Treatment of maize seedlings with different concentrations of sorbitol decreased the rate of germination substantially. Root and shoot length was also reduced by sorbitol treatment, however, decrease in root length was lower than shoot length. Incubation of leaf segments from maize seedlings grown in continuous light with sorbitol decreased the fresh weight and increased the dry weight in a con...

High-frequency, high-field EPR at 330 GHz was used to study the photo-oxidized primary donor of photosystem I (P(700)(+)(*)) in wild-type and mutant forms of photosystem I in the green alga Chlamydomonas reinhardtii. The main focus was the substitution of the axial ligand of the chlorophyll a and chlorophyll a' molecules that form the P(700) heterodimer. Specifically, we examined PsaA-H676Q, in...

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...

Action spectra of the Emerson effect in Chlorella and Navicula reveal peaks at 670 mut, in addition to those at 650 mu (Chlorella) and 630 mmicro (Navicula) attributable to chlorophylls b and c. Thus, excitation of chlorophyll a form "chlorophyll a 670" can supplement, in these algae, the excitation of the form "chlorophyll a 680-700." The effect of the auxiliary pigments in these algae may be ...

The synthesis of chlorophyll and ribulose diphosphate carboxylase as well as the development of Hill reaction activity were followed in expanding Populus deltoides leaves and related to photosynthetic patterns. Total chlorophyll, which was not correlated with photosynthetic rate in expanding leaves, decreased slightly with age in very young leaves, due to a decrease in chlorophyll b, but then i...

cadmium is a highly toxic heavy metal and one of the most important environmental pollutants. cadmium has a particular interest among the heavy elements due to the high mobility, solubility, and toxicity for human, plants, and other organisms. in order to study cadmium toxic effect on green pepper, a completely randomized design was performed with three levels of cadmium (0, 0.25, and 0.5 mm as...

Maillard Reaction Products (MRP) was prepared from glucose and glysine heated at 90 ̊C in air circulating oven for 12 hours. The effect of MRP on chlorophyll stability in green peas was investigated. The addition of Maillard Reaction Products (MRP) decreased the loss of chlorophyll a, chlorophyll b and total chlorophyll. The conversion of pheophytin and pyropheophytin was also reduced by the add...

UV-B radiation induced alterations in the contents of photosynthetic pigments, antioxidants (phenolics and ascorbic acid) and chlorophyll fluorescence in two tropical variants of Trichosanthes cucumerina L. – Cucurbitaceae. The Green (Variant A) and Light Green (Variant B) variants of T. cucumerina, which had earlier been shown to differ in their total phenolics contents, were used for the stud...