Two triticale cultivars ZC 237 (Al-resistant) and ZC 1890 (Al-sensitive) were used to investigate the effects of 30 to 100 µM Al on antioxidative enzyme activity, lipid peroxidation and cell wall composition. In ZC 1890, the root elongation was significantly inhibited after 1-h exposure to 50 µM Al, the changes in hemicellulose fraction were clearly detected after 2-h Al exposure, while the peroxidase (POD) and superoxide dismutase (SOD) activities significantly increased after 6-h exposure, and the malondialdehyde (MDA) content after 12-h exposure. The similar patterns were also found in ZC 237. Treatment of ZC 1890 with 1 mM citrate for 30 min after 3-h exposure to Al resulted in significant decrease of Al bound to cell-wall and recovery of root elongation. These results suggested that Al affected cell wall before the damage of plasma membrane, but this was not the primary cause of root elongation inhibition.

Ailanthus altissima, a fast-growing and contamination-resistant species is investigated for its use in areas contaminated by heavy metals. A micropropagation protocol for A. altissima was developed, cultured shoots were tested for in vitro heavy metals tolerance. Proliferation rate and shoot length were affected by 6-benzylaminopurine (BAP) and Murashige and Skoog's (MS) salt concentrations, best results were obtained in full strength MS medium supplemented with 1.32 or 2.64 µM BAP. Rooting percentage was strongly influenced by indole-3-butyric acid. Cultures of A. altissima exposed to heavy metals demonstrated a tolerance comparable to species already utilized in phytoremediation.

A high frequency in vitro shoot bud differentiation and multiple shoot production protocol from hypocotyl segments of 8 to 10-d-old seedlings of cotton has been developed. Murashige and Skoog (MS) basal medium with Nitsch and Nitsch vitamins was found to be optimal in shoot regeneration. A combination of 2 mg dm^-3 thidiazuron and 0.05 mg dm^-3 naphthaleneacetic acid was the most effective for shoot regeneration (76 %) and an average of 10.6 shoots per responding explant. Combination of the cytokinins benzylaminopurine and kinetin induced better regeneration response than their individual treatments. Supplementation of the culture medium with ethylene inhibitor silver nitrate and activated charcoal showed beneficial effects. Optimal rooting was obtained on half-strength MS medium supplemented with 1 mg dm^-3 indolebutyric acid and activated charcoal. Scanning electron micrographs of in vitro cultured explants revealed that shoot primordia were formed de novo.

The culture of Saussurea medusa cell were cultured in an internal loop airlift bioreactor with sifter draft tube (ILABSDT) was investigated. Under the optimal culture conditions, which were inoculation size 1.5 g(d.m.) dm^-3, aeration rate 0.3 dm³(air) dm^-3(medium) min^-1, and 14 mesh sifter holes, the maximum biomass, syringin content and syringin production reached 11.7 g(d.m.) dm^-3, 17.7 mg g^-1 and 206.6 mg dm^-3, respectively. Among cell cultures in shake flask, bubble column bioreactor and ILABSDT, ILABSDT had the highest syringin productivity and reached 12.41 mg dm^-3 d^-1.

Lemna minor L. treated with 20, 50, or 100 µM CuSO₄ accumulated Cu and reactive oxygen species (hydrogen peroxide and superoxide radical) in frond and root cells. The time-course analysis of lipid peroxidation showed high increment in malondialdehyde production only after 12 and 48 h of Cu treatment. Guaiacol peroxidase and superoxide dismutase activities decreased after 48 h while glutathione reductase activity enhanced 48 h after Cu-treatment. Ascorbate and glutathione contents increased with the increasing Cu stress.

The asynchronous programmed cell death (PCD) in different regions of the cotton cotyledon was studied during senescence. We showed that changes in chlorophyll contents do not occur at the same time in different parts of the cotyledon. By using light microscopy (LM) and the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end in situ labelling (TUNEL) methods, the symptoms of cell death were detected in cotyledon margins earlier than in the central part. DNA ladders were detected by gel electrophoresis in senescent cotyledon margins and in the centre respectively, but not in the whole cotyledons.

