Showing papers on "Kinetin published in 2016"
01 Jan 2016
TL;DR: In hypocotyl segments of mung bean seedlings, exogenously supplied indoleacetic acid was rapidly conjugated mainly into indoleacetylaspartic acid, which was inactive in inducing ethylene production.
Abstract: In hypocotyl segments of mung bean (Phaseolus mungo L.) seedlings, exogenously supplied indoleacetic acid was rapidly conjugated mainly into indoleacetylaspartic acid, which was inactive in inducing ethylene production. Kinetin is known to stimulate indoleacetic acid-induced ethylene production. The mechanism of kinetin action on indoleacetic acid-induced ethylene production by hypocotyl segments of mung bean seedlings was studied in relation to indoleacetic acid uptake and indoleacetic acid metabolism. Kinetin enhanced indoleacetic acid uptake during the initial 2-hour incubation and markedly suppressed the conversion of indoleacetic acid to indoleacetic acid conjugates throughout the whole 7-hour incubation. As a result, there was more free indoleacetic acid and less conjugated indoleacetic acid in the segments treated with kinetin than in those receiving no kinetin. A close relationship was demonstrated between the rate of ethylene production and the level of free indoleacetic acid, which was regulated by kinetin.
84 citations
TL;DR: The results obtained in the present investigation suggest the use of elicitation as a promising alternative method to increase CPT production and cell growth in the cell suspension cultures of O. mungos.
Abstract: Production of camptothecin (CPT), an anticancer compound was enhanced in the cell suspension cultures of Ophiorrhiza mungos Linn. through elicitor treatment. Cell suspension culture was established using the friable callus tissues induced from the field grown leaf explants cultured in MS solid media supplemented with 3 % sucrose, 3 mg L−1 1-Naphthaleneacetic acid (NAA), 1 mg L−1 2,4-Dichlorophenoxyacetic acid (2,4-D) and 0.5 mg L−1 kinetin (KIN). The callus tissues were used for establishing cell suspension culture in half-strength MS (1/2X MS) liquid media supplemented with the same hormone concentration. NAA was found to be essential for the prolific growth of O. mungos cells in suspension culture. Influence of different elicitors such as yeast extract (YE) and silver nitrate (AgNO3) on cell growth, CPT accumulation and cell viability was studied and found that YE and AgNO3 caused a significant increase in biomass and CPT yield according to their concentration, incubation time and feeding time. A maximum of 13.3-fold increment in CPT production and threefold increase in cell growth were recorded in cell cultures elicited with 50 mg L−1 YE on the 10th day of incubation. Cell growth and CPT level were found to decrease in the cultures treated with high concentration of elicitors. CPT was estimated using high performance liquid chromatography (HPLC). The results obtained in the present investigation suggest the use of elicitation as a promising alternative method to increase CPT production and cell growth in the cell suspension cultures of O. mungos.
61 citations
01 Jan 2016
TL;DR: Investigations in a green and a nongreen clone of pith callus of Nicotiana tabacum suggested that growth of the callus and synthesis of chlorophyll and soluble protein are controlled by relative concentrations of sucrose and kinetin in the medium.
Abstract: Investigations were carried out on the effects of various combinations of sucrose and kinetin concentrations on growth and chlorophyll production in a green and a nongreen clone of pith callus of Nicotiana tabacum L. It was found that 2 milligrams per liter or higher amounts of kinetin induced greening in the nongreen tissue. The observations suggested that growth of the callus and synthesis of chlorophyll and soluble protein are controlled by relative concentrations of sucrose and kinetin in the medium. Kinetin was found to be inhibitory for chlorophyll synthesis in the green callus.
49 citations
TL;DR: Biologically significant developmental changes were observed during acclimation particularly in leaf micromorphology in terms of changes in stomata, veins and vein-islets, and trichomes, which helps in understanding the response by the plants towards outer environmental conditions during Acclimatization.
