Seed storage proteins of Ebenus cretica were fractionated to albumins, globulins, prolamins and glutelins according to their solubility in water, 0.5 M NaCl solution, 55 % propanol-2 and 0.125 M sodium borate (pH 9.0) containing 0.5 % SDS (sodium dodecyl sulfate) solution, respectively. Glutelins consist of the major (about 81 %) fraction of the total extracted proteins. Analysis by SDS-PAGE revealed that the total extracted protein patterns from different racemes of the same plant were similar, while those from seeds of different plants were different. In addition, distinct differences were observed within protein patterns of alkaline extractable glutelin fractions and salt soluble globulin fractions. In E. cretica four ecotypes (A - D) were distinguished by SDS-PAGE of total extracted seed proteins. The last method was more simple and rapid than others and was suggested for screening analysis.

Effect of free radical scavengers and metal chelators on polyethylene glycol (PEG, osmotic potential -1.5 MPa) induced oxidative damage in detached rice leaves was investigated. PEG treatment resulted in a decrease in relative water content and an increase in proline content, and lipid peroxidation. PEG treatment also decreased chlorophyll and protein contents. Free radical scavengers (ascorbate, sodium benzoate, reduced glutathione, and thiourea) retarded and metal chelators [2,2'-bipyridine (BP), 8-hydroxyquinoline, and 1,10-phenanthroline] prevented PEG-induced oxidative damage. Furthermore, the protective effect of BP was reversed by adding Fe²⁺ and Cu²⁺, but not by Mn²⁺ or Zn²⁺. The protective effect of BP is most likely mediated through chelation of iron. It seems that oxidative damage induced by PEG may require the participation of iron.

The relationship between nutrient composition, crop biomass, and glutamate dehydrogenase (GDH) isoenzyme pattern was investigated in soybean (Glycine max) and maize (Zea mays) by monitoring the nutrient induced isomerization of the enzyme from the seedling stage to the mature crop. GDH was extracted from the leaves of the plants, and the isoenzymes were fractionated by isoelectric focusing followed by native polyacrylamide gel electrophoresis. The isomerization V_max values for soybean GDH, similar to maize GDH increased curvilinearly from 200 - 400 μmol mg^-1 min^-1 as the inorganic phosphate nutrient applied to the soil decreased from 50 - 0 mM. In soybean, combinations of N and K, P, or S nutrients induced the acidic and neutral isoenzymes, and gave biomass increases 25 - 50 % higher than the control plant. GDH isoenzymes were suppressed in soybean that received nutrients without N, K, or P and accordingly the biomass was about 30 % lower than the control. Treatment of maize with NPK nutrients increased the GDH V_max values from 138.9 at the vegetative to 256.4 μmol mg^-1 min^-1 at the reproductive phase, and suppressed the basic isoenzymes, but induced both the acidic and neutral isoenzymes thereby inducing seed production (27.0 ± 1.4 g per plant); whereas both the acidic and basic isoenzymes were suppressed in the control maize, and seeds did not develop. Simultaneous induction of the acidic, neutral, and basic isoenzymes of GDH indicated the occurrence of senescence. Therefore in maize and soybean, the induction of the acidic and basic isoenzymes of GDH led to the enhancement of biomass.

The effect of organic (Fe-EDTA and Fe-EDDHA) and inorganic (FeCl₃) iron substances on rooting of the rootstock GF-677 (Prunus amygdalus × Prunus persica) in vitro was studied. Full rooting (100 %) was observed in explants nourished with Fe-EDDHA, while less rooting was found in the absence of iron or in the presence of FeCl₃. On the contrary, no root formation was observed in explants nourished with Fe-EDTA, which showed extremely lower chlorophyll and high iron contents at the end of the experiment.

Auxins were analysed in roots, stems with apical shoots, and leaves of beans (Phaseolus vulgaris L. cv. Zorin) cultured for three weeks on media supplied with different concentrations of jasmonic acid (JA). Morphology changes induced by applied JA were reflected in tissue-specific changes of auxins.

Rooting of Eucalyptus globulus shoots was influenced by the concentration of the indole butyric acid (IBA) and NH₄ ⁺ in the root-induction medium. Optimum plantlet vigor and survival were achieved using low concentrations (1 - 2.5 μM) of IBA and when NH₄NO₃ was removed. Removal of NH₄ ⁺ also had a significant effect on medium pH, its presence caused a decrease in pH as the culture period proceeded. When different nitrate compounds (excluding NH₄NO₃) were used as the nitrogen source, the medium pH was more stable and this was associated with higher root production. The higher root production, in association with appropriate IBA concentrations, produced plantlets with higher survival and better growth on transfer to soil.

