The living organisms are known to be often exposed to oxidative stress due to the action of most of environmental factors: the exposure to athmospheric oxygen (O2), the pollution, the ozone and the ultraviolet radiation level increasing. The consequence of this fact is the biomolecules (proteins, nucleic acids and lipids) damaging. The oxidative stress mainly affects the membranous systems of a...

The effects of irrigation water salinity on growth, chlorophyll contents, proline and nutrients accumulation and K/Na ratio in three walnut cultivars was investigated. Three irrigation water salinity levels with electrical conductivities of 1,5, 3, and 5.0 dS/m and tap water as a control treatment were used in a randomized design with four replications. Irrigation practices were realized by con...

Isoelectrofocusing has been used to separate various chlorophyll-protein complexes of pho­ tosystem two (PS II). Light-harvesting complexes containing chlorophyll a and chlorophyll b (LHC II) were located in bands having p/s in the region of 4.5. At slightly higher pH other light-harvesting complexes containing little or no chlorophyll b were found. In the most basic region of the isoelectrofoc...

A stroma fraction that has photosystem 1 activity and grana lamellae fractions that have activities for both photosystems were isolated by differential centrifugation of a needle valve homogenate. Subsequent fractions, corresponding to photosystems 1 (F-1D) and 2 (F-2D) were isolated by digitonin treatment of the grana lamellae (P-10K) and compared with respect to their chlorophyll composition ...

in order to investigate the effects of corm tunic, corm weight and drought stress on saffron (crocus sativus l.), an experiment was conducted at the greenhouse of ferdowsi university of mashhad, iran. treatment were combination of four corm weights range (2-4, 4-6, 6-8 and 8-10 g), two levels of water availability (100% field capacity and drought) and two levels of corm tunic (natural corm with...

boron toxicity is becoming more extensively widespread in arid and semi arid regions, due to the application of either saline waters or irrigation waters containing a relatively high b content. results of research indicate that addition of certain plant nutrients such as n may reduce the harmful effect of high b levels. therefore, the present experiment was undertaken to evaluate the interactiv...

increasing energy demands associated with economic growth and industrialization have resulted in dramatic increases in air pollution emissions. air pollution damages the plant mainly by disrupting cell homeostatic conditions.in the present study, diverse plant criteria indicating air pollution from different levels including cell biochemistry, leaf and tree crown in the plane-tree were determin...

The effects of different concentrations (0, 25, 50, 75 and 100%) of aqueous leachate of Achillea biebersteinii on germination characteristics, seedling growth, photosynthetic pigments and protein contents of pepper (Capsicum annuum L.) were investigated through conducting laboratory and greenhouse experiments. Leachate of A. biebersteinii affected negatively germination percentage, germination ...

Cytochrome b(6)f complexes contain a molecule of chlorophyll a (Chla), which, in Chlamydomonas reinhardtii, can be exchanged for extraneous chlorophyll during protracted incubation of the purified complex in detergent solution. The specificity of the site and its location in the complex have been studied by photochemical coupling and circular dichroism spectroscopy. Following substitution of th...