Abstract: In vitro propagation methods using seeds and nodal segments of a 21-year old Couroupita guianensis - a medicinally important but threatened tree have been developed. Hundred percent of the seeds germinated on half strength Murashige and Skoog (MS) medium with 2.0 mg l−1 indole-3 butyric acid (IBA). Nodal segments were found most suitable for the establishment of cultures. About 90 % explants responded and 4.1 ± 0.23 shoots per node were induced after five weeks of inoculation on MS medium +4.0 mg l−1 6-benzylaminopurine (BAP). Further shoot multiplication was achieved by repeated transfer of mother explants and subculturing of in vitro produced shoots on fresh medium. Maximum number (8.2 ± 0.17) of shoots were regenerated on MS medium with 1.0 mg l−1 each of BAP and Kinetin (Kin) + 0.5 mg l−1 α-naphthalene acetic acid (NAA) with additives (50 mg l−1 of ascorbic acid and 25 mg l−1 each of adenine sulphate, L-arginine and citric acid). The multiplied shoots rooted (4.3 ± 0.26 roots/shoot) on half strength MS medium with 2.5 mg l−1 IBA. All the shoots were rooted ex vitro when pulse treated with 400 mg l−1 of IBA for five min with an average of 7.3 ± 0.23 roots per shoot. Nearly 86 % of these plantlets were acclimatized within 7–8 weeks and successfully transferred in the field. Biologically significant developmental changes were observed during acclimation particularly in leaf micromorphology in terms of changes in stomata, veins and vein-islets, and trichomes. This study helps in understanding the response by the plants towards outer environmental conditions during acclimatization. This is the first report on micropropagation of C. guianensis, which could be used for the large-scale multiplication, restoration and conservation of germplasm of this threatened and medicinally important tree.
46 citations
TL;DR: It is shown that the choice of cytokinin combined elicitors supplementation during tissue culture noticeably influences not only multiple shoot development, but also the production of secondary metabolites without genetic modification.
46 citations
TL;DR: Effect of plant growth regulators and spermidine on somatic embryogenesis and regeneration was investigated in finger millet and the influence of exogenous sperMidine on regeneration of ‘CO(Ra)-14’ mature embryo-derived new and long-term calluses was studied.
Abstract: Effect of plant growth regulators and spermidine on somatic embryogenesis and regeneration was investigated in finger millet. Mature embryos, and 3 days old seedling-derived shoot apical meristems were cultured on Murashige and Skoog (MS) medium containing picloram, 2,4,5-trichlorophenoxyacetic acid, 2,4-dichlorophenoxyacetic acid (2,4-D) and 1-naphthaleneacetic acid. Improved embryogenesis (84.7 %) was found on MS medium containing 4.0 mg L−1 2,4-D and 0.5 mg L−1 kinetin in both explants. MS medium containing 1.5 mM spermidine along with 4.0 mg L−1 2,4-D and 0.5 mg L−1 kinetin produced highest frequency (90.4 %) of somatic embryogenesis from mature embryo derived callus in genotype ‘CO(Ra)-14’. On same medium somatic embryogenesis frequencies of ‘GPU-25’, ‘Try-1’ and ‘Piyur-2’ genotypes were 55.5, 85.3 and 58.7 %, respectively after 4 weeks of incubation in dark. MS medium containing 4.0 mg L−1 6-benzylaminopurine, 0.2 mg L−1 2,4-D and 1.5 mM spermidine was found to be optimum for shoot regeneration or somatic embryos in all four genotypes of finger millet. We also studied the influence of exogenous spermidine (2.0–4.0 mM) on regeneration of ‘CO(Ra)-14’ mature embryo-derived new and long-term (20–180 days old) calluses. Highest regeneration frequency 93.1 % and mean number of shoots 25.5 were produced on MS medium containing 3.0 mM spermidine, 4.0 mg L−1 BAP and 0.2 mg L−1 2,4-D using 60 days old callus. Regenerated shoots effectively rooted on half-strength MS medium and successfully acclimatized in soil with 100 % survival rate and they grew normally without showing any morphological variation. Genetic variation of in vitro derived plants and control plants were analyzed by RAPD markers.
38 citations
TL;DR: A new and rapid protocol for optimum callus production and complete plant regeneration has been assessed in Malaysian upland rice (Oryza sativa) cv.
38 citations
TL;DR: The benefits of the protocol described here include all-year-round application, germplasm conservation, suitability for commercial production and also for the biotechnological production of pentacyclic triterpenoids.
