The virescent cotton (Gossypium hirsutum) mutant described here differs from normal cultivated cotton by a single mutation in the nucleus. The mutant exhibits nuclear control of chlorophyll and carotenoid development. Young leaves are distinctly yellow and become green with age. There is no unusual photometabolism of (14)CO(2) or (14)C-acetate in this mutant. It is probable that the nuclear vir...

The chronic ecotoxicological effects of Cd, Cu, Pb, Se and Zn were determined within this study. Mustard seedlings (Sinapis alba L.) were used as a model subject for the tests. The phytotoxicity was determined through the root growth inhibition and photosynthetic pigments production (chlorophyll a, b, total carotenoids). The metal accumulation in the roots and cotyledons was also determined usi...

The relative levels of mRNA for the reaction-centre L and M subunits, B875 (LH1) alpha and beta polypeptides and B800-850 (LH2) alpha and beta polypeptides, have been measured during pigment induction of Rhodobacter sphaeroides. Over the 6 h of the experiment, bacteriochlorophyll levels increased by at least 100-fold. No transcripts for photosynthetic components were detectable at the start of ...

Given that the characteristic of free floating plants to uptake metals can have a positive effect on the efficiency of the remediation process of a wetland, it is important to investigate the factors that may impact the process of uptake of metals by the plants. By conducting this present study over a short duration of time, the effects of salinity on the growth, the content of the photosynthet...

We have previously demonstrated (Armond, P. A., C. J. Arntzen, J.-M. Briantais, and C. Vernotte. 1976. Arch. Biochem. Biophys. 175:54-63; and Davis, D. J., P. A. Armond, E. L. Gross, and C. J. Arntzen. 1976. Arch. Biochem. Biophys. 175:64-70) that pea seedlings which were exposed to intermittent illumination contained incompletely developed chloroplasts. These plastids were photosynthetically c...

The objects of research were the first leaves green seedlings spring barley (Hordeum vulgare L.) varieties Belarusian breeding − filmy (Magutny, Raider) and naked (Adamant). Seedlings different age (3, 5, 10 days old) infected with spores fungus Bipolaris sorokiniana (Sacc.) Shoem. a causative agent helminthosporiasis, analyzed 2 after infection. Varietal ontogenetic differences between cultiva...

The occurrence of antibiotics in surface waters has been reported worldwide with concentrations ranging from ng L-1 to low µg L-1 levels. During environmental risk assessments, effects of antibiotics on algal species are assessed using standard test protocols (e.g., the OECD 201 guideline), where the cell number endpoint is used as a surrogate for growth. However, the use of photosynthetic rela...

Metals have a variety of negative outcomes on plants, essential components of any ecosystem. The effects of CdCl2 (5 μmol L-1), ZnCl2 (25 or 50 μmol L-1), and CuCl2 (2.5 or 5 μmol L-1) and combinations of CdCl2 with either ZnCl2 or CuCl2 on the growth, photosynthetic pigments, and photosystem II (PSII) efficiency of duckweed (Lemna minor L.) were investigated. All of the treatments caused growt...

Solar radiation is the primary energy source for surface planetary life, so that pigments are fundamental components of any surface-dwelling organism. They may therefore have evolved in some form on Mars as they did on Earth. Photosynthetic microbes are major primary producers on Earth, but are concurrently vulnerable to ultraviolet (UV) damage. Using non-intrusive laser Raman spectroscopy to r...