Effect of gibberellic acid on marigold (Calendula Officinalis L.) was evaluated in a pot culture experiment. A factorial experiment based on completely randomized design including 12 treatments and four replications was carried out. Main factor was foliar application stages (first, second and third) and sub factor included different concentrations of GA3 (0, 50, 150 and 250 mg L...

Carotenoids are a family of natural fat-soluble nutrients important for antioxidant defense (Packer, 1992, 1993; Cadenas and Packer, 2002) found throughout the plant kingdom. They are responsible for the red, orange or yellow color of many fruits and vegetables, such as pineapples, citrus fruits, peaches, nectarines, persimmons, tomatoes, papaya, apricots, carrots, watermelons, pumpkins, squash...

The detection of hydrogen peroxide, chlorophyll pigments, anthocynin, carotenoids, total phenolic compounds and lipid peroxidation levels as potential stress signaling molecules in tomato (Lycopersicon esculentum Mill.) leaves in response to specific mineral deficiency were studied. The stress signaling molecules were measured in the plant leaves at different growth time points cultured in spec...

Chlorophyll degradation is an aspect of leaf senescence, which is an active process to salvage nutrients from old tissues. non-yellow coloring1 (nyc1) is a rice (Oryza sativa) stay-green mutant in which chlorophyll degradation during senescence is impaired. Pigment analysis revealed that degradation of not only chlorophylls but also light-harvesting complex II (LHCII)-bound carotenoids was repr...

Chlorophyll fluorescence and hyperspectral reflectance were used to evaluate physiological responses to two common stressors in coastal environments. Chlorophyll content is one indicator of drought and salinity vegetation stress because of its direct role in the photosynthetic process and electron transport. Recent advances in fluorescence spectroscopy have led to the development of numerous re...

The oxygen consumption of a starved chlorophyll-free, yellow mutant of Chlorella vulgaris is enhanced by very small amounts of blue light (lambda 450 mmu); a saturation level is reached at about 500 ergs cm(-2) sec(-1). At that intensity the respiration is about 3 times greater than in the dark. An action spectrum for the enhancement of respiration shows 2 peaks around lambda 450 and 375 mmu. F...

The net photosynthetic rate (NP), chlorophyll fluorescence, carotenoid content and chlorophyll content of the cosmopolitan moss Bryum argenteum were measured in the field at Botany Bay, southern Victoria Land, continental Antarctica (778S). Comparisons were made between sunand shade-adapted forms, and changes were followed as the moss emerged from under the snow and during exposure of shade and...

Light-induced pigment destruction was studied in ripening apple (Malus domestica Borkh., cv. Antonovka) fruits with reflectance spectroscopy. The reflectance spectral changes attributable to light-induced transformation of xanthophyll cycle carotenoids (Car) preceded the pigment degradation. In green fruits, the destruction of chlorophyll and Car proceeded synchronously up to complete disappear...

Color changes often accompany the onset of ripening, leading to brightly colored fruits that serve as attractants to seed-dispersing organisms. In many fruits, including tomato (Solanum lycopersicum) and pepper (Capsicum annuum), there is a sharp decrease in chlorophyll content and a concomitant increase in the synthesis of carotenoids as a result of the conversion of chloroplasts into chromopl...