Chlorophyll degradation enzyme (i.e., chlorophyllase, Mg-dechelatase, and chlorophyll oxidase) activities of aphid-infested and uninfested 'Tugela' and Tugela near-isogenic wheat lines (i.e., Tugela-Dn1, Tugela-Dn2, and Tugela-Dn5) were assayed. Chlorophyllase activity was higher in bird cherry-oat aphid, Rhopalosiphum padi (L.) (Homoptera: Aphididae),-infested wheat lines compared with Russian...

  Salinity is one of the most challenging problems that adversely affects growth and development of plants. Therefore, understanding of the mechanisms that enable plants to adapt to salinity stress will ultimately help in the selection of stress tolerant cultivars for exploiting saline soils. The main objective of this study was to examine the effects of NaCl on some physiological and biochemic...

Degreening, due to the net loss of chlorophyll (Chl), is the most prominent symptom during the processes of leaf senescence, fruit ripening, and seed maturation. Over the last decade or so, extensive identifications of Chl catabolic genes (CCGs) have led to the revelation of the biochemical pathway of Chl degradation. As such, exploration of the regulatory mechanism of the degreening process is...

The pathway of chlorophyll catabolism during leaf senescence is known in a fair amount of biochemical and cell biological detail. In the last few years, genes encoding a number of the catabolic enzymes have been characterized, including the key ring-opening activities, phaeophorbide a oxygenase (PaO) and red chlorophyll catabolite reductase (RCCR). Recently, a gene that modulates disassembly of...

The positive effect of melatonin on the function of the photosynthetic apparatus is known, but little is known about the specific mechanisms of melatonin's action in plants. The influence of melatonin on chlorophyll metabolism of 24-day-old Pisum sativum L. seedlings during paraquat (PQ)-induced oxidative stress was investigated in this study. Seeds were hydro-primed with water (H), 50 and 200 ...

Phytyl diphosphate (PDP) is the prenyl precursor for tocopherol biosynthesis. Based on recent genetic evidence, PDP is supplied to the tocopherol biosynthetic pathway primarily by chlorophyll degradation and sequential phytol phosphorylation. Three enzymes of Arabidopsis (Arabidopsis thaliana) are known to be capable of removing the phytol chain from chlorophyll in vitro: chlorophyllase1 (CLH1)...

Chlorophyll degradation products are preserved in marine sediments over timescales of thousands of years. The production of chlorophyll in the water column is related to biological productivity, so chlorophyll degradation products (chlorins) preserved in marine sediments can be used as indicators of paleoproductivity. A new, rapid, nondestructive method of determining chlorin concentrations in ...

lichens are composite organisms formed by a fungus and a green alga and / or a blue-green bacterium. they are recognized as being very sensitive to atmospheric pollution and respond to factors that influence human and environmental healths. since 1860, lichen has been identified as a biological indicator to detect air pollution in great britain and europe. lichens have the high sensitivityto ni...