Abstract: This is the first attempt towards an efficient regeneration protocol for an endangered and valuable medicinal plant, Thymus persicus using in vitro callus induction and indirect organogenesis. Callus induction was performed on MS medium supplemented with different concentrations of NAA and 2,4-D, alone or in combination with BAP and KN. Maximum callus induction (100%) was achieved from internode explants cultured on MS medium fortified with 2.0 mg L-1 NAA and 0.5 mg L-1 KN. The highest frequency of shoot multiplication (96%) was observed with 2.0 mg L-1 BAP+1.0 mg L-1 NAA. The maximum number of rootlets (16.6 ± 1.4) was induced on half-strength MS medium with 0.5 and 1.0 mg L-1 IBA. Rooted plantlets were then successfully grown and acclimatized in the greenhouse with a 70-85% survival rate. The benefits of the protocol described here include all-year-round application, germplasm conservation, suitability for commercial production and also for the biotechnological production of pentacyclic triterpenoids.
37 citations
TL;DR: A reliable protocol for inducing callus formation of profuse and friable morphology in endosperm explant of B. racemosa had therefore been successfully established and was optimally produced with desirable morphology.
Abstract: Objective To induce callus from the medicinally valuable species, Barringtonia racemosa L. ( B. racemosa ) whereby the formation of callus is essential for micropropagation studies and in vitro plant secondary metabolites production. Methods The callus induction potential in B. racemosa was assessed from endosperm explant cultured on different culture media and plant hormonal treatments. Lloyd and McCown's woody plant medium and Murashige and Skoog's medium were used in the study as culture media. On the other hand, various concentrations and combinations of 2,4-dichlorophenoxyacetic acid (1.0–2.0 mg/L) and kinetin (0.5–2.5 mg/L) had been incorporated in the culture media to exert the effects of auxin and cytokinin on callus induction. Results From the present study, it was found that the profuse [(1.681 ± 0.770) g fresh weight, (0.239 ± 0.239) g dry weight] and friable callus formation was optimally produced with desirable morphology and considerable percentage of callus induction (56.70%) in endosperm explants cultured on 1.0 mg/L 2,4-dichlorophenoxyacetic acid and 1.5 mg/L kinetin in Murashige and Skoog's medium. Conclusions A reliable protocol for inducing callus formation of profuse and friable morphology in endosperm explant of B. racemosa had therefore been successfully established.
33 citations
TL;DR: The results explicitly show that low kinetin doses reduce apoptosis and protect cells from oxidative stress mediated cell death and future studies on the interaction between cytokinins and human cellular pathway targets will be intriguing.
Abstract: Modulating key dynamics of plant growth and development, the effects of the plant hormone cytokinin on animal cells gained much attention recently. Most previous studies on cytokinin effects on mammalian cells have been conducted with elevated cytokinin concentration (in the μM range). However, to examine physiologically relevant dose effects of cytokinins on animal cells, we systematically analyzed the impact of kinetin in cultured cells at low and high concentrations (1nM-10μM) and examined cytotoxic and genotoxic conditions. We furthermore measured the intrinsic antioxidant activity of kinetin in a cell-free system using the Ferric Reducing Antioxidant Power assay and in cells using the dihydroethidium staining method. Monitoring viability, we looked at kinetin effects in mammalian cells such as HL60 cells, HaCaT human keratinocyte cells, NRK rat epithelial kidney cells and human peripheral lymphocytes. Kinetin manifests no antioxidant activity in the cell free system and high doses of kinetin (500 nM and higher) reduce cell viability and mediate DNA damage in vitro. In contrast, low doses (concentrations up to 100 nM) of kinetin confer protection in cells against oxidative stress. Moreover, our results show that pretreatment of the cells with kinetin significantly reduces 4-nitroquinoline 1-oxide mediated reactive oxygen species production. Also, pretreatment with kinetin retains cellular GSH levels when they are also treated with the GSH-depleting agent patulin. Our results explicitly show that low kinetin doses reduce apoptosis and protect cells from oxidative stress mediated cell death. Future studies on the interaction between cytokinins and human cellular pathway targets will be intriguing.
30 citations
TL;DR: The rapid micropropagation method using nodal segments of a 4 year old plant has been achieved and could be successfully used for the large-scale multiplication and conservation of germplasm of this endangered plant species.
