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 experiments were carried out with germinating maize seeds (Zea mays L.), grown 6 d in the dark at 26°C. Before germination the seeds were soaked for 4 h in solutions containing 1 mM abscisic acid (ABA), 0.1 mM N₁-(2-chloro-4-pyridyl)-N₂ phenylurea (4PU-30) and their combination. The influence of plant growth regulators on the length, fresh (FM) and dry (DM) masses, proteolytic activities and soluble protein fractions in shoots, roots and endosperm were studied. As compared to control the seedlings treated with ABA showed lower length, FM and DM of shoots and roots, and lower proteolytic activities. As a consequence of suppression of both growth and protein breakdown, these seedlings possessed higher protein content in endosperm. 4PU-30 partially decreased the ABA suppressing effects.

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.

The contents of several photosynthetic metabolites - 3-phosphoglyceric acid (3-PGA), pyruvate, nicotinamide adenine dinucleotide phosphate (NADP) and adenosine triphosphate (ATP) - were determined in leaves of cotton plants (Gossypium hirsutum L. cv. H-777) subjected to waterlogging at vegetative stage, and/or drought at the reproductive stage. In controls, soil moisture contents was kept at field capacity. One day prior to stress, the plant shoots were sprayed with 5 μM aqueous solution of indole-3-acetic acid (IAA), gibberellic acid (GA₃), benzylaminopurine (BAP), abscisic acid, and ethrel. In control plants, various growth regulators reduced contents of 3-PGA and ATP while increased contents of NADP and pyruvate. During waterlogging IAA promoted 3-PGA content, and BAP enhanced pyruvate content. During drought, GA₃ enhanced ATP and 3-PGA contents, while IAA enhanced pyruvate content.

Dedifferentiation was monitored in Rubia tinctorum L. leaves over a 14-d period after callus induction using transmission electron microscope (TEM), high performance liquid chromatography (HPLC), spectroscopy and thin layer chromatography (TLC). Photosynthetic pigment loss of leaves took 3-5 d coinciding with the first period of anthraquinone accumulation. Callus cells were discernible in the region of the vascular bundles and wounded edges of leaves after 10-14 d. Characteristic ultrastructural alterations were manifested in vacuolization, appearance of mitochondria, amount of smooth endoplasmatic reticulum and cytoplasm, caryolympha density of nuclei and cytoplasm content of cells. There were special events in the transfer cells: unequal divisions of dedifferentiated plastids and lytic activity in the cell wall. Our results show that mesophyll cells seem to be stopped at a particular level of dedifferentiation, while transfer cells embodied in veins of leaves pass through further alterations and lead to callus formation. Findings suggest that a sort of dedifferentiation drift manifests in the various cells of R. tinctorum leaves during callus induction and depending on their specialized status they achieve different levels of dedifferentiation. Approximately 4 weeks after callus induction, root growth has started from the young calli.

Using different explants of in vitro seed grown Scutellaria baicalensis Georgi plantlets, hairy roots were induced following inoculation of Agrobacterium rhizogenes strains A₄GUS, R1000 LBA 9402 and ATCC11325. The A₄GUS proved to be more competent than other strains and the highest transformation rates were observed in cotyledonary leaf explant (42.6 %). The transformed roots appeared after 15-20 d of incubation on hormone free Murashige and Skoog medium. Growth of hairy roots was assessed on the basis of total root elongation, lateral root density and biomass accumulation. Maximum growth rate was recorded in root:medium ratio 1:100 (m/v). Hairy root lines were further established in Gamborg B₅ medium and the biomass increase was maximum from 15 to 30 d. PCR, Southern hybridization and RT-PCR confirmed integration and expression of left and right termini-linked Ri T-DNA fragment of the Ri plasmid from A₄GUS into the genome of Scutellaria baicalensis hairy roots. GUS assay was also performed for further integration and expression. All the clones showed higher growth rate them non-transformed root and accumulated considerable amounts of the root-specific flavonoids. Baicalin content was 14.1-30.0 % of dry root mass which was significantly higher then that of control field grown roots (18 %). The wogonin content varies from 0.08 to 0.18 % among the hairy root clones which was also higher than in non-transformed roots (0.07 %).

