Hairy roots of Plumbago indica were established at high frequency (90 %) by infecting leaf explants with Agrobacterium rhizogenes strain ATCC 15834. The axenic root cultures were established under darkness in hormone-free liquid Murashige and Skoog medium containing 3 % sucrose. The highest plumbagin content was found to accumulate in roots at their exponential phase of growth. A low pH (4.6) and a low concentration of sucrose (1 %) were beneficial for root growth in darkness, while pH 5.6 and 3 % sucrose under continuous irradiance enhanced plumbagin accumulation in roots up to 7.8 mg g^-1(d.m.). Direct shoot regeneration from hairy root culture was also achieved under continuous irradiance, thus indicated an easy way of obtaining transformed P. indica plants.

Gas exchange in paclobutrazol-treated triticale plants during water stress and rehydration was studied. Seed treatments with the retardant (1 and 25 mg dm^-3) alleviate negative effect of PEG-induced water stress. Net photosynthetic rate, transpiration rate, stomatal conductance, relative water content, and leaf water potential were higher while peroxidase activity and free proline concentration were lower in the paclobutrazol-treated plants than in control plants. This confirmed our assumption that paclobutrazol possessed a protective effect against water stress.

Seed germination and micropropagation protocols of the medicinal species Maytenus canariensis (Loes.) G. Kunkel & Sunding were optimized. In vitro seed germination occurred (86 to 94.7 %) only after treatment of the seeds with H₂SO₄, followed by surface sterilization and culture on solid nutrient medium without any growth regulators. Micropropagation failed when explants were taken from mature trees, and browning of the nutrient medium frequently occurred despite testing many growth media. Nonetheless, adventitious shoot regeneration was achieved employing axillary or apical buds taken from 2-2.5 months old plantlets obtained after in vitro germination of seeds, following culture on nutrient media supplemented with benzylaminopurine, kinetin and naphthalenacetic acid (NAA), attaining up to 3.9 shoots per explant, after 4-6 months. Root induction was best on a medium containing 4.0 mg dm^-3 NAA, achieving a 100 % induction. After hardening of rooted plants, survival after transfer to soil was 71.43 %.

A near isogenic line (NIL) of Brassica oleracea var. botrytis with resistant and susceptible lines C712 and C731, was used in this study. More than 100 differentially expressed cDNA fragments were obtained from black rot resistant cauliflower plants obtained using cDNA-amplified fragment length polymorphism (AFLP) after infection with the pathogen. Thirteen of these fragments were cloned and subjected to reverse Northern blot analysis using both infected and control cDNA pools. Two positive clones, M2 and M6, were isolated. Northern dot blot and Northern blot analyses showed that M2 was constitutively expressed, whereas M6 contained a gene that was differentially expressed during pathogen infection. Moreover, M6 cDNA fragment was also highly expressed 16-24 h after H₂O₂ treatment. Southern blots showed that M6 is a single copy gene in the cauliflower genome, and encodes a protein with 84 % homology to gene on Arabidopsis chromosome 1. The deduced M6 protein has 91 % positive homology with the Arabidopsis 2A6 protein, which regulates ethylene synthesis; 76 % homology with a 1-aminocyclopropane-1-carboxylate oxidase (ACO), the last enzyme in ethylene synthesis; and 70 % homology with an ethylene induced DNA binding factor. These results suggest that M6 gene fragment is a new H₂O₂ downstream defense related gene fragment and can be induced by Xanthomonas campestris pv. campestris and H₂O₂.

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.

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.

Effects of high night temperature on the lipid and protein compositions in the tonoplasts isolated from the leaves of two Crassulacean acid metabolism (CAM) plants, Ananas comosus (pineapple) and Kalanchoë pinnata were studied. The results showed that the phospholipids/protein ratios in the tonoplasts isolated from pineapple and K. pinnata leaves decreased from 1.82 to 1.21 and 2.63 to 1.50, respectively, as the night temperature increased from 20 to 37 °C. Under high night temperature, relative amount of total unsaturated fatty acids in K. pinnata was increased by 6 %, which was mainly caused by increased C18:2 and C18:3, whereas unsaturated fatty acids, C18:2 and C18:3 in pineapple did not show significant change. The distribution patterns of tonoplast proteins in the two CAM species were different between normal and high night temperature and in K. pinnata, especially those with molecular mass ranging from 66.2 to 97.4 KDa. Compared with normal night temperature, more proteins were found in pineapple, but no difference was found in K. pinnata. Thus, above result indicated that the pineapple tonoplasts could keep higher rigidity under high night temperatures compared to the K. pinnata.