Abstract: Hemidesmus indicus is an endangered medicinal plant of Peninsular India. A rapid micropropagation method using nodal segments of a 4 year old plant has been achieved in the present study. The nodal explants (2.0–3.0 cm long) were harvested from actively growing shoots of conventionally raised plants and cultured on Murashige and Skoog (MS) medium supplemented with 2.0 mg l−1 6-benzylaminopurine (BAP). Hundred percent explants responded with 5.2 ± 0.25 cm long multiple shoots (9.0 ± 0.53) from the nodal meristems. The shoots were further multiplied enormously (272 ± 4.12 shoots per explant) by repeated subculture of mother explants and freshly induced shoot clumps on MS medium with the reduced concentrations of BAP (1.0 mg l−1), kinetin (Kin; 0.5 mg l−1) and indole-3 acetic acid (IAA; 0.1 mg l−1) within 4 weeks. Highest root induction (62.0 ± 0.54 roots per shoot) was observed on 1/4th strength MS medium supplemented with 3.0 mg l−1 indole-3 butyric acid (IBA). About 96 % shoots were rooted (45.0 ± 0.48 roots per shoot) by ex vitro methods when the cut ends of the shoots pulse treated with IBA (400 mg l−1) for 5 min. The in vitro as well as ex vitro rooted plantlets were acclimatized successfully in the greenhouse. Ex vitro rooted plantlets exhibited higher percentage (98 %) of survival as compared to the in vitro rooted plantlets (91 %) in the field conditions. There were not any observable differences between in vitro propagated and field transplanted plantlets. A comparative foliar micro-morphological study of H. indicus was conducted to understand the micro-morphological changes in the plants while shifting from in vitro to the in vivo conditions in terms of variations in stomata, venation pattern and vein density, and trichomes. The aforementioned protocol could be successfully used for the large-scale multiplication and conservation of germplasm of this endangered plant species.
TL;DR: AgNO3 was found to be suitable for obtaining a high frequency of multiple shoot production from cotyledonary node explants of cotton without phenolic secretion and can be adopted for developing transgenic plants of commercial cotton cultivars through Agrobacterium-mediated genetic transformation.
Abstract: The regeneration frequency of cotton (Gossypium spp.) is greatly influenced by its genetic makeup and recalcitrant nature. In particular, phenolic secretion is a major problem in cotton tissue culture. The present study was carried out to develop a rapid and efficient in vitro regeneration method, without phenolic secretion, from cotyledonary node explants of cotton. Multiple shoot induction was achieved after 3 wk of culture on MSB5 medium supplemented with N6-benzyl adenine (BA), kinetin (KN), thidiazuron (TDZ) (each tested at 0.5–3.0 mg L−1), Pluronic F-68 (0.1–0.6% [w/v]), or silver nitrate (AgNO3; 0.5–3.0 mg L−1). AgNO3 at 2 mg L−1 produced the greatest number of shoots (a mean of 22.2 ± 0.21 shoots per cotyledonary node explant), with no phenolic secretion. The induced shoots were healthy with intense green color and multiplied rapidly on the same medium. BA at 2.5 mg L−1 produced 10.3 ± 0.37 shoots/explant with moderate phenolic secretion. Pluronic F-68 at 0.3% produced 7.6 ± 0.28 shoots/explant along with high phenolic secretion. Individual shoots were elongated on MSB5 medium + gibberellic acid (GA3; 0.2 mg L−1; shoot length 7.8 ± 0.31 cm) and rooted on MSB5 medium + α-naphthalene acetic acid (NAA; 0.3 mg L−1; 8.3 ± 0.32 roots/shoot). Rooted plantlets were acclimatized in paper cups inside a plant growth chamber at 25°C and 70% relative humidity with a 70% survival rate. From the present study, AgNO3 was found to be suitable for obtaining a high frequency of multiple shoot production from cotyledonary node explants of cotton without phenolic secretion. The current protocol can be adopted for developing transgenic plants of commercial cotton cultivars through Agrobacterium-mediated genetic transformation.
TL;DR: The regeneration system of D. hamiltonii developed is efficient and provides a useful tool for genetic transformation in bamboo species.