The objective of the study was to investigate the effect of As on some physiological parameters of maize in the early growth phases. Seedlings grown in a climatic box in a Hoagland-Arnon nutrient solution were treated with 0, 2 and 5 mg(As) dm^-3 (pH 5.5). After 5 d of As treatment the changes in growth, leaf gas-exchange, chlorophyll (Chl) content, Chl fluorescence, peroxidase activity and lipid peroxidation in roots were recorded. The applied As decreased the growth, leaf area, and biomass accumulation, induced lipid peroxidation and increased peroxidase activity, especially at concentration 5 mg(As) dm^-3. It also decreased the Chl, carotenoid (Car) and protein contents. A decrease in the variable to maximum fluorescence ratio (F_v/F_m) indicated lower photosynthetic efficiency.

Identification of gene expression patterns in mangroves grown under salinity will help to reveal the molecular mechanisms of salt tolerance. Here, 10 cDNAs of genes were isolated from Kandelia candel and identified by representational difference analysis of cDNA (cDNA RDA) under different NaCl concentrations. Of five genes expressed preferentially under salt condition, two were unknown, three were two kinds of low molecular mass heat-shock proteins (sHSPs) and ADP-ribosylation factor, respectively. The expressions of other five genes were repressed under NaCl stress, two encoded cyclophilins, three were tonoplast intrinsic protein, early light-induced protein and 60S ribosomal protein, respectively.

High-frequency regeneration of shoots was achieved at root region of seedlings of Robinia pseudoacacia L. cultured from seeds on medium supplemented with thidiazuron (TDZ, 1.0 μM). The roots of intact seedlings proliferated and formed a compact callus followed by differentiation of numerous shoots. Corresponding cultures on benzylaminopurine-containing medium exhibited much weaker response. Hypocotyl segments also formed shoots at a lower concentration of TDZ (0.1 μM). The shoots formed on TDZ-containing medium were well-developed and readily rooted on hormone-free medium. The obtained plants after acclimation in culture room survived after transfer to soil.

The effect of Pseudomonas fluorescens treatment and Fusarium oxysporum f. sp. cubense inoculation on induction of phenylalanine ammonia-lyase (PAL), peroxidase (POX), chitinase, β-1,3-glucanase and accumulation of phenolics in banana (Musa sp.) was studied. When banana roots were treated with P. fluorescens strain Pf10, a two-fold increase in phenolic content in leaf tissues was recorded 3 - 6 d after treatment. Challenge inoculation with F. oxysporum, the wilt pathogen, steeply increased the phenolic content in P. fluorescens-treated banana plants. Significant increase in POX activity was detected 6 - 9 d after P. fluorescens treatment. PAL, chitinase and β-1,3-glucanase activities increased significantly from 3 d after P. fluorescens treatment and reached the maximum 6 d after treatment. Challenge inoculation with F. oxysporum further increased the enzyme activities. These results suggest that the enhanced activities of defense enzymes and elevated content of phenolics may contribute to bioprotection of banana plants against F. oxysporum.

The seeds of two barley (Hordeum vulgare L.) cultivars (a drought resistant cv. Tokak-137/57 and a drought sensitive cv. Erginel-90) were imbibed either in distilled water (control) or in a solution containing 40 mg dm^-3 paclobutrazol (PBZ) and air dried. Seeds were germinated and grown in a glasshouse for 21 d and seedlings were subjected to salt stress by treating them with 100 and 200 mM NaCl for 12 d. The height of shoots was significantly decreased and root length was increased in PBZ-treated plants prior and after NaCl stress for 12 d leading to an increase in root to shoot ratio. Leaf chlorophyll and carotenoid contents in PBZ treated plants were increased in controls and especially in plants subjected to salt stress. PBZ induced increase in superoxide dismutase (SOD) activities was higher in cv. Tokak-157/37, than in cv. Erginel-90. However, an increase in SOD activity was not accompanied by an increase in peroxidase activity.

Trigonelline (TRG) is a conjugate of nicotinic acid, and is postulated to function as a compatible solute in response to salinity- and water deficit-stresses. TRG concentrations and several agronomic characteristics were measured under irrigated field and non-irrigated field conditions within 18 soybean (Glycine max) genotypes using leaves taken from different growth stages (vegetative, flowering and pod development). Under irrigation, relative water content (RWC) ranged from 90.0 to 99.6 %. Under non-irrigation, RWC ranged from 86.3 to 97.5 %. TRG concentration ranged from 364 to 555 μg g^-1(d.m.) under irrigation, and from 404 to 570 μg g^-1(d.m.) under non-irrigation. TRG concentrations increased in the majority of genotypes (15 of 18) under non-irrigation even though RWC did not significantly differ in many genotypes between treatments. TRG decreased as plants progressed to pod development and seed filling. Mean seed yield under non-irrigated conditions declined 55 % relative to the irrigated controls. TRG concentrations among all genotypes were significantly correlated with seed yield.

