to comparison the photosynthetic parameters and leaf chlorophyll content and fluorescence of safflower (carthamus tinctorios l.) cultivars under salinity stress, a pot experiment was carried out as factorial based on completely randomized design with three replications in summer 2011 in university of yasouj. first factor included four salinity levels (zero, 75, 150 and 225 mm (formed as 20 to 1...

The organization of pigment molecules in photosystems is strictly determined. The peripheral antennae have both chlorophyll a and b, but the core antennae consist of only chlorophyll a in green plants. Furthermore, according to the recent model obtained from the crystal structure of light-harvesting chlorophyll a/b-protein complexes II (LHCII), individual chlorophyll-binding sites are occupied ...

Impact of the wheat stem sawßy, Cephus cinctus Norton (Hymenoptera: Cephidae), feeding injury on chlorophyll content and photosystem II (PSII) photochemistry in heads of wheat, TriticumaestivumL., at the grain-Þlling developmental stagewas evaluated by biochemically assessing the total chlorophyll, chlorophyll a (Chla), chlorophyll b (Chlb), chlorophyll a/b ratio (Chla/b), and carotenoid concen...

Abstract Determination of chlorophyll content as an indirect method of estimating the productivity of vegetation represents a good way to gain an understanding of the photosynthetic regime of plants. Physiological investigations of chlorophyll and carotenoid content in the uppermost internode of several wheat cultivars were carried out at the outset of the flowering phase. The dependence of chl...

The spectroscopic (visible) properties of pigment-bearing lipid and protein particles extract­ ed from milk show that: 1) chlorophylls a and b bound to separate particles can form aggregates provided their relative concentration is high enough. Neither pheophytin a nor ^-carotene, in the same conditions, form observable aggregates. 2) Chlorophylls a and b can co-aggregate when they are bound to...

Light-shade adaptation of the chlorophyll a/b containing procaryote Prochlorothrix hollandica was studied in semicontinuous cultures adapted to 8, 80 and 200 mumole quanta per square meter per second. Chlorophyll a contents based on dry weight differed by a factor of 6 and chlorophyll b by a factor of 2.5 between the two extreme light conditions. Light utilization efficiencies determined from p...

Illumination of 3 day old etiolated radish seedlings with continuous white light results in a progressive accumulation of chlorophyll a and b. Both pigments are bound in a different way to the thylakoid chlorophyll-proteins, which appear parallel to the formation of chlorophylls. By applying the SDS-PAGE method to SDS-digested chloroplasts, it was possible to show that the chloroplasts of radis...

Trimeric (bT) and monomeric (bM) light-harvesting complex II (LHCII) with a chlorophyll a/b ratio of 0.03 were reconstituted from the apoprotein overexpressed in Escherichia coli. Chlorophyll/xanthophyll and chlorophyll/protein ratios of bT complexes and 'native' LHCII are rather similar, namely, 0.28 vs 0. 27 and 10.5 +/- 1.5 vs 12, respectively, indicating the replacement of most chlorophyll ...

This work represents an application of the Visible Spectrometry, High Pressure Liquid Cromatography and Electronspray Ionisation-Mass Spectrometry analysis for the identification of chlorophyll and its derivatives, pheophytin and chlorophyllide, in their purified mixtures (the chlorophyll, pheophytin and chlorophyllide fraction, respectively). The chlorophyll, pheophytin and chlorophyllide frac...