Abstract: By using shoot tips as explants, various media and culture conditions for callus induction and proliferation, shoot differentiation, root induction and plantlet transplantation to develop an efficient and reliable regeneration system with Dendrocalamus hamiltonii were tested. Murashige and Skoog (MS) medium supplemented with 3 mg/l 2, 4-dichlorophenoxyacetic acid, 1 mg/l benzyladenine (BA), 500 mg/l glutamine, 500 mg/l proline, and 500 mg/l casein hydrolysate yielded the best rates of callus induction and granular-compact callus induction. MS medium supplemented with 1 mg/l BA, 0.3 mg/l kinetin and 0.3 mg/l naphthaleneacetic acid conferred the highest differentiation rate of calli. The maximum rooting rate was obtained in 1/2 MS medium supplemented with 3 mg/l indole-3-butyric acid, and the roots were long and thick. All hardened plantlets survived after transfer to an equal ratio mixture of peat, vermiculite and perlite. The regeneration system of D. hamiltonii developed is efficient and provides a useful tool for genetic transformation in bamboo species.
TL;DR: In this paper, the authors aimed to develop the cacao (Theobroma cacao L.) in vitro regeneration system through somatic embryogenesis on kinetin supplemented DKW medium and somaclonal variation assessment using SSR markers.
Abstract: This study aimed to develop the cacao ( Theobroma cacao L.) in vitro regeneration system through somatic embryogenesis on kinetin supplemented DKW medium and somaclonal variation assessment using SSR markers. Callus were initiated from basal petal and staminoid explants cultured on callus induction (CI) medium contained DKW basalt salts and kinetin:2,4-D ratios of 1:15.5, 1:7.8 or 1:3.9 and then transferred onto secondary callus growth (SCG) medium contained WPM basalt salts and kinetin:2,4-D ratios of 1:7.8 or 1:3.9. The calli were then subsequently transferred onto embryo development medium contained DKW basal salts with or without the addition of amino acids, adenine or activated charcoal for the formation of somatic embryos. Nine cacao genotypes were tested for their ability to develop somatic embryos. Results of this study indicated DKW medium supplemented with Kinetin in combination with 2,4-D effectively induced cacao somatic embryogenesis. The highest somatic embryos formation was abtained from kinetin:2,4-D ratio of 1:3.9 and 1:7.8 in CI and SCG medium respectively. Cacao genotype responses were highly explant type dependent. The developed method resulted in a high percentage of somatic embryo formation (5.6-66.7%), germination (50%) and plantlet conversion (65%) and a medium percentage of somaclonal variations based on SSRs marker analysis.
TL;DR: A simple and efficient protocol for direct in vitro shoot multiplication and plant regeneration was established for an important aromatic medicinal plant, Alpinia calcarata and the genetic fidelity of regenerated plants was evaluated by adapting to two PCR-based DNA marker techniques.
Abstract: A simple and efficient protocol for direct in vitro shoot multiplication and plant regeneration was established for an important aromatic medicinal plant, Alpinia calcarata. Preinduction of rhizome segments in medium containing 8.8 μM 6-benzylamino purine (BAP) rescued the buds from dormancy in 60% of the cultures. An average of 6.2 shoots were produced from rhizomatous bud explants on Murashige and Skoog (MS) medium supplemented with 5 μM BAP, 10 μM kinetin, and 2.5 μM α-Naphthalene acetic acid (NAA). The mother cultures retained their morphogenetic potential upto four subcultures and a maximum of 1.77-fold increase in shoot multiplication was recorded after the 3rd subculture. Rooting was simultaneously induced during subculture on shoot multiplication medium eliminating an additional step for rooting induction. Rooted plantlets were successfully acclimatized in pots in the greenhouse and subsequently established in the experimental garden without any visible symptoms of wilting and necrosis. The genetic fidelity of regenerated plants was evaluated by adapting to two PCR-based DNA marker techniques, Random Amplified Polymorphic DNA (RAPD) and Inter Simple Sequence Repeats (ISSR) which detected no variability in the in vitro multiplied plantlets of A. calcarata. This efficient method of clonal multiplication may be useful for commercial scale multiplication, and in situ and ex situ conservation of elite germplasm of A. calcarata.
TL;DR: The effects of cefotaxime, amino acids and carbon source on somatic embryogenesis and plant regeneration using mature seeds in four genotypes of foxtail millet have been studied and the ‘CO5’ gave a superior response in callus induction, somatic embryo induction and regeneration.