We have determined a 1778 base sequence which includes the complete ndhCKJ operon of barley plastid DNA. This operon contains the ndhC, ndhK and ndhJ genes encoding the polypeptides NDH-C, NDH-K and NDH-J, respectively, of the thylakoid Ndh complex. Poly-and mono-cistronic transcripts were identified, with an increase in the latter under oxidative stress induced by herbicide Paraquat. Complete sequencing of transcript cDNAs and of the corresponding regions of five additional monocots revealed that the 13^th C (cytosine) base of ndhC is edited to U (uracil) converting the CAC codon (encoding histidine, H) to UAC (encoding tyrosine, Y). Dicots having the appropriate TAC codon at the genome sequence do not require editing. The new editing site can not be predicted by comparison with the Marchantia sequence (that has a C at the 13^th position) because, in contrast to Angiosperms, the amino-terminal sequence in lower plants is highly variable in NDH-C.

Wheat (Triticum aestivum L.) cvs. HD 2285 (relatively tolerant) and WH 542 (susceptible) were exposed to ambient and elevated temperature (3-4 °C higher) in open top chambers during post anthesis period. The grain yield components were determined at the time of maturity. In order to elucidate the basis of differential tolerance of these cultivars, the excised developing grains (20 d after anthesis) of ambient grown plants were incubated at 15, 25, 35 and 45 °C for 2 h and then analysed for the activities of soluble starch synthase (SSS), granule bound starch synthase (GBSS), kinetic parameters of SSS and content of heat shock protein (HSP 100). The elevated temperature during grain development significantly decreased grain growth in WH 542 whereas no such decrease was observed in HD 2285. High temperature tolerance of HD 2285 was found to be associated with higher catalytic efficiency (V_max/K_m) of SSS at elevated temperature and higher content of HSP 100.

The influence of freezing treatment on plasma membrane (PM) H⁺-ATPase was investigated using plasma membrane vesicles isolated from calluses from Chorispora bungeana Fisch. & C.A. Mey. by the discontinuous sucrose gradient centrifugation. Freezing treatment (-4 °C) for 5 d resulted in significant increases in the ATPase activity and the activity of p-nitrophenyl phosphate (PNPP) hydrolysis, decreases in the K_m for ATP hydrolysis and PNPP hydrolysis, and the shift of optimal pH from 6.5 to 7.0. Also, the activity PNPP hydrolysis was less sensitive to vanadate after freezing treatment compared to control, while the inhibition of ATP hydrolysis by hydroxylamine was more sensitive. In addition, freezing treatment also decreased the activation effects of trypsin on PNPP hydrolysis, but increased the activation effects of lysophosphatidylcholine on ATP hydrolysis. Taken together, these results suggested that PM H⁺-ATPase might play an important role during adaptation to freezing and enhancing the frost hardness in C. bungeana.

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.

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 activity of chlorophyllase in wild type (WT) was higher than in ethylene insensitive mutant (eti 5) of Arabidopsis thaliana (L.) Heynh plants during the vegetative period. Chlorophyll content in eti 5 leaves was higher than in WT but the difference decreased by the end of the experimental period.

An experiment was taken up to find out possibilities of manipulating the in vitro flowering in moth bean. Abscisic acid (ABA) and proline both alone and in combination influenced days to flower induction, number of flowers per plant, number of pods per plant and seeds per pod. Frequency of flowering plants approached 100 % at 1 and 3 µM ABA and 800 µM proline. The range of flowering period (3 to 23.6 d) has also been influenced by various treatments.

