|Statement||[By] J. J. S. van Rensen.|
|Series||Mededelingen Landbouwhogeschool Wageningen. Nederland. 69-14 (1969), Mededelingen (Landbouwhogeschool Wageningen) ;, 69-14.|
|LC Classifications||S239.S2 W3 deel 69-14|
|The Physical Object|
|Number of Pages||11|
|LC Control Number||78549326|
DQ can become reduced to produce a free radical. It can then transfer this electron to molecular oxygen to yield superoxide anion. This redox cycling mechanism allows DQ to generate reactive oxygen species (ROS) resulting in oxidative stress, damage to cellular macromolecules and even cell death. The effect of an increase in salinity on the physiology of the halotolerant chlorophyte Scenedesmus protuberans was studied in light-limited continuous cultures. It was observed that a gradual, as well as a steep increase in salinity resulted in lower by: This study investigated the effects of paraquat, a widely used herbicide, on the aquatic unicellular alga Chlorella vulgaris through short-term toxicity tests at the physiological and gene transcriptional levels. Exposure to μM paraquat increased the activities of the antioxidant enzymes superoxide dismutase, peroxidase, and catalase to levels , , and times higher Cited by: Chlordane is an organochlorine soil insecticide whose effects upon aquatic ecosystems, and particularly on algae, are little known. Experimental results indicate that chlordane concentrations ranging from to μg/ℓ significantly stimulate cell division of Scenedesmus quadricauda, a common planktonic green ane in concentrations from to 50 μg/ℓ is also stimulatory to.
The effects of diquat on gas exchange in illuminated C. vUlgaris have been studied by manometric procedures. Estimates of dark oxygen uptake were made by transfer of treated cells to darkness. Analysis of the results indicates that on adding diquat to C. vUlgariB there is a rapid fall in the rate of apparent photosynthesis. This is due to an immediate and large increase in dark metabolism (C A static microcosm system was used to evaluate effects of the herbicide diquat (–30 mg/L) on the structure and function of naturally derived microbial communities on polyurethane foam substrates. Microbial communities were exposed to a single application of diquat and were monitored for 21 days. Effects on community structure included changes in algal cell density at diquat concentrations. Photosynthesis is a very important metabolic pathway for plant growth and crop yield. This report investigated the effect of the herbicide imazethapyr on photosynthesis in the Arabidopsis thaliana pnsB3 mutant (a defect in the NDH pathway) and pgr5 mutant (a defect in the PGR5 pathway) to determine which cyclic electron transport chain (CET) of the NDH and PGR5 pathways is more . Photosynthesis, the process by which green plants and certain other organisms transform light energy into chemical energy. During photosynthesis in green plants, light energy is captured and used to convert water, carbon dioxide, and minerals into oxygen and energy-rich organic compounds.
The effect of light quality on the products of photosynthesis has been studied in two species of green algae, Chlorella pyrenoidosa and Scenedesmus acuminatus, the blue-green alga Microcystis aeruginosa, and the photosynthetic bacterium Chromatium test organism was placed in C bicarbonate and illuminated at saturation intensities of red, red plus supplementary blue, blue alone, or. The effects of 2,4-D, glyphosate and paraquat on growth, photosynthesis and chlorophyll-a synthesis by a freshwater green alga, Scenedesmus quadricauda Berb , were determined. These herbicides are the most often used in Hong Kong. Two separate mutants of the green alga, Scenedesmus obliquus,are described in which photosynthesis is sensitive to moderate intensities of white light ( mw cm−2). Heterotrophic cultures of both mutants lose photosynthetic activity when exposed to white light; the site of at least the initial phase of this inactivation is within photosystem I. Although all whole cell and cell-free reactions typical of photosystem . The effect of Pb, even at low concentrations (Moreira et al., ), reducing cell growth rates (Irmer, ), and causing structural and functional damage in photosynthesis (Aggarwal et al.,