Abstract: The effects of cefotaxime, amino acids and carbon source on somatic embryogenesis and plant regeneration using mature seeds in four genotypes (‘CO5’, ‘CO7’, ‘TNAU43’ and ‘RS118’) of foxtail millet have been studied. The ‘CO5’ gave a superior response in callus induction, somatic embryogenesis and regeneration. The highest percentage (69.3%) of embryogenic callus induction was obtained in ‘CO5’ on Murashige and Skoog (MS) medium supplemented with 3.5 mg L−1 2,4-dichlorophenoxyacetic acid (2,4-D), 1 mg L−1 kinetin and 1 mg L−1 1-naphthaleneacetic acid (NAA). Somatic embryogenesis and shoot regeneration were influenced by amino acids, carbohydrates and cefotaxime in culture medium. Maximum response of somatic embryo induction and maturation was seen on MS medium containing 3.5 mg L−1 2,4-D, 1 mg L−1 kinetin and 1 mg L−1 NAA, 750 mg L−1 proline, 2.0 mg L−1 glycine, 150 mg L−1 arginine, 800 mg L−1 casein enzymatic hydrolyzate, 20 g L−1 each sucrose and maltose and 500 mg L−1 cefotaxime. The highest frequency of plant regeneration with 21.3 shoots was obtained in ‘CO5’ on MS medium containing 3 mg L−1 6-benzylaminopurine, 0.2 mg L−1 2,4-D, 750 mg L−1 proline, 2.0 mg L−1 glycine, 150 mg L−1 arginine and 800 mg L−1 casein enzymatic hydrolyzate. The highest response of root induction with more roots and longer roots was observed in ‘CO5’ when cultured on half-strength MS medium. The in vitro-regenerated plantlets were carefully transferred to soil cups, maintained in growth chamber for a week, hardened and grown to maturity in the field.
TL;DR: A positive correlation between peroxidase, catalase and superoxide dismutase activity and the regeneration capacity was observed, and the role of antioxidative enzymes in plant organogenesis was studied.
Abstract: Unlike garlic and onion, the regeneration of chive (Allium schoenoprasum L.), cultivated both for culinary and ornamental purposes, has not been intensively studied. The effects of the eight cytokinins and the plant basal section thickness on regeneration efficiency and subsequent plant growth were studied. Representatives of all cytokinin structural groups: isoprenoide side chain (trans-zeatin) and aromatic side chain (benziladenine, kinetin, meta-topolin) adenine derivatives, and phenylurea derivatives (thidiazuron and N-(2-chloro-4-pyridyl)-N′-phenylurea) at 0, 1, 5 or 10 μM were used. Histological analysis revealed adventitious buds formation from the leaf sheaths’ bases and the basal plate. The highest regeneration frequency (100 %) and the mean bud number per explant (20.0) were achieved with 10 μM thidiazuron (TDZ), and 5 mm-thick basal sections were the most responsive explants. Inferior shoot and root growth characteristics of plants regenerated by this treatment was avoided by exclusion or replacement of 10 μM TDZ with 5 μM kinetin (Kin) after a 4-week bud induction period, without consequences on the regeneration efficiency. In addition, a positive correlation between peroxidase, catalase and superoxide dismutase activity and the regeneration capacity was observed. All antioxidative enzymes activity changed much faster with 10 μM TDZ than with 1 μM Kin, which provoked the weakest regeneration response. Moreover, a unique peroxidase isoform was observed only in TDZ-treated explants after 3rd day of treatment. This work is useful for genetic engineering and virus-free plant production advancement, and for the knowledge expansion regarding the role of antioxidative enzymes in plant organogenesis.
TL;DR: The present study conducted to determine the efficacy of the anther culture technique on the production of in vitro haploids in the aforementioned species for which there have been no successful reports concerning by androgenesis.
Abstract: The production of large numbers of haploids is the crucial point of the dihaploidisation process. Although in vitro haploid plants were successfully produced by irradiated pollen technique in winter squash (Cucurbita maxima Duch.) and pumpkin (Cucurbita moschata Duch.), the frequency is still insufficient for using in a large-scale breeding programme. Thus, the present study was conducted to determine the efficacy of the anther culture technique on the production of in vitro haploids in the aforementioned species for which there have been no successful reports concerning by androgenesis. The anthers at uninucleate microspore stage were collected at different florescence times and then cultured on a solid MS medium supplemented by different combinations of 2,4-D (2,4-dichlorophenoxyacetic acid), BAP (6-benzylaminopurine), KN (kinetin) with the constant addition of NAA (naphthalene acetic acid) to induce callogenesis, embryogenesis and plantlet initiation. The combination of PGR, genotype and anther collection time played an important role in the androgenic response. The highest response was obtained from 57SI21 and G9 lines with the combination of 2.0 or 4.0 mg/l BAP + 0.05 mg/l NAA (E6 medium) at the first anther collection time. Plantlets were regenerated and rooted on MS medium supplemented by 0.01 mg/l IAA. In total, 74 plants were recovered and propagated with micro-cuttings. The ploidy analyses revealed that 35 plants (47.3 %) were haploid (n = 20), and the others (52.7 %) were diploid (2n = 40).