Wild-abortive (WA), Honglian (HL) and Baro-II (BT) are three important cytoplasmic male sterility (CMS) types in rice. It is essential to investigate genetic mode and allelism of fertility restorer (Rf) genes and the relationship between Rf and CMS. Fertility of the all test-cross F₁ plants shows that the restorer-maintainer relationship is similar for HL-CMS and BT-CMS, while that is variance for WA-CMS and HL-CMS (or BT-CMS), respectively. Genetic analysis of Rf genes indicates that HL-or BT-CMS are controlled by single dominant Rf gene and WA-CMS is controlled by one or two pairs of dominant Rf genes, which reflects the characters of the gametophytic and sporophytic restoration CMS type. It is concluded that there are at least three Rf loci in different accessions with Rf genes for each CMS type.

The expression of genes for synthesis of auxin (iaaM and iaaH) and cytokinins (ipt) was studied in tobacco plants transformed by two Agrobacterium tumefaciens strains C 58 and LBA 4404. The strain LBA 4404 carried binary vector plasmid pCB 1334 (ipt gene) and plasmid pCB 1349 (iaaM, iaaH and ila genes). Both plasmids carried reportered gene for npt II. Obtained plants expressed incorporated genes. New proteins with molecular masses of about 74, 40, 26, 25, 21 and 17 kDa for wild plasmid pTi C58; 60, 36, 31.5, 27, 26 and 17 kDa for binary vector plasmid pCB 1334 and 74, 49, 36, 31.5, 26 and 25 kDa for binary vector plasmid pCB 1349 were found in the patterns of soluble proteins. Significant changes in the content of chlorophylls, especially chlorophyll a, were detected in the plants carrying ipt gene and in plants transformed by the wild strain C58 of A. tumefaciens. Tobacco plants expressing ipt gene and genes from T-DNA of pTi C58 plasmid were dwarf, and in comparison to the controls, they had thicker stems, and the surface of the leaf blades was reduced to 20 - 50 %. Adventitious roots, growing from the stem, were typical for transformants overproducing auxins. Regenerants and transformants expressing genes from T-DNA of plasmid pTi C58 differed in the shape of the flowers and their fertility.

Non-vernalized scions were grafted onto vernalized stocks in winter rape (Brassica napus L. var. oleifera, cv. Górczański). The grafted plants were subjected to electric current (30 V for 30 s or 6 V for 24 h) and the percentage of flowering scions was recorded. The negative polarity with cathode (-) attached to the scion and anode (+) left close to the roots inhibited greatly the percentage of flowering. The reverse polarity enhanced flowering markedly under short days and only slightly promoted flowering under long days. Attachment of electrodes without passing a current had no effect on flowering.

Clones of Plumbago zeylanica were micropropagated using nodal culture. The application of random amplified polymorphic DNA (RAPD) in assessing the genetic integrity of the micropropagated plants was evaluated by polymerase chain reaction. Twenty arbitrary decamers were used to amplify genomic DNA from in vitro and in vivo plant material to assess the genetic fidelity. All RAPD profiles from micro-propagated plants were monomorphic and similar to those of field grown mother plants. No polymorphism was detected within the micropropagated plants.

The effects of drought on growth, protein content, lipid peroxidation, superoxide dismutase (SOD), peroxidase (POX), catalase (CAT) and polyphenol oxidase (PPO) were studied in leaves and roots of Sesamum indicum L. cvs. Darab 14 and Yekta. Four weeks after sowing, plants were grown under soil moisture corresponding to 100, 75, 50 and 25 % field capacity for next four weeks. Fresh and dry masses, and total protein content in leaves and roots decreased obviously under drought. However, several new proteins appeared and content of some proteins was affected. Measurement of malondialdehyde content in leaves and roots showed that lipid peroxidation was lower in Yekta than in Darab 14. Severe stress increased SOD, POX, CAT and PPO activities in leaves and roots, especially in Yekta. According to the present study Yekta is more resistant to drought than Darab 14.

We aimed to assess the potential effects of fumigation by methyl salicylate (MeSA) on plant monoterpene production and emissions. We evaluated monoterpene production and emissions both by chromatographic and proton transfer reaction mass spectrometry at the whole plant-and leaf-scales, in MeSa-fumigated (ca. 60 mm³ m^-3 in air) and control (without MeSa fumigation) holm oak (Quercus ilex L.) plants exposed to temperatures ranging from 25 to 50 °C. The MeSa-fumigated plants showed ca. 3-4-fold greater leaf monoterpene concentrations and emission rates than the control plants between the temperatures of 25 to 45 °C.

High efficiency shoot regeneration was achieved through leaflet and cotyledon derived calli in Cassia angustifolia - an important medicinal plant. Dark brown compact callus was induced at the cut ends of the explants on Murashige and Skoog's (MS) medium augmented with 1 µM N⁶-benzyladenine (BA) + 1 µM 2,4-dichlorophenoxyacetic acid (2,4-D). Such callus pieces on transfer to cytokinins (BA or kinetin) supplemented medium differentiated shoots within 10 - 15 d. Of the two cytokinins, 5 µM BA was optimum for eliciting morphogenic response in 83.33 and 70.83 % cultures with an average of 4.16 ± 0.47 and 3.70 ± 0.56 shoots in cotyledon and leaflet derived calli, respectively. The addition of 0.5 µM α-naphthaleneacetic acid (NAA) to MS + 5 µM BA further elevated the maximum average number of shoots to 12.08 ± 1.04 and 5.37 ± 0.52 for cotyledon and leaflet calli, respectively. The excised shoots were transferred to a rooting medium containing either IAA (indole-3-acetic acid), IBA (indole-3-butyric acid) or NAA. Nearly 95 % shoots developed an average of 5.4 ± 0.41 roots on half strength MS medium supplemented with 10 µM IBA.

A short time effects of 25 and 150 µM Cu²⁺ or 50 µM methyl jasmonate (MJ) on growth of roots and leaves of Phaseolus coccineus, Allium cepa and Zea mays were investigated. Both Cu²⁺ and MJ inhibited root growth. Jasmonate synthesis inhibitors (ibuprofen, IB, salicylhydroxamic acid, SHAM, and propylgallate, PG) partially reversed the inhibitory effect of Cu²⁺ in P. coccineus, but in A. cepa this effect was not clear. Pretreatment with NADPH oxidase inhibitor (20 mM imidazole, IM), and especially ethylene inhibitor (silver thiosulphate, STS) mostly weakened Cu²⁺ effect on root growth in P. coccineus and A. cepa. The growth of P. coccineus leaves also slowed down by Cu²⁺ and this effect was partially ameliorated by IB, PG and IM, and completely by SHAM and STS. In Z. mays the effect of STS was considerably lower than that of PG and SHAM which reversed the effect of Cu²⁺. These results indicate that jasmonate, ethylene and NADPH oxidase activity may be involved in Cu²⁺ inhibitory action on the roots of dicotyledon plants, but in A. cepa only ethylene and NADPH oxidase are involved. However, leaf growth inhibition induced by excess Cu²⁺ is connected in Z. mays especially with jasmonate, and in P. coccineus with ethylene, NADPH oxidase and, to a minor degree, with jasmonate.

Embryonal axis explants from 2-d-old in vitro germinated seeds were used to induce multiple shoot production. The combination of 4.44 µM BA and 1.59 µM NAA in MS medium triggered the initiation of adventitious shoot buds. The explants with shoot buds produced maximum number of shoots (10.6 per explant) in MS medium supplemented with 4.44 µM BA and 0.065 mM L-glutamine in three successive transfers. The elongated shoots were rooted on MS medium with 4.92 µM IBA. Rooted plants were transferred to soil with a survival rate of 65 %.

An efficient protocol has been developed for rapid micropropagation of Ocimum basilicum. Multiple shoots were induced by culturing shoot tip explants excised from mature plants on a liquid Murashige and Skoog (MS) medium supplemented with 5-100 µM of thidiazuron (TDZ) for different treatment duration (4, 8, 12 and 16 d). The optimal level of TDZ supplementation to the culture medium was 50 µM for 8 d induction period followed by subculturing in MS medium devoid of TDZ as it produced maximum regeneration frequency (78 %), mean number of shoots (11.6 ± 1.16) and shoot length (4.8 ± 0.43 cm) per explant. A culture period longer than 8 d with TDZ resulted in the formation of fasciated or distorted shoots. The regenerated shoots rooted best on MS medium containing 1.0 µM indole-3-butyric acid (IBA). The micropropagated shoots with well developed roots were successfully established in pots containing garden soil and grown in greenhouse with 95 % survival rate. The regenerated plants were morphologically uniform and exhibited similar growth characteristics and vegetative morphology to the donor plants.

The ratio of activities of glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase (G6P DH/6PG DH), and the contents of glucose-6-phosphate (G6P), 6-phosphogluconate (6PG) and fructose-6-phosphate (F6P) were studied at various stages of potato virus Y (PVY) multiplication in Nicotiana tabacum cv. Samsun. G6P DH/6PG DH increased through the experiment from 0.42 to 0.53 in leaves of healthy tobacco, and up to 0.59 in PVY systemically infected leaves. However, these ratios in the ruptured protoplast preparations, and the chloroplast and cytosol fractions of healthy protoplasts were similar to that from infected ones. The ratio lower than 1, found in the healthy and/or PVY- infected leaf tissues and in the infected protoplasts as well, confirms the assumption that G6P DH is the control enzyme of oxidative pentosephosphate pathway not only in the healthy but also in the infected plants. The contents of G6P, 6PG and F6P in the period of the highest PVY multiplication were strongly decreased (to 30 - 50 % when compared with control healthy leaves) and were negatively correlated with the G6P DH and 6PG DH activities.

A protocol for in vitro propagation of Balkan endemic plant Salvia brachyodon Vandas from nodal segments was developed. 6-benzylaminopurine was more effective in axillary buds promotion when compared to thidiazuron. The rooting of regenerated shoots was induced by transferring them to the media supplemented with auxins. All tested auxins (indole-3-acetic acid, indole-3-butyric acid, and α-naphthaleneacetic acid) stimulated the rooting of S. brachyodon shoots. The acclimatization of in vitro rooted shoots was successful.

We examined the effects of repeated inbreeding on fitness components of the long-lived perennial Succisa pratensis (Dipsacaceae). Plants from six populations differing in size were used to establish lines with expected inbreeding coefficients f of 0, 0.5 and 0.75. The effects of different inbreeding levels were measured for seed set, seed mass, percentage germination and seedling relative growth rate. Seed set decreased following one generation of inbreeding and seedling growth rate decreased after two generations of inbreeding. Our study indicated that the mutational load is difficult to purge and that continued inbreeding tends to affect important traits in S. pratensis. Although the partial dominance hypothesis for inbreeding depression seems to account for the results, the overdominance hypothesis cannot be ruled out completely. Overall, we conclude that the response of a long-lived plant, such as S. pratensis, to repeated inbreeding does not differ from that of other plant species with shorter life spans, surely because the mechanisms that account for inbreeding depression are universal for all plant species.

This study describes two phenotypes of Arabidopsis thaliana (ecotype Columbia) developed in vitro under salt stress (75 mM NaCl). The phenotypes 01 and 02 appeared visibly distinguishable by rosette morphology and competence to produce flowers. Phenotype 01, sensible to salt stress, accumulated high quantities of Na⁺, showed a slight reduction in dry mass, and high protein and chlorophyll contents. Moreover, its anatomy exhibited some xeromorphic traits. Phenotype 02, clearly salt tolerant, showed a morphology similar to control plants, displaying typical phyllotactic rosette and flowering stalk production. Accumulation of Na⁺, protein and chlorophyll contents were close to control plants. Reversion experiments on NaCl free MS medium, showed a partially recovered phenotype 01. A threshold salt stress concentration that permits the simultaneous development of two phenotypes, was found.

When growing in the field, plants are exposed to the effect of heavy metals as soon as the seed comes into contact with the soil solution. Therefore, we found important to study the effect of Cd and Ni on maize exposed to these heavy metals since sowing. The aim of this work was to examine which anatomical changes are induced by continuous intoxication of young maize root system with 0.1 mM Cd and Ni, thus modifying its growth and capacity for water and nutrient uptake. Concomitantly, the effect on concentration and distribution of Cd, Ni and some essential ions (Ca, Mg, Zn, Fe, Cu and Mn) was studied.