Almost all processes in the life of a plant are directly or indirectly affected by both stresses and phytohormones. Nevertheless, apart from abscisic acid, the role of phytohormones in plant response to water stress is far from being fully elucidated. This review tries to answer the question whether interactions between abscisic acid and some other phytohormones might be important in the regulation of stomatal opening during water stress and subsequent rehydration. Firstly, it describes the changes in the contents of individual endogenous phytohormones during water stress. Then, it deals with the effects of applied phytohormones on stomatal opening, and on transpiration and photosynthetic rates in different plants species. Finally, it focuses on the alleviation or stimulation of absicic acid-induced stomatal closure by application of other phytohormones.

Efficiency of pretreatment as foliar spray of indole-3-acetic acid, gibberellic acid and kinetin, each ranging from 0.1 to 10.0 μM concentration, in restoring the metabolic alterations imposed by NaCl salinity was investigated in Vigna radiata (L.) Wilczek. Glycolate oxidase, superoxide dismutase, catalase and peroxidase activities increased under stress in leaves and roots also. Malondialdehyde content and total peroxide content also increased under stress. All the three hormones used were able to overcome to variable extents the adverse effects of stress imposed by NaCl to these parameters.

The nodal and internodal explants excised from the orthotropic shoots of Sesbania sesban var. bicolor elicited the development of shoots directly from the explants as well as via an intervening callus phase on Nitsch (N) medium. On benzyladenine (BA) supplemented media, the adventitious shoot buds developed involving a callus phase. An average of 8.9 ± 4.1 shoots developed per nodal explant on N medium containing 0.5 mg dm^-3 BA in 95 % cultures, whereas 65 % cultures of internodal explants developed shoots with an average of 5.9 ± 3.6 shoots per explant on N medium supplemented with 1.0 mg dm^-3 BA. On kinetin (Kn) supplemented medium shoots developed directly from the surface of both the explants at all the concentrations tried. Nodal explants on N medium supplemented with 1.5 mg dm^-3 Kn developed an average of 12.5 ± 7.9 shoots per explant in 100 % cultures, while internodal explants induced an average of 11.6 ± 7.4 shoots per explant in 75 % explants at 0.5 mg dm^-3 Kn. The in vitro regenerated shoots developed roots when implanted on N medium supplemented with 2 mg dm^-3 indole-3-butyric acid (IBA), after 30 d of inoculation. The in vitro developed plantlets were initially acclimatized under controlled conditions for four months, prior to their transfer to the field.

For most crops growing in polluted areas or treated with agricultural chemicals, no genotoxicity assays are available. We have studied the possibility of using the alkaline protocol of the plant-based molecular assay - the Single Cell Gel Electrophoresis (SCGE) assay (also called Comet assay) as a method for detecting induced DNA damage in 8 agronomic important plants (ordered according to the diameter of the nuclei): sugar beet, alfalfa, tobacco, lentil, maize, potato, hard wheat, and bread wheat. The monofunctional alkylating agent ethyl methanesulphonate (EMS) was applied as a model genotoxic agent on young excised leaves of the tested crops for 18 h at 26 °C in the dark. With increasing concentrations of 2 to 10 mM EMS, the DNA damage, expressed by the averaged median tail moment values, significantly increased in nuclei of all crops studied. No correlation between the diameter of nuclei and sensitivity to EMS treatment was observed. The data obtained demonstrate the feasibility of using the Comet assay for detecting induced DNA damage in crops.

Tissue-specific distribution of basic β-1,3-glucanase (Glu2), basic class II chitinase (Ch2), basic class IV chitinase (Ch4), and acidic class III chitinase (SE2) were examined both in leaves and roots of sugar beet treated with salicylic acid (SA), benzothiadiazole (BTH) and glycine betaine. Protein localization was monitored by immunohistological analysis using specific antibodies. BTH, SA as well as glycine betaine induced both Glu2 and chitinase isozymes in leaves and roots of treated plants. The enzymes were accumulated in extracellular space and cell walls. They were mostly deposited in parenchyma cells of leaves and cortex parenchyma and endodermis of roots. In leaf tissues, BTH and SA induced proteins more effectively than glycine betaine but the effect of glycine betaine in roots was as efficient as BTH and SA. Glycine betaine induced the formation of extracellular globuli containing Ch4. Induced proteins were spatially distributed over the whole plant regardless the site of the inducer application.