TL;DR: It was clearly shown that clonal propagation using nodal explants was effective for superior stock plant production with high Reb-A content (11.7% w/w) and no significant difference in terms of morphological, yield performance and steviol glycoside compositions between regenerants and seedlings sampled from two developmental periods.
TL;DR: An efficient protocol for plant regeneration through somatic embryogenesis was standardized using three cultivars of sugarcane and putative embryogenic calli were characterized by their creamy white, nodular and friable appearance.
Abstract: An efficient protocol for plant regeneration through somatic embryogenesis was standardized using three cultivars of sugarcane (CoJ64, CoJ83 & CoJ86). Callus cultures were established by culturing the spindle segments on Murashige and Skoog medium supplemented with 2,4-d (4.0 mg/L) and kinetin (0.5 mg/L). The embryogenic calli were transferred to different media containing various concentrations of sugars (sucrose 3, 6 % and maltose 3, 6 %), proline (560 mg/L), activated charcoal (2.0 g/L), ABA (2.0 mg/L), cefotaxime (250 ppm) and agar (1.0 and 1.6 %) for optimization of somatic embryogenesis. Embryogenic calli were characterized by their creamy white, nodular and friable appearance. Putative embryogenic calli were further confirmed through histological studies. For shoot regeneration, the embryogenic callus was transferred to MS medium supplemented with BAP (0.5 mg/L) and kinetin (0.5 mg/L). Roots were induced from the regenerated shoots by transferring to MS medium supplemented with NAA (5.0 mg/L) and high level of sucrose (70 g/L). Somatic embryogenesis and subsequent plant regeneration was found genotype dependent. Hardening of the rooted plantlets was done before transplanting to field. The hardened plantlets exhibited good survival ranging from 85 to 90 %.
TL;DR: Kinetin improves B tolerance of the studied cultivars grown under B toxicity, and the follow-up application of KN to the B stressed plants improved growth and chlorophyll content and further enhanced the mentioned antioxidant enzymes and level of H2O2, MDA and proline.
TL;DR: The present findings reveal that both N6-benzyladenine and kinetin exhibit multiple and complex actions in fibroblast cells in vitro, which show antioxidant properties and are potentially powerful agents with applications in the prevention and treatment of many diseases connected with oxidative stress in skin.
Abstract: N6-benzyladenine and kinetin are adenine-type cytokinins that play various roles in many aspects of plant development and stimulate anabolic processes in plant cells. The aim of this study was to examine the effect of N6-benzyladenine and kinetin on basic oxidative stress parameters, such as antioxidative enzyme activity, reduced glutathione and thiol group content, and lipid peroxidation. The results show a stimulatory effect of kinetin and N6-benzyladenine on antioxidative enzyme activity, as well as reduced glutathione and thiol group content. Cytokinins caused a decrease in membrane phospholipid peroxidation and exhibited protective properties against malondialdehyde production. The present findings reveal that both N6-benzyladenine and kinetin exhibit multiple and complex actions in fibroblast cells in vitro. Both show antioxidant properties and are potentially powerful agents with applications in the prevention and treatment of many diseases connected with oxidative stress in skin, for example, psoriasis.
TL;DR: A cost-effective in vitro regeneration protocol was established that enables efficient, large-scale in vitro production of S. rebaudiana for field cultivation and showed no significant difference between the two sampling periods for the plants grown in the field.
Abstract: Stevia is a natural, zero-calorie, intensively sweet extracted from the leaves of Stevia rebaudiana. Its sweet taste derives from a group of compounds known as steviol glycosides. In this study, an efficient micropropagation protocol for S. rebaudiana was developed for possible commercial implementation using Murashige and Skoog (MS) basal medium without plant growth regulators for most of the process. Direct shoot formation was achieved after cultivation of nodal segments on MS medium with or without plant growth regulators (benzyl amino purine [BAP], kinetin [KIN]) at various concentrations (0.1, 0.5, 1.0, or 2.0 mg L−1). Although all treatments produced two shoots per explants after 3 wk of culture, high concentrations of KIN and BAP (1.0 or 2.0 mg L−1) induced more callus formation. Rooting was achieved on MS medium containing 0.25 mg L−1 indole-3-acetic acid (IAA), which produced 8.1 roots per shoot after 3 wk of cultivation. After acclimatization of the regenerants in a portable greenhouse for 3 wk, all regenerants and seed-derived seedlings were transferred to field conditions for 16 wk. Steviol glycoside contents (% leaf dry weight) did not differ between leaves collected from regenerants and seed-derived plants. Rebaudioside A content ranged from 4.7 to 5.0% (w/w), while stevioside ranged from 6.4 to 6.9% (w/w). There was no significant difference between the two sampling periods (late vegetative and flowering stages) for the plants grown in the field. In this study, a cost-effective in vitro regeneration protocol was established that enables efficient, large-scale in vitro production of S. rebaudiana for field cultivation.
TL;DR: It is confirmed that SLEs can be used for somatic embryogenesis and plant regeneration.
Abstract: The effect of seaweed liquid extracts (SLEs) from Gracilaria edulis and Padina boergesenii was studied on finger millet bioassays Finger millet seeds were germinated on 0–100 % of SLEs Genotype ‘PR-202’ showed superior response with higher frequency of germination (996 %), fresh weight (11 mg seedling−1), shoot length (134 cm), root number (48), and root length (86 cm) with 60 % of G edulis extract Influence of SLEs and various phytohormones on somatic embryogenesis and regeneration of finger millet was studied Shoot apical meristem was inoculated on Murashige and Skoog (MS) medium containing 3–5 mg L−1 2,4-dichlorophenoxyacetic acid (2,4-D) or 2,4,5-trichlorophenoxyacetic acid individually or in combination of 01–10 mg L−1 kinetin or 10–40 % each SLEs of G edulis or P boergesenii was used for callus induction and somatic embryogenesis SLEs of each species were used individually at 20–60 % and 25–75 % for somatic embryogenesis and regeneration, respectively The optimum levels of either SLE were found to be 20, 40, and 50 % for callus induction, somatic embryogenesis, and regeneration from somatic embryos, respectively The MS medium containing 40 mg L−1 2,4-D and 05 mg L−1 kinetin produced 532 % somatic embryogenesis in genotype ‘PR-202’ where G edulis extract improved the somatic embryogenesis to 666 % Further, 40 % of SLEs emerged somatic embryogenesis 898 %, regeneration of embryogenic callus 963 %, and rooting of elongated shoots 974 %, respectively Well-grown plantlets were acclimatized in the greenhouse with 94 % survival rate RAPD profiles of in vitro regenerated and mother plants were similar and no somoclonal variation was detected The current study confirmed that SLEs can be used for somatic embryogenesis and plant regeneration
TL;DR: A process of organogenesis via callus with successful plantlet formation was developed for Anoectochilus elatus through in vitro-derived node, internode, and leaf explants, which resulted in well-developed plants transferred to the National Orchidarium, Yercaud, Tamil Nadu, for further maintenance and establishment under natural conditions for conservation.
Abstract: A process of organogenesis via callus with successful plantlet formation was developed for Anoectochilus elatus. Indirect organogenesis was achieved from in vitro-derived node, internode, and leaf explants. The explants were cultured on Mitra medium fortified with different concentrations and combinations of plant growth regulators such as cytokinins (N6-benzyl adenine [BA], thidiazuron [TDZ], kinetin [KN], N6-(2-isopentyl) adenine [2ip] and zeatin [ZEA]), auxins (2,4-dichlorophenoxyacetic acid [2,4-D], α-naphthalene acetic acid [NAA], indole-3-acetic acid [IAA], indole-3-butyric acid [IBA], and 4-amino-3,4,6-trichloro picolinic acid [Pic]), and additives (citric acid, trisodium citrate, peptone, coconut water, potato extract, and banana pulp). Organogenic callus proliferation was highest from internode (77.8 %), followed by node (69.7 %) and leaf explants (64.2 %), on Mitra medium supplemented with TDZ (1.0 mg L−1) and NAA (0.5 mