Phototropic bending of intact and wounded potato shoots

Intact and wounded shoots of in vitro cultured potato were investigated in situ to determine how their phototropic (PT) bending capacity was affected by water availability and exogenous auxin supplementation. Wounding strongly decreased PT bending but it recovered upon supplementation of water, auxin or both. Intact shoots required neither water nor auxin, while shoot segments required both. Shoot cuttings required only water, while, like shoot segments, decapitated shoots had a strong requirement for auxin. Water supplementation was beneficial in all treatments and PT bending was not affected in cultures that were submerged in water for a short period. Sucrose and inorganic salts present in the medium strongly affected PT bending capacity of cultures, favouring combinations with lower concentrations of both. Sucrose alone strongly promoted PT bending up to a concentration of 5%. Osmotic shock induced by the addition of small volumes of highly concentrated carbohydrate solutions (sucrose, glucose or sorbitol) induced a rapid but transient decline in PT bending capacity. These results indicate that water availability is a major factor that affects PT bending in potato plantlets.This is a post-peer-review, pre-copyedit version of an article published in Plant Cell, Tissue and Organ Culture (PCTOC). The final authenticated version is available online at: [http://dx.doi.org/10.1007/s11240-017-1235-2]Plant Cell, Tissue and Organ Culture (PCTOC) (2017

In vitro propagation of selected cultivars and hybrids of Lilium sp.

Five commercial cultivars of Lilium, three of the group Orientals (Belcanto Kasandra and Sol) and two Asiatic hybrids (with yellow and orange coloured flowers) were introduced to in vitro culture conditions by culturing explants from bulb leaves on the MS medium with 3% sucrose, 0.2 mgl"1 BA and 0.05 mgl"1 NAA. The efficiency of the bulblet production (proliferation) for five cultivars was ~ 70%. The bulblet multiplication was continued on the same medium with sucrose increased to 5%. Prior to planting, bulblets were stored for two months in a cold room (+5°C) in darkness on media with 9% sucrose to breake the dormancy. The bulblet number, weight, dimensions and root production in darkness were measured. The largest bulblets (1343.35 mg) were formed by cv. Sol. Bulblets of Asiatic cultivars were much smaller than of cultivars of the group Orientals. After planting, the adaptation success was approximately 70 % on the average. Plants flowered in spring some 18 months after planting.Komercijalne sorte ljiljana, tri iz grupe Orienta (sorte Belcanto, Kasandra i Sol) i dve iz grupe Asiatic (žuta i narandžasta), su uvedene u in vitro kulturu indukovanjem pupoljaka na odsečcima listića lukovica na čvrstoj MS podlozi sa 3% saharoze, 0,2 mgl"1 BAP i 0,05 mgl1 NAA. Uspešnost indukcije pupoljaka kod svih pet sorti bila je ~ 70%. Umnožavanje lukovica nastavljeno je na istoj podlozi uz povišenu koncentraciju saharoze od 5%. Da bi se ukinula dormantnost rastenja umnoženih lukovica, kulture su pre sadnje gajene dva meseca u hladnoj komori na + 5°C, u mraku, na podlozi bez hormona i sa 9% saharoze. Na kraju ogleda izmerene su dimenzije i težina lukovica kao i razvoj korenovog sistema na njima. Najveće lukovice razvijala je sorta Sol (1345,35 mg), a najmanje žuti Asiatic (176,97 mg). Adaptacija posađenih lukovica bila je oko 90 %. Biljke su procvetale u proleće, godinu i po dana nakon sadnje.nul

In vitro propagation of selected cultivars and hybrids of Lilium sp.