In the present study, in vitro regeneration system for a recalcitrant woody tree legume, Leucaena leucocephala (cvs. K-8, K-29, K-68 and K-850) from mature tree derived nodal explants as well as seedling derived cotyledonary node explants was developed. Best shoot initiation and elongation was found on full-strength Murashige and Skoog (MS) medium supplemented with 3 % (m/v) sucrose, 100 mg dm^-3 myoinositol, 100 mg dm^-3 glutamine, 20.9 µM N ⁶-benzylamino-purine (BAP) and 5.37 µM 1-naphthalene acetic acid (NAA). Rooting was induced in half-strength MS medium containing 2 % (m/v) sucrose, 100 mg dm^-3 myoinositol, 14.76 µM indole-3-butyric acid (IBA) and 0.23 µM kinetin. The cultivar K-29 gave the best response under in vitro conditions. Rooted plantlets were subjected to hardening and successfully transferred to greenhouse. Further, somatic embryogenesis from nodal explants of cv. K-29 via an intermittent callus phase was also established. Pronounced callusing was observed on full-strength MS medium containing 3 % (m/v) sucrose, 100 mg dm^-3 myoinositol, 40.28 µM NAA and 12.24 µM BAP. These calli were transferred to induction medium and maximum number of globular shaped somatic embryos was achieved in full-strength MS medium fortified with 3 % (m/v) sucrose, 100 mg dm^-3 myoinositol, 15.0 µM 2,4-dichlorophenoxyacetic acid (2,4-D), 5.0 µM BAP and 1.0 mM proline. Moreover, an increase in endogenous proline content up to 28^th day of culture in induction medium was observed. These globular shaped somatic embryos matured in full-strength MS medium with 3 % (m/v) sucrose, 100 mg dm^-3 myoinositol, 10.0 µM BAP, 2.5 to 5.0 µM IBA and 0.5 mM spermidine.

This paper describes the effect of NaCl on the respiration of Citrus cell suspensions namely on the induction of the alternative oxidase. The exposure of two Citrus (cvs. Carvalhal tangor and Valencia late) cell suspensions to 200 or 400 mM NaCl lead to a reduction on cell respiration rates. Under these conditions, the respiration rate decreased less in the presence of KCN indicating a stimulation of the capacity of the alternative oxidase (AOX). In addition, immunoblots showed an increase on the amount of AOX protein. Antibodies raised against the Sauromatum guttatum enzyme recognized the reduced form of the enzyme near the 35 kDa band. The protein accumulation was correlated with the significantly higher AOX capacity observed for cv. Carvalhal tangor.

Seed protein diversity of fourteen lentil cultivars grown in Turkey was studied by using sodium dodecyl sulfate polyacrylamide gel electrophoresis. A distance matrix was produced based on five polymorphic protein bands, scored for their absence as 0 and presence as 1. Seed protein distances among the cultivars ranged from 0.00 to 0.80. The dendrogram based on the distance matrix indicated two distinct clusters. The first cluster includes the cultivars Sultan 1, Meyveci 2001 and Kayi 91. The second cluster contains the cultivars Pul 11, Ozbek, Emre 20, Malazgirt 89, Ciftci, Seyran 96, AliDayi, Firat 87, Sazak, Erzurum 89 and YerliKirmizi.

We describe the optimized storage conditions of recombinant Potato virus A coat protein (ACP) carrying two different epitopes from Human papillomavirus type 16 (HPV-16). Epitope derived from minor capsid protein L2 was expressed as N-terminal fusion with ACP while an epitope derived from E7 oncoprotein was fused to its C-termini. The construct was cloned into Potato X potexvirus (PVX) based vector and transiently expressed in plants using Agrobacterium tumefaciens mediated inoculation. The effect of storage conditions on the serological activity of L2ACPE7 was studied by ELISA using IgG anti PVX, PVA and L2. Purified L2ACPE7 stored freeze-dried (at -20 °C), frozen at various temperatures (-20 °C, -70 °C) and at +4 °C were tested. Purified L2ACPE7 was most stable as lyophilized material stored at -20 °C. Our study demonstrates suitable way for the storage of plant material containing foreign viral epitopes for the purposes of edible vaccination.

Fucosylation in plants occurs in glycoproteins and polysaccharides but the function of fucosylation is largely unknown. We aimed to analyze the effects of over-expression of human fucosyltransferase III (hFucT III) on in vivo N-glycan accumulation in tobacco plant leaves and focused on comparing the amount of Lewis a (Le^a)-epitope accumulation in transgenic and in wild-type plants. Fucosyltransferase assays, Western blot and mass spectrometry were used to identify, quantify and analyse Le^a N-glycans. We found that constitutive overexpression of hFucT III activity had no effect on Le^a complex type N-glycans accumulation. Our results suggest that tobacco recombinant hFucT III acts more as a hydrolase than as a transferase.

Shoot buds were induced directly on either side of midrib from adaxial surface of immature leaf explants in Stevia rebaudiana Bertoni five weeks after culturing in Murashige and Skoog's nutrient medium supplemented with 8.88 µM of N ⁶-benzylaminopurine and kinetin ranging from 4.65 to 6.98 µM. Immature leaves of 0.6 to 1 cm were found to produce best response (93 %) with a highest number of 4.93 shoot buds per explant. For elongation of regenerated shoot buds, MS medium supplemented with 30 g dm^-3 sucrose and indole-3-butyric acid (IBA) ranging from 4.92 to 7.38 µM were found most suitable. The medium was further modified to suit bioreactor cultivation of regenerated shoots wherein the use of two-fold MS salts and 60 g dm^-3 sucrose resulted in a high biomass yield of 50.68 g dm^-3 (m/v) accounting for about 590 micro-cuttings in three weeks. Best rooting of micro-cuttings occurred in half strength MS medium supplemented with IBA ranging from 4.92 to 7.38 µM, 15 g dm^-3 sucrose and gelled with 0.8 % agar. Rooted plants were successfully established in substrate containing sand, Vermicompost and garden soil in equal proportions and grown in greenhouse. This is the first report on direct shoot regeneration from Stevia leaves.

Two selection systems for Agrobacterium tumefaciens mediated transformation of tomato and potato were compared. In the tomato (Lycopersicon esculentum cv. Moneymaker), the highest transformation rate, 4.2 %, of cotyledon explants on mannose-selection medium was obtained when mannose/sucrose concentration in the regeneration medium was 5/15 g dm^-3. The best transformation efficacy with the commonly used concentration of 100 mg dm^-3 kanamycin as a selection agent was 9 %. In the potato (Solanum tuberosum cv. Bintje), the highest transformation frequency was 53.3 % when mannose concentration in the regeneration medium was 5 g dm^-3 during the first 3 weeks after transformation and 10 g dm^-3 afterwards. The optimum concentration of sucrose was 20 g dm^-3. The transformation efficiency using kanamycin as a selection agent at a concentration 100 mg dm^-3 was 33.3 % with potato. Our results demonstrate that the transformation efficiency using mannose selection is 1.6-fold higher for potato and about 2 times lower for tomato comparing with the ordinary protocol using kanamycin.

Thirty five bands (alleles) from six enzyme systems and fifty seven random amplified polymorphic DNA (RAPD) fragments were selected to analyse the genetic diversity of 33 polyploid wheatgrasses (Triticeae) populations of species Thinopyrum junceiforme and Elytrigia pycnantha, and two hybrids, one pentaploid and one novel 9-ploid. Dice's similarity coefficient, the UPGMA-derived phenograms from RAPD, and allozymes markers showed that the clustering of wheatgrass populations was based on ploidy level. These markers had similar levels of diversity between populations, with high genetic similarity within the same ploidy-level and within population's individuals. The tetraploid Th. junceiforme populations are closely related, with a large similarity distances varied from 0.8 to 1. Based on the isozyme and RAPD analyses, diploid taxa are related to polyploids with similarity coefficients 0.4.

Inflorescence explants of two winter wheat cultivars, Triticum durum cv. Kiziltan-91 and T. aestivum cv. Bezostaja-01, were used to evaluate the effects of vernalization period of donor plants, callus age and medium composition on regeneration capacity. Donor plants were grown for 7 d and they were exposed to 4 °C for 1, 2, 3, 4, and 5 weeks. The maximum inflorescence formation was observed as 79 % at 4 weeks and 73 % at 5 weeks of vernalization period for Kiziltan-91 and Bezostaja-01, respectively. Among 6 different callus induction and regeneration mediums, I₁-R₁ and I₃-R₃ have to be the best responding mediums for Kiziltan-91 and Bezostaja-01, respectively. In Kiziltan-91, calli induced from donor plants, vernalized for 3 weeks, showed a significantly lower regeneration capacity than counterparts vernalized for 4 and 5 weeks. The highest regeneration capacity of 69 % was obtained from 6-week-old calli produced from 4 weeks vernalized Kiziltan-91 donor plants. In contrast to Kiziltan-91 cultures, the effects of vernalization period and callus age on regeneration capacity were not significant in Bezostaja-01 cultures. The maximum numbers of tillers were obtained from 6-and 15-week-old calli for Bezostaja-01 and Kiziltan-91, respectively. In contrast to vernalization period of donor plants, callus age had no effect on seed number.

Apple (Malus × domestica Borkh. cv. Golden Delicious) trees were inoculated with fungal pathogens, corresponding either to an incompatible strain of Venturia inaequalis or to non-host pathogens (Venturia pyrina, Alternaria brassicicola) in order to characterize the regulation of PR-10 genes in these different situations in relationship to symptom development. Macro-and microscopic observations of the plant-fungus interactions revealed typical symptoms of resistance with V. inaequalis and symptoms of hypersensitivity (HR) on around 5 % of leaves with V. pyrina. No HR was microscopically observed with A. brassicicola. In the non-host situations, the PR-10 expression in leaves at the transcriptional level was not (A. brassicicola) or very slightly (V. pyrina) activated. This strongly suggests that PR-10 is not a component of the non-host resistance in the interactions studied here. By contrast specific up-regulation of PR-10 was evident after inoculation with V. inaequalis.

Effects of exogenous salicylic acid (SA) on plant growth, contents of Na, K, Ca and Mg, activities of superoxide dismutase (SOD), guaiacol peroxidase (GPX), ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), glutathione reductase (GR) and catalase (CAT), and contents of ascorbate and glutathione were investigated in tomato (Lycopersicon esculentum L.) plants treated with 100 mM NaCl. NaCl treatment significantly increased H₂O₂ content and lipid peroxidation indicated by accumulation of thiobarbituric acid reactive substances (TBARS). A foliar spray of 1 mM SA significantly decreased lipid peroxidation caused by NaCl and improved the plant growth. This alleviation of NaCl toxicity by SA was related to decreases in Na contents, increases in K and Mg contents in shoots and roots, and increases in the activities of SOD, CAT, GPX and DHAR and the contents of ascorbate and glutathione.

The accumulation of steviol glycosides (SGs) in cells of Stevia rebaudiana Bertoni both in vivo and in vitro was related to the extent of the development of the membrane system of chloroplasts and the content of photosynthetic pigments. Chloroplasts of the in vitro plants, unlike those of the intact plants, had poorly developed membrane system. The callus cells grown in the light contained proplastids of almost round shape and their thylakoid system was represented by short thylakoids sometimes forming a little number of grana consisting of 2-3 thylakoids. In cells of the etiolated in vitro regenerants and the callus culture grown in the dark, only proplastids practically lacking the membrane system were observed. All the chloroplasts having developed thylakoids and forming at least a little number of grana were equipped with photochemically active reaction centers of photosystems 1 and 2. Leaves of in vivo plants accumulated greater amount of the pigments than leaves of the in vitro plants. In both the callus culture grown in the light and the etiolated in vitro regenerants, the content of the pigments was one order of magnitude lower than that in leaves of the intact plants. The callus tissue grown in the dark contained merely trace amounts of the pigments. Leaves of the intact and the in vitro plants did not exhibit any significant differences in photosynthetic O₂ evolution rate. However, photosynthetic O₂ evolution rate in the callus cells was much lower than that in the differentiated plant cells. The in vitro cell cultures containing merely proplastids did not practically produce SGs. However, after transferring these cultures in the light, both the formation of chloroplasts and the production of SGs in them were detected.

An efficient in vitro propagation of kava (Piper methysticum) was established. Utilizing 15-d-old tender shoots from dormant auxiliary buds as explants, significant induction of vigorous aseptic cluster shoots was achieved in Murashige and Skoog (MS) medium containing 0.5 mg dm^-3 6-benzyladenine (BA), 0.5 mg dm^-3 indole-3-acetic acid (IAA), and antibiotics after 30 d. In vitro rooting was achieved at 100 % efficiency in MS medium containing 0.75 to 1.00 mg dm^-3 IAA or indole-3-butyric acid and 3 % sucrose. The most robust and long roots were observed in medium with IBA. Moreover, the embryonic callus was induced from petioles in MS medium supplemented with 1.0 mg dm^-3 BA and 0.1 mg dm^-3 IAA, of which 70 % differentiated into shoots in the presence of 1.0 mg dm^-3 BA and 0.5 mg dm^-3 IAA.

The effects of Al, Cd and pH on growth, photosynthesis, malondialdehyde (MDA) content, and some antioxidant enzyme activities of the two soybean cultivars with different Al tolerance were determined using a hydroponic culture. There were six treatments as follows: pH 6.5; pH 4.0; pH 6.5 + 1.0 µM Cd; pH 4.0 + 1.0 µM Cd; pH 4.0 + 150 µM Al; pH 4.0 + 1.0 µM Cd + 150 µM Al. The results showed that the low pH (4.0) and Al treatments caused marked reduction in the growth (root and shoot length and dry mass), chlorophyll content (SPAD value) and net photosynthetic rate. Higher malondialdehyde content, superoxide dismutase (SOD) and peroxidase (POD) activities were detected in the plants exposed to both Al and Cd than in those exposed to Al treatment alone. An expressive enhancement of SOD and POD was observed in the plants exposed to 150 µM Al in the comparison with the control plants, especially in Al-sensitive cv. Zhechun 2 which had also significantly higher Al and Cd content than Al tolerant cv. Liao-1. Cd addition increased Al content in the plants exposed to Al + Cd stress, and cv. Zhechun 2 had relatively lower Al content. The present research indicated that Al and Cd are synergistic in their effects on plant growth and some physiological traits.

The DNA genetic diversity of 40 accessions of genus Leymus was analyzed by random amplified polymorphic DNA (RAPD) markers. A total of 352 products were amplified by 34 10-mer arbitrary primers, among which 337 products (95.74 %) were found to be polymorphic. 5-14 polymorphic bands were amplified by each polymorphic primer, with an average of 9.91 bands. The data of 352 RAPD bands were used to generate Jaccard's similarity coefficients and to construct a dendrogram by means of UPGMA. Great genetic diversity in genus Leymus was observed, the genetic diversity among the different species more abundant than that of the different accessions, and the different accessions in a species or the species from the same areas were clustered together.

Multiple shoots of Spilanthes acmella Murr. were induced from nodal buds of in vivo and in vitro seedlings on Murashige and Skoog (MS) medium containing 1.0 mg dm^-3 6-benzyladenine (BA) and 0.1 mg dm^-3 α-naphthalene-acetic acid (NAA). Adventitious shoots were successfully regenerated from the leaf explants derived from the above mentioned multiple shoots. The efficiency of shoot regeneration was tested in the MS medium containing BA, kinetin, or 2-isopentenyl adenine in combination with NAA, indole-3-acetic acid (IAA), or indole-3-butyric acid (IBA) and gibberellic acid. Maximum number of shoots per explant (20 ± 0.47) was recorded with 3.0 mg dm^-3 BA and 1.0 mg dm^-3 IAA. An anatomical study confirmed shoot regeneration via direct organogenesis. About 95 % of the in vitro shoots developed roots after transfer to half strength MS medium containing 1.0 mg dm^-3 IBA. 95 % of the plantlets were successfully acclimatized and established in soil. The transplanted plantlets showed normal flowering without any morphological variation.