Salinity induced changes in α-amylase activity in three cotton cultivars (NIAB-Karishma, NIAB-86 and K-115) was studied during germination and early seedling growth under controlled conditions. The increase in NaCl concentration resulted in the decrease in α-amylase activity and break down of starch into reducing and non-reducing sugars in all cultivars, however, it was more pronounced in NIAB-86. K-115 showed highest germination followed by NIAB-Karishma and NIAB-86.

Transformation and high efficient regeneration of transgenic plants from embryogenic calluses of Bingtang sweet orange [Citrus sinensis (L.) Osbeck] was reported. Embryogenic calluses were inoculated with Agrobacterium tumefaciens strain EHA105, harboring the binary Ti plasmid pROK II and carrying a neomycin phosphotransferase II (NPTII) gene, an intron β-glucuronidase (GUS) gene and the Arabidopsis APETALA1 (AP1) gene. Transformation treatment was with inoculation time of 30 min, co-culture of 3 d at 23 °C and supplementation of the co-culture medium with 2 mg dm^-3 acetosyringone (AS). Kanamycin (50 mg dm^-3) was effective to inhibit the growth of non-transformed calluses while it did not affect the transformed ones. The total number of transformed callus lines was 7 with 100 % embryo induction. High efficient regeneration of the transgenic embryos (88 % with 4-5 shoots per embryoid) was realized within 3 months. Integration of the transgene into the citrus genome was confirmed by histochemical GUS staining, polymerase chain reaction (PCR) analysis with AP1-specific primer and Southern blot hybridization with a 712 bp PCR fragment of AP1 as the probe.

Cell lines able to grow on media containing 50, 100, 150 or 200 mM NaCl were established from potato callus cultures by direct recurrent selection or gradual selection. In callus subjected to direct selection only small clusters of cells survived on medium with 150 or 200 mM NaCl, whereas on 100 mM small cell portions appear necrotic. When cell lines were obtained by successive subcultures on media with increased concentrations of NaCl, salt-tolerant calli were more compact and developed a greenish colour free from necrotic areas. The response of calli lines grown on media with NaCl was compared to control line. The NaCl-tolerant calli showed a decrease in relative growth rate and water content, with higher reductions in the 150 mM tolerant callus. Lipid peroxidation was increased in 50 mM and 100 mM NaCl-tolerant calli, while in 150 mM tolerant callus remained similar to 100 mM values. There was a significant increase in ascorbic acid content in 100 mM and 150 mM NaCl-tolerant calli as compared to the 50 mM, that was two-fold the value found in the control. Also, the contents of soluble and insoluble proteins increased in salt-tolerant lines. SDS-PAGE of soluble proteins showed the synthesis of specific polypeptides in the presence of NaCl in culture medium and the synthesis of a new polypeptide.

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.

An efficient and rapid regeneration protocol was developed using shoot apices from germinating seedlings of two cultivars of sorghum, SPV-462 and M35-1, as explants. A vertical slit given from the base of each dissected apex enhanced the efficiency of callusing response by two fold. MS medium containing 0.5 mg dm^-3 each of 2,4-D and kinetin was most effective in producing friable and embryogenic calli. Scanning electron microscopy of these calli detected somatic embryogenesis. Calli thus induced gave rise to approximately 42 green shoots per callus in both the genotypes when transferred to regeneration medium containing 1.5 mg dm^-3 kinetin.

In vitro propagation of an anticancerous drug synthesizing plant, Ophiorrhiza prostrata D. Don, was established through indirect somatic embryogenesis. Friable embryogenic calluses were initiated from O. prostrata leaf and internode explants on Murashige and Skoog (MS) media supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D) either alone or in combination with N⁶-benzyladenine (BA) or kinetin (KIN). Somatic embryos were developed after subculture of the friable calluses onto half strength MS media containing 0.45 or 2.26 µM 2,4-D alone or in combination with BA or KIN. Medium supplemented with 2.26 µM 2,4-D and 2.22 µM BA was optimal, supporting the production of a mean of 5.8 globular embryos. Subculture of globular embryo-bearing calluses on half strength MS medium without growth regulators produced the highest embryo frequency, and the majority of them developing to early torpedo stage. Somatic embryos underwent maturation and converted to plantlets at high frequency (90 %) on half strength MS medium supplemented with 0.44 µM BA. Somatic embryo-derived plantlets with well-developed roots were established in field conditions with a 90 % survival rate.