Explants of four F₁ hybrids (OMR 36-41/1, OMR 36-41/2, OMR 36-41/4 and OMR 36-41/5) and two cultivars (Rayong 1 and Rayong 60) of cassava (Manihot esculenta Crantz) were subjected to different combinations of 2,4-dichlorophenoxyacetic acid (2,4-D), 1-naphthaleneacetic acid (NAA), kinetin (KIN) and N⁶-benzylaminopurine (BAP) to induce somatic embryogenesis, organogenesis and micropropagation. Shoot apices of the F₁ hybrids exhibited higher frequency (62 - 74 %) of proliferation of somatic embryos than the cultivars (21 - 43 %) in Murashige and Skoog basal medium supplemented with 8 mg dm^-3 2,4-D and 0.5 mg dm^-3 NAA. Nodal explants of regenerated plantlets were rapidly micropropagated with 90 % efficiency on a medium containing 0.1 mg dm^-3 NAA and 0.05 mg dm^-3 BAP irrespective of explant source.

More than 500 isolates of bacteria were obtained from the aerial part and rhizosphere of sweet pepper (Capsicum annuum L.) plants harvested from different places in the Region of Murcia (Spain). The isolates were purified and assayed in vitro against Phytophthora capsici and Alternaria alternata. Sixty isolates (12 %) produced an inhibition zone against at least one of the pathogens, while ten had a strongly inhibitory effect on both pathogens assayed. Microscopic observation of interactions zone showed cell vacuolisation, hyphae lysis and spilling of cytoplasm content of the pathogens in the culture media. These ten isolates were then chosen for biocontrol of Phytophthora root rot and Alternaria leaf spots of pepper plants in vivo. Four of them denominated HS93, LS234, LS523 and LS674 reduced P. capsici root rot by 80, 51, 49 and 54 %, respectively, and A. alternata leaf spots by 54, 74, 62 and 53 %. HS93 belongs to the genus Bacillus and probably the species subtilis, while LS234, LS523 and LS674 belong to the genus Bacillus and probably the species licheniformis. Dry mass of plants treated with these bacteria was significantly higher than that of non-treated and inoculated plants.

Amaranthus hypochondriacus plants were grown under three photosynthetic photon flux densities (PPFD). Mature plants grown at full sunlight (38.8 mol m^-2 d^-1) had higher maximum net photosynthetic rate (P_N) and significantly higher leaf trypsin inhibitor activity than plants that developed under lower PPFD (19.4 and 12.8 mol m^-2 d^-1). In contrast, seeds collected from plants fully exposed to sunlight showed the lowest activity of trypsin inhibitor, higher rate of germination and susceptibility to infection by Aspergillus niger.

Salt tolerant callus and cell suspension cultures of Brassica oleracea L. var. botrytis were obtained by the selection of cells from cultures growing in medium supplemented with 85, 170, and 255 mM NaCl. Salt adapted calli and cell suspensions differed in their RNA and protein concentrations. These concentrations tend to diminish in calli and increase in cell suspensions, both at one or three weeks periods of growth in NaCl. Contents of sucrose and reducing sugars, however, accumulate similarly both in calli and cell suspensions after NaCl treatments. The activity of sucrose synthase was higher in salt adapted cells than in controls. Calli exposed to 255 mM NaCl for six months synthesized a 27 kDa polypeptide, while a 13 kDa polypeptide present in control conditions was absent under salinity. Several high molecular mass polypeptides (> 200 kDa) were visualized in control calli and at moderate salt concentrations, when conditions of the gel were modified.

Wild type of Arabidopsis thaliana plants were cultivated hydroponically in Hoagland and Arnon nutrient solution and treated with copper (5 - 100 µM) for 2, 4, 7 and 14 d. A progressive decrease of the root length and biomass was observed at increasing Cu concentration in the nutrient solution. Roots accumulated higher amounts of Cu than shoots at all Cu treatments. Changes of cell and chloroplast ultrastructure of Cu-treated plants were also observed. Cu application did not induce formation of Cu-phytochelatin complexes. Changes in glutathione and glutathione disulfide content observed in roots and shoots of Cu-treated plants suggest their participation in amelioration of metal-induced oxidative stress.

Difference in the growth response to submergence between coleoptiles and roots of rice (Oryza sativa L.) was investigated in 9-d-old rice seedlings. The coleoptile length in the submergence condition was much greater than that in aerobic condition, whereas the root length in the submergence condition was less than that in the aerobic condition. Alcohol dehydrogenase (ADH) activity in the coleoptiles in the submergence condition was much greater than that in the aerobic condition, but ADH activity in the roots in the submergence condition increased slightly. These results suggest that the preferential ADH induction in rice seedlings may contribute to the difference in the growth response between the coleoptiles and roots under low oxygen conditions.