Levels of non-protein thiols (mostly glutathione, GSH), ascorbic acid (AA), and activities of the enzymes ascorbate peroxidase (AP), glutathione reductase (GR) and GSH S-transferase (GST) were determined in cell-free leaf extracts of acifluorfen-resistant and -sensitive tobacco plants. These parameters were examined also in detached leaves of the above plants exposed to acifluorfen stress. In l...

BACKGROUND Bemisia tabaci MEAM1 (Middle East-Asia Minor 1) feeding alters antioxidative enzyme activity in some plant species. Infestation of B. tabaci nymphs decreases Myzus persicae performance on systemic, but not local leaves of tobacco plants. However, it is unclear if B. tabaci nymphs induced antioxidant activities contributing to the aphid resistance. METHODOLOGY/PRINCIPAL FINDINGS We ...

Shifts in spectral distribution of light were determined within and below a canopy of field-grown burley tobacco (Nicotiana tabacum L. cv. Burley 21). The leaves transmitted much far red light relative to red and blue light. Thus, shaded leaves received more far red light, relative to red and blue, than was received by unshaded leaves. Under field conditions, tobacco plants within rows grew tal...

Enzyme activities of tobacco leaves were compared in detergent extracts. Highest levels of chlorogenic acid oxidase, malate-NAD oxidoreductase, and acid phosphatase were obtained from bud tissues. Peroxidase activity was least in young leaves and highest in senescent leaves yellowed with Ethrel. Peroxidase zymograms obtained by means of disc electrophoresis showed differences in isozyme composi...

Tobacco is a salt-sensitive glycophyte crop species. In this work effect of silicone (Si) supplementation (1 mM as Na2SiO3) was studied in Nicotiana rustica L. cv. Basmas grown hydroponically in growth chamber under control, low (25 mM) and high (75 mM) NaCl concentration for two weeks. Dry matter production of leaves was depressed by salinity level as low as 25 mM and higher salt concentration...

Thymosin β4 (Tβ4) is a peptide that is known to play important roles in protection, regeneration, and remodeling of injured tissues in humans, and that shows great promise in a range of clinical applications. However, current strategies to Tβ4 are insufficient to meet growing demand and have a number of limitations. In this current study we investigated whether expression of recombinant Tβ4 in ...

It has been pointed out that tobacco accumulates cadmium as well as other potentially toxic heavy metals. A three year study was carried out to provide information on the concentration of heavy metals in air-cured (Burley), flue-cured (Virginia) and sun-cured (Oriental-filling) tobacco produced in the Thessaly region of central Greece. During the years 1998, 1999 and 2000, 474 composite surface...

Only two species of tobacco, Nicotiana tabacum L. and N. rustica L., have found an important place in cultivation for chewing or smoking purposes. N, rustica is now of little importance in agriculture, having been supplanted by AT', tabacum except in parts of Poland, Union of Soviet Socialist Republics, Asia Minor, and India. In both of these species the fundamental arrangement of the leaves al...

The aim of the present work was to determine the in¯uence of different B dosages on foliar biomass and quality in tobacco plants (Nicotiana tabacum L var Tennesse 86). Tobacco plants were grown under controlled conditions and submitted to regular fertilisation with macro-and micro-nutrients. The B was applied to the nutrient solution in the form of H 3 BO 3 at 5 mM (B1), 10 mM (B2) and 20 mM (B...

Laminarin, a linear beta-1,3 glucan (mean degree of polymerization of 33) was extracted and purified from the brown alga Laminaria digitata. Its elicitor activity on tobacco (Nicotiana tabacum) was compared to that of oligogalacturonides with a mean degree of polymerization of 10. The two oligosaccharides were perceived by suspension-cultured cells as distinct chemical stimuli but triggered a s...