivars (Prunus avium L.). The results obtained suggested that, depending on the rootstock, the trees are submitted to different degrees of stress. According to the data obtained, it could be...

Comparison of the growth parameters and photosynthetic capacities of cells of Aphanocapsa 6714 under various growth conditions led to the following conclusions: (a), no enzymic regulation of CO(2)/glucose assimilation takes place in this strain; (b), functioning of photodependent phosphorylating pathways turns off oxidative ATP synthesis; (c), no efficient regulation of pigment synthesis exists...

Allelopathic effects of plant residues is an important research avenue regarding optimization of rotation systems in agronomy. The aim of this study was to investigate the allelopathic effects of four plant residues, namely, black cumin, dragonhead, dill, and soybean on the germination and growth of wheat (Triticum aestivum) in different cropping systems. Results showed that applicatio...

Eleven proteins belonging to photosystem II (PSII) bind photosynthetic pigments in the form of thylakoid membrane-associated pigment-protein complexes. Five of them (PsbA, PsbB, PsbC, PsbD and PsbS) are assigned to PSII core complex while the remaining six (Lhcb1, Lhcb2, Lhcb3, Lhcb4, Lhcb5 and Lhcb6) constitute, along with their pigments, functional complexes situated more distantly with regar...

Chlorosomes are the main light harvesting complexes of green photosynthetic bacteria. Recently, a lamellar model was proposed for the arrangement of pigment aggregates in Chlorobium tepidum chlorosomes, which contain bacteriochlorophyll (BChl) c as the main pigment. Here we demonstrate that the lamellar organization is also found in chlorosomes from two brown-colored species (Chl. phaeovibrioid...