The aim of this research was to set up a regeneration protocol from mature explants of Prunus avium L. cv. Hedelfinger and to develop an early screening method for selection of putative somaclones based on morphological and physiological traits regulated by the spectral quality of radiation. DNA analyses of a new somaclone named HS, conducted using Inter Simple Sequence Repeat (ISSR), revealed a polymorphism between the somaclone HS and wild type propagated by microcuttings. When grown under different spectral quality of radiation, somaclone HS showed a different pattern of growth and development compared to the wild type with the main modifications related to apical dominance and chlorophyll production. Somaclone HS showed reduced apical dominance compared to the wild type. Wild type shoots grown in darkness showed chlorophyll a and b contents at levels in both cases comparable to those recorded under red radiation while HS did not retain the same capability.

The localization was determined of the triterpenoids, asiaticoside and madecassoside, in different organs of glasshouse-grown plants and cultured material, including transformed roots, of two phenotypes of Centella asiatica (L.) Urban of Malaysian origin. Methanolic extracts of asiaticoside and madecassoside were prepared for gradient HPLC analysis. The two phenotypes of C. asiatica exhibited differences in terpenoid content that were tissue specific and varied between glasshouse-grown plants and tissue culture-derived material. Terpenoid content was highest in leaves, with asiaticoside (0.79 ± 0.03 and 1.15 ± 0.10 % of dry mass) and madecassoside [0.97 ± 0.06 and 1.65 ± 0.01 %(d.m.)] in the fringed (F) and smooth leaf (S) phenotypes, respectively. Roots of the F-phenotype contained the lowest content of asiaticoside [0.12 ± 0.01 %(d.m.)], whereas petioles of S-phenotype plants contained the lowest content of asiaticoside [0.16 ± 0.01 %(d.m.)] and madecassoside [0.18 ± 0.14 %(d.m.)]. Transformed roots were induced using Agrobacterium rhizogens and their growth was maximal on Murashige and Skoog basal medium supplemented with 60 g dm^-3 sucrose. However, asiaticoside and madecassoside were undetectable in transformed roots and undifferentiated callus.

Direct somatic embryogenesis and adventitious shoot formation were successfully achieved from root explants of Centaurium erythrea Gillib. cultured on Murashige and Skoog medium with half-strength macronutrients, full-strength micronutrients and vitamins, 3 % sucrose, 0.7 % agar, 100 mg dm^-3 myo-inositol and without growth regulators. Histological studies revealed that somatic embryos were formed directly from epidermal cells and adventitious buds were developed from meristematic cells in root cortex tissues. Somatic embryos as well as adventitious shoots developed into whole plantlets.

This paper describes the effect of agar, MS basal medium strength, sucrose and polyamines on the in vitro rooting of Syzygium alternifolium realized by a two step procedure involving root initiation (RI) and root elongation (RE). RI was carried out on solidified MS medium supplemented with 1.0 mg dm^-3 indole-3-butyric acid (IBA) for 3 weeks, and RE following transfer to half-strength MS medium devoid of growth regulators for another 3 weeks. Agar and MS basal medium concentrations played important role on rooting response as well as on health of rooted shoots. Sucrose concentration was positively correlated with the rooting percentage, root number per shoot and root length. The combination of polyamines and 1.0 mg dm^-3 IBA increases rooting percentage compared to media containing only 1.0 mg dm^-3 IBA. Optimum rooting was attained with half-strength MS medium containing 1.0 mg dm^-3 IBA, 2 % sucrose, 10 µM spermine and 0.8 % agar.

The induction of haploid plants by in vitro gynogenesis is a promising practice in onion breeding. In order to increase the frequency of embryo regeneration and haploid plant production in Valcatorce INTA, Cobriza INTA and Navidena INTA cultivars, putrescine and CCC were used, either as a component of the culture media or by spraying or injecting them to the umbels. Additionally, two concentration of gellam gum were tested. A higher number of gynogenic embryos was achieved by using 7 g dm^-3 gellam gum, and this number was not affected by the addition of putrescine to the media. CCC sprayed at the umbels significantly increased the gynogenic embryo rate, which was more than three times higher than the control. Cobriza INTA showed the highest induced embryo rate (4.76 %).

This study investigated the influence of osmotic stress, induced by sorbitol and sucrose combinations, on growth and proline accumulation in callus cultures of rice (Oryza sativa L.). Dehusked mature seeds, cv. Hassawi, were induced to callus on MS medium supplemented with 4.52 µM 2,4-dichlorophenoxyacetic acid (2,4-D) and 2.32 µM 6-furfurylaminopurine (kinetin). The medium also contained 29.2, 58.4, 87.6, and 116.8 mM sucrose combined with 0, 54.9, 109.8, and 164.7 mM sorbitol. Callus formation was observed in about 35 % of the cultured seeds irrespective of the sugar treatment. An increase in callus mass was observed as sucrose concentration increased reaching a maximum growth at 87.6 mM. Callus growth was enhanced in response to 54.9 mM sorbitol but at higher concentration it was inhibitory. Best callus growth was obtained on a medium containing 54.9 mM sorbitol combined with 87.6 mM sucrose. Increasing osmotic stress, as a consequence of increasing sucrose and sorbitol concentrations, induced proline accumulation and the highest concentration of proline, 5.8 µmol g^-1(f.m.), was obtained on 164.7 mM sorbitol combined with 116.8 mM sucrose.

Withanolides-steroidal lactones, isolated from various Solanaceous plants have received considerable attention due to their potential biological activities. Five selected withanolides (withanone, withaferin A, withanolide A, withanolide B, withanolide E) were identified by HPLC-UV (DAD) - positive ion electrospray ionization mass spectroscopy in Withania somnifera (L.) Dunal cv. WSR plants and tissues cultured in vitro at different developmental phases. Cultures were established from five explants on Murashige and Skoog's medium supplemented with different plant growth regulators. Results suggest that production of withanolides is closely associated with morphological differentiation.

Plants of two cytotypes (2n=2x=20, and 2n=3x=30) of pinto peanut (Arachis pintoi Krapov. & W.C. Gregory) were regenerated through somatic embryogenesis. Embryogenic calli were induced from shoot tips or immature leaves dissected from in vitro growing plants. In the case of the diploid peanut the best somatic embryogenesis was achieved when shoot tips were cultured on Murashige and Skoog (MS) medium supplemented with 10 mg dm^-3 Picloram (PIC) and 0.1 mg dm^-3 6-benzylaminopurine (BAP) or when explants from immature leaves were cultured on MS + 10 mg dm^-3 PIC + 0.01 mg dm^-3 BAP. In the case of triploid peanut the highest number of somatic embryos was obtained when shoot tips were cultured on MS + 10 mg dm^-3 PIC + 0.01 mg dm^-3 BAP or when immature leaves were cultured on MS + 20 mg dm^-3 PIC + 0.01 mg dm^-3 BAP. Somatic embryos were converted into plants by culture on MS + 0.01 mg dm^-3 naphthaleneacetic acid + 0.01 mg dm^-3 BAP. Plants were successfully transferred to pots in greenhouse.

Anther-derived pre-embryogenic masses (PEMs) of callus, established via suspension cultures, were encapsulated to form synthetic seeds suitable for cryopreservation. The synchronised suspension culture proliferation necessitated the optimisation of plant growth regulators for different cultivars. The growth phase and density of the culture were also important as well as the exposure of cells to vitrification solution containing 0.75 M sucrose with 0.1 M CaCl₂ and 2.0 % sodium alginate (pH 5.7). Pre-treatment of the encapsulated cells for 2 d with Nitsch and Nitsch (NN) medium containing 0.75 M sucrose solution followed by dehydration for 4 h in a laminar flow box provided maximum cell viability, which varied from 0 to 40 %. The embryo proliferation from the cryopreserved beads involved warming them and then transfer to NN medium containing glutamine (50 mg dm^-3) and activated charcoal (2.5 %). The maximum number of embryos obtained was 31-53 per bead. Subculture into the same medium induced secondary embryogenesis, which was initiated from the meristematic region, radicle, and root cap. Proliferation and maturation of secondary embryos was faster than of primary embryos. No phenotypic variation or abnormal structures compared to the control were observed in the regenerated plantlets.

Effects of zinc (12-180 μM) alone and in mixtures with 12 μM Cd on metal accumulation, dry masses of roots and shoots, root respiration rate, variable to maximum fluorescence ratio (F_V/F_M), and content of photosynthetic pigments were studied in hydroponically cultivated chamomile (Matricaria recutita) plants. The content of Zn in roots and shoots increased with the increasing external Zn concentration and its accumulation in the roots was higher than that in the shoots. While at lower Zn concentrations (12 and 60 μM) the presence of 12 μM Cd decreased Zn accumulation in the roots, treatment with 120 and 180 μM Zn together with 12 μM Cd caused enhancement of Zn content in the root. Presence of Zn (12-120 μM) decreased Cd accumulation in roots. On the other hand, Cd content in the shoots of plants treated with Zn + Cd exceeded that in the plants treated only with 12 μM Cd. Only higher Zn concentrations (120 and 180 μM) and Zn + Cd mixtures negatively influenced dry mass, chlorophyll (Chl) and carotenoid content, F_V/F_M and root respiration rate. Chl b was reduced to a higher extent than Chl a.

The effects of different growth conditions (ventilated and closed vessels, medium with 0, 15 and 30 g dm^-3 sucrose) during proliferation of donor quince (Cydonia oblonga Mill.) shoots (stage I) on net photosynthetic rate and soluble sugars content were evaluated. In order to assess the influence of these physiological parameters on morphogenesis, leaf explants harvested from donor shoots were induced to form somatic embryos and adventitious roots under ventilated and closed Petri dishes (stage II). Natural ventilation and low sucrose contents (0-15 g dm^-3) promoted the photosynthetic rate of quince shoots whereas biomass accumulation was the highest in those shoots cultured with 30 g dm^-3 sucrose in both vessel types and 15 g dm^-3 sucrose under natural ventilation. Increasing sucrose content in the medium induced greater accumulation of sucrose in leaf tissues of donor shoots. The content of reducing sugars was higher than that of sucrose, and it appeared to be higher in shoots cultured under natural ventilation compared to those in closed vessels. Somatic embryogenesis and root regeneration were influenced by stage I and II treatments. A significant correlation between sucrose content in the leaves of donor shoots and the number of somatic embryos regenerated was found, suggesting that identification of biochemical and physiological characteristics of donor shoots associated with increased regeneration ability might be helpful for improving morphogenesis in plant tissue culture.

The role of glutathione (GSH) in the adaptation of wild type Arabidopsis thaliana plants to Cd stress was investigated. The nutrient solution (control or containing 50 or 100 μM Cd) was supplemented with buthionine sulfoximine (BSO; 50, 100, 500 μM, to decrease the GSH content in plants) or GSH (50, 100, 500 μM, to increase its content in plants) in order to find how GSH content could regulate Cd stress responses. BSO application did not influence plant biomass, while exogenous GSH (especially 500 μM) reduced root biomass. BSO (500μM) in combination with Cd (100 μM) increased Cd toxicity on root growth (by over 50 %), most probably due to reduced GSH content and phytochelatin (PC) accumulation (by over 96 %). On the other hand, combination of exogenous GSH (500 μM) with Cd (100 μM) was also more toxic to plants than Cd alone despite a significant increase in GSH and PC accumulation (up to 2.7 fold in the roots). This fact could indicate that the natural content of endogenous GSH in wild type A. thaliana plants is sufficient for Cd-tolerance. A decrease in this GSH content led to decreased Cd-tolerance of the plants but an increase in GSH content did not enhance Cd-tolerance, and it showed even toxic effect on the plants.