Five commercial cultivars of Lilium, three of the group Orientals (Belcanto Kasandra and Sol) and two Asiatic hybrids (with yellow and orange coloured flowers) were introduced to in vitro culture conditions by culturing explants from bulb leaves on the MS medium with 3% sucrose, 0.2 mgl"1 BA and 0.05 mgl"1 NAA. The efficiency of the bulblet production (proliferation) for five cultivars was ~ 70%. The bulblet multiplication was continued on the same medium with sucrose increased to 5%. Prior to planting, bulblets were stored for two months in a cold room (+5°C) in darkness on media with 9% sucrose to breake the dormancy. The bulblet number, weight, dimensions and root production in darkness were measured. The largest bulblets (1343.35 mg) were formed by cv. Sol. Bulblets of Asiatic cultivars were much smaller than of cultivars of the group Orientals. After planting, the adaptation success was approximately 70 % on the average. Plants flowered in spring some 18 months after planting.Komercijalne sorte ljiljana, tri iz grupe Orienta (sorte Belcanto, Kasandra i Sol) i dve iz grupe Asiatic (žuta i narandžasta), su uvedene u in vitro kulturu indukovanjem pupoljaka na odsečcima listića lukovica na čvrstoj MS podlozi sa 3% saharoze, 0,2 mgl"1 BAP i 0,05 mgl1 NAA. Uspešnost indukcije pupoljaka kod svih pet sorti bila je ~ 70%. Umnožavanje lukovica nastavljeno je na istoj podlozi uz povišenu koncentraciju saharoze od 5%. Da bi se ukinula dormantnost rastenja umnoženih lukovica, kulture su pre sadnje gajene dva meseca u hladnoj komori na + 5°C, u mraku, na podlozi bez hormona i sa 9% saharoze. Na kraju ogleda izmerene su dimenzije i težina lukovica kao i razvoj korenovog sistema na njima. Najveće lukovice razvijala je sorta Sol (1345,35 mg), a najmanje žuti Asiatic (176,97 mg). Adaptacija posađenih lukovica bila je oko 90 %. Biljke su procvetale u proleće, godinu i po dana nakon sadnje.nul

Nickel hyperaccumulation in shoot cultures of Alyssum markgrafii

Shoot cultures of Alyssum markgrafii O.E. Shulz, endemic nickel hyperaccumulating species of central Balkan, were established and maintained on Murashige and Skoog medium supplemented with 0.2 mg dm(-3) benzyladenine (BA). Nickel in form of NiCl2 . 6 H2O was supplemented at 22 different concentrations ranging from 0.0001 to 15 mM but none of them was lethal to cultures. High Ni2+ concentrations (10 mM or more) arrested shoot growth which, upon transfer to Ni-free medium, commenced via axillary bud proliferation. Shoots that developed from axillary buds through the subculture manifested increased tolerance to Ni2+ expressed as shoot elongation. Shoot multiplication and dry biomass production decreased with increase of N2+ in medium. Only the accumulation of Ni2+ in tissues increased with Ni2+ content of the medium. Apart from shoot cultures, high Ni2+ accumulation was registered in undifferentiated callus cultured on medium with 0.5 mg dm(-3) BA and 0.5 mg dm(-3) naphthylacetic acid. Highest content of accumulated Ni was 2.37 mu g g(-1) (d.m.) in shoots and 2.65 mu g g(-1) (d.m.) in callus, both measured on medium with 15 mM Ni2+.nul

Nickel hyperaccumulation in shoot cultures of Alyssum markgrafii

Shoot cultures of Alyssum markgrafii O.E. Shulz, endemic nickel hyperaccumulating species of central Balkan, were established and maintained on Murashige and Skoog medium supplemented with 0.2 mg dm(-3) benzyladenine (BA). Nickel in form of NiCl2 . 6 H2O was supplemented at 22 different concentrations ranging from 0.0001 to 15 mM but none of them was lethal to cultures. High Ni2+ concentrations (10 mM or more) arrested shoot growth which, upon transfer to Ni-free medium, commenced via axillary bud proliferation. Shoots that developed from axillary buds through the subculture manifested increased tolerance to Ni2+ expressed as shoot elongation. Shoot multiplication and dry biomass production decreased with increase of N2+ in medium. Only the accumulation of Ni2+ in tissues increased with Ni2+ content of the medium. Apart from shoot cultures, high Ni2+ accumulation was registered in undifferentiated callus cultured on medium with 0.5 mg dm(-3) BA and 0.5 mg dm(-3) naphthylacetic acid. Highest content of accumulated Ni was 2.37 mu g g(-1) (d.m.) in shoots and 2.65 mu g g(-1) (d.m.) in callus, both measured on medium with 15 mM Ni2+.nul

Propagation of Chelidonium majus L. by somatic embryogenesis

Direct somatic embryogenesis in celandine (Chelidonium majus L.) was achieved in epicotyl explants of seedlings after prolonged cultivation on Murashige and Skoog medium with or without plant growth regulators. Somatic embryos developed into plantlets which entered additional cycles of somatic embryogenesis. Cultures consisting of plantlets with prolonged embryogenic potential were maintained for five years on plant growth regulator free medium. Embryos which developed into rooted plantlets could be acclimated in a glasshouse enabling thus a continuous propagation scheme to be established.nul