Ex vitro transfer is often stressful for in vitro grown plantlets. Water stress and photoinhibition, often accompanying the acclimatization of in vitro grown plantlets to ex vitro conditions, are probably the main factors promoting production of reactive oxygen species (ROS) and in consequence oxidative stress. The extent of the damaging effects of ROS depends on the effectiveness of the antioxidative systems which include low molecular mass antioxidants (ascorbate, glutathione, tocopherols, carotenoids, phenols) and antioxidative enzymes (superoxide dismutase, ascorbate peroxidase, catalase, glutathione reductase, monodehydroascorbate reductase, dehydroascorbate reductase). This review is focused on ROS production and development of antioxidative system during in vitro growth and their further changes during ex vitro transfer.

Rapid shoot multiplication of Nyctanthes arbor-tristis L. was achieved from axillary meristems on Murashige and Skoog (MS) basal medium supplemented with 1.0-1.5 mg dm^-3 6-benzylaminopurine (BA), 50 mg dm^-3 adenine sulfate (Ads) and 3 % (m/v) sucrose. Inclusion of indole-3-acetic acid (IAA) in the culture medium along with BA + Ads promoted a higher rate of shoot multiplication. Maximum mean number of microshoots per explant (6.65) was achieved on the MS medium supplemented with 1.5 mg dm^-3 BA, 50 mg dm^-3 Ads and 0.1 mg dm^-3 IAA after 4 weeks of culture. The elongated shoots rooted within 13 to 14 d on half-strength MS medium supplemented with either indole-3-butyric acid (IBA), IAA or 1-naphthaleneacetic acid (NAA) with 2 % sucrose. Maximum percentage of rooting was obtained on medium having 0.25 mg dm^-3 IBA and 0.1 mg dm^-3 IAA. About 70 % of the rooted plantlets survived in the greenhouse. The in vitro raised plants were grown normally in the field.

The present work is focused on the possible relationship between nitric oxide and the induction of proline in response to salt stress. The plants were subjected to 100 mM NaCl and sodium nitroprusside (SNP; the donor of NO) at different concentrations. The plants showed lower NaCl-induced oxidative stress and proline accumulation after application of low concentrations of SNP together with the NaCl treatment. The reduction in the proline content was related to increased activity of proline dehydrogenase. These results suggest that the NO could be capable of mitigating damage associated with salt stress.

The observed inability of 6-d-old seedlings of spring wheat (Triticum aestivum L.) to tolerate the same water deficit as compared to the 4-d-old seedlings seems to be associated with the higher carboxypeptidase and lower aminopeptidase activities. Free amino acid pools differentiated also the 4-d-old seedlings from the older ones. Dehydration decreased the amino acid content in 4-d-old seedlings, increased it in 6-d-old seedlings and changed composition of amino acid pool. In tolerant phase of wheat seedling growth carboxypeptidase activity increased in response to water deficit and aminopeptidase activity increased in dehydrated seedlings, independently of their age.

We investigated some aspects of flooding tolerance in two riparian populations (exposed and no exposed to flooding) of Luehea divaricata C. Martius. Plants derived from seeds collected in each population were submitted to flooding (30 and 60 d), submergence and re-aeration treatments. Plants exposed to flooding showed development of aerenchyma, hypertrophic lenticels and new adventitious roots. Interestingly, whereas the plants originated from population naturally exposed to flooding developed some of these alterations more markedly, they could not survive when totally submerged. The random amplified polymorphic DNA (RAPD) markers, showed a significant difference between populations, suggesting that seasonal flooding on riparian populations of L. divaricata has been selecting individuals who are more adapted to survive in these conditions.

Non-transformed and transformed embryogenic cultures of alfalfa (Medicago sativa L. cv. Zaječarska 83), long-term maintained on growth regulator-free medium, were histologically analyzed. In all examined cultures, somatic embryos at various stages of development were observed and secondary embryos were formed in the cotyledonary, hypocotylary and radicular region of the primary embryos. Detailed histological analysis of the torpedo shape somatic embryo revealed that secondary somatic embryos arose directly from single epidermal cells of hypocotylary axis after an unequal periclinal division. Bipolar proembryos were composed of one smaller cytoplasm rich cell and one larger more vacuolated cell. Further cell division pattern was similar for both non-transformed and transformed embryos. However, multicellular origin of secondary embryos in a direct process and even from callus can not be excluded.