Plants are subjected to several abiotic stresses that adversely affect growth, metabolism and yield. The dynamic research in plant genetics complemented by genome sequencing has opened up avenues to address multiple problems caused by abiotic stresses. Though many drought-induced genes have been phytoengineered in a wide range of plants, the drought signal transduction pathways, and the alteration of plant sensing and signaling systems to adverse environments still remain an intriguing subject for comprehensive investigation. To impart enhanced drought tolerance in plants, a thorough perception of physiological, biochemical and gene regulatory networks is essential. Recent functional genomics tools have facilitated the progress in our understanding of stress signaling and of the linked molecular regulatory networks. This has revealed several stress-inducible genes and various transcription and signaling factors that regulate the drought stress-inducible systems. Translational genomics of these drought specific genes using model plants have provided encouraging outcomes, but the in-depth knowledge of the specific roles of various metabolites in plant stress tolerance will lead to evolvement of strategies for the phytoengineering of drought tolerance in plants in future.

In order to clarify the role of endogenous growth inhibitors A-2α and A-2β in a dwarf pea plant, red light (emission peak 657 nm) treated, 9-d-old seedlings of dwarf pea (Pisum sativum L. cv. Progress No. 9) were transferred to darkness, and the resulting changes in growth rate and concentrations of A-2α and A-2β were monitored. The growth rate of the epicotyls increased, and the concentration of the inhibitors in the epicotyls decreased, according to sigmoidal time courses. The relationship between the logarithms of the concentration of the inhibitors and the corresponding growth rate was linear. These results suggest that A-2α and A-2β, may play an important role in the growth recovery process of the dwarf pea cultivar after termination of red light irradiation.

Differences among three clones of Gentiana punctata L. hairy root shoot regenerants were investigated in relation to their growth patterns, production of secondary metabolites and 2D protein profiles. Prominent differences in growth parameters were stable thus qualifying regenerant clones as true somaclones. Marked differences in protein spots were registered among the regenerant clones but not in comparison with the non-transformed control. Southern blot hybridization of regenerants showed the absence of rolA, B and C genes, initially present in the main hairy root lines. Orf13 and rolD were present and orf8 was missing in all three regenerant clones whereas orf3 was missing only in clone 2. Although lacking the three major rol genes, plants of regenerant clones retained characteristics of the hairy root phenotype.

The present study applies RAPD technique and morphometric analysis to study the diversity of some accessions belonging to section Solanum. A total of 252 products were amplified with 23 12-mer arbitrary primer pairs, among which 210 were found to be polymorphic. Sixteen morphological characters were measured and used to compile a dendrogram. Both the morphological and RAPD marker analysis clearly separated the different accessions into similar groups. The results indicate that the analyzed cultivars with unknown origin could be derived from S. retroflexum. We found morphological differences among the S. scabrum subsp. scabrum accession which were not reflected in the molecular data. Presumably these accessions represent cultivated forms selected for their habit, fruit quantity and/or quality and leaf size, respectively.

An efficient protocol for encapsulation of nodal segments of Vitex negundo L. has been developed for the production of non-embryogenic synthetic seeds. The encapsulations of nodal segments were significantly affected by the concentrations of sodium alginate and calcium chloride. A 3 % Na₂-alginate with 100 mM CaCl₂ has been found to be optimum concentration for the production of uniform synthetic seed. For germination, the synseeds were cultured on Murashige and Skoog (MS) basal medium supplemented with kinetin (KIN) and α-naphthalene acetic acid (NAA) either singly or in various combinations. MS medium containing 2.5 μM KIN in combination with 1.0 μM NAA was found to be the optimum for maximum (92.6 ± 3.71 %) plantlet conversion frequency. Well developed regenerated plantlets were hardened, acclimatized and established in field, where they grew well without any detectable variation.

The Nicotiana tabacum transgenic plants expressing a Cucurbita pepo antisense PHYA RNA were obtained. The seedlings of transgenic tobacco with reduced phytochrome A (PHYA) content displayed decreased sensitivity to continuous broad-band far-red radiation (λ > 680 nm). Under far-red irradiance transgenic seedlings showed less elongation of the hypocotyls, more rapid plastid development, more chlorophyll accumulation, less repression of lightdependent NADPH:protochlorophyllide oxidoreductase than wild-type plants that was in accordance with PHYA control of plant development. Dynamics of the far-red radiation dependent changes in low temperature chlorophyll fluorescence spectra for the transgenic and wild-type seedlings were consistent with the more rapid formation of photosynthetic apparatus in the seedlings with reduced PHYA.