The effects of paraquat on cabbage (Brassica oleracea var. capitata L.) cultured in vitro

Considering the great toxicity paraquat has to a wide range of plant and animal species, including man, we have investigated the possible use of cabbage in vitro cultures as a model system suitable to study this pesticide. The main aim of this study was to investigate the effect of paraquat on growth and development of cabbage shoot cultures. Special attention was paid to the detection of eventual means by which cultures can overcome the detrimental effect of the chemical, and also to investigate if some of the genotypes coming from the breeding program have an increased tolerance to paraquat. Promising domestic genotypes PI94, P295, P6p, P44 were investigated in the rooting stage. A root induction medium containing MS inorganic salts and 5.0 mgl-1 IB A was also supplemented with Paraquat at 0.5, 2.0, 10.0, 50.0 mgl -1. Shoots were treated for 24 hours and then transferred to a hormone free medium. After 28 days we measured shoot length, number of internodes, percentage of rooting, root length and formation of laterals. Paraquat decreased all the parameters which were followed. On leaves it induced lesions. Genotypes P44 and P6p were more tolerant to paraquat then the other two genotypes. Genotype P44 was interesting since in some plants lateral shoot formation occurred

Transgenic root cultures of Gentiana punctata L.

Shoot cultures of Gentiana punctata L. were inoculated with suspension of Agrobacterium rhizogenes strain A4 M70GUS. Hairy roots which appeared 2-3 weeks later were cultured on hormone-free, liquid, WPM (Lloyd and McCown 1980) basal medium for more than 5 years (60 subcultures). Growth rate of transformed roots was higher than the growth rate of nontransformed roots. Spontaneous shoot regeneration occured only in three culture vessels in subcultures No. 40 and 42. Plants had phenotype characteristics typical for A. rhizogenes transformed plants including: wrincled leaves, short internodes, plagiotropic roots and in general their growth rate was reduced. These plants also manifested precocious formation of flower buds without vernalization and flowering under in vitro conditions. Flowers were pale yellow, the same as in the standard phenotype

Effect of irradiance, sugars and nitrogen on leaf size of in vitro grown Ceratonia siliqua L.

Carob (Ceratonia siliqua L.) has compound pinnate leaves consisting of 4 - 6 pairs of leaflets. However, in conditions of in vitro culture only one pair of leaflets develops. With increasing irradiance from 9.3 to 74.1 mu mol m(-2) s(-1), leaf area increased 5-fold. Sucrose also significantly increased leaf area and the maxima were at concentration 147 mM at high irradiance and 233.6 mM at low irradiance. Sucrose was superior to Fructose, glucose and combination of both in increasing leaf area. Decreasing concentration of KNO3 and NH4NO3 caused a 3-fold decline of leaf area.nul

Xanthones Production in Gentiana dinarica Beck Hairy Root Cultures Grown in Simple Bioreactors

The hairy root clones of Gentiana dinarica cl-B, cl-D, cl-3, and cl-14 were cultivated in parallel in diverse simple bioreactors, including temporary immersion systems RITA® (TIS RITA®), bubble column bioreactors (BCB), and Erlenmeyer flasks (EF), and evaluated for biomass production and xanthone content. The obtained results showed that TIS RITA® and BCB containing ½ MS medium with 4% sucrose provided equally good growth conditions in which the majority of the clones displayed the higher percentage of dry matter (DM%), and xanthones norswertianin-1-O-primeveroside (nor-1-O-prim) and norswertianin production than those cultivated in EF. Thin and well branched hairy root clone cl-B grown in BCB for 7 weeks was superior regarding all growth parameters tested, including growth index (19.97), dry weight (2.88 g), and DM% (25.70%) compared to all other clones. Cl-B cultured in TIS RITA® contained the highest amount of nor-1-O-prim (56.82 mg per vessel). In BCB with constant aeration, cl-B accumulated the highest norswertianin content reaching 18.08 mg/vessel. The optimized conditions for cultivation of selected G. dinarica hairy root clones in highly aerated TIS RITA® and BCB systems contribute to the development of bioreactor technology designed for the large scale commercial production of xanthones nor-1-O-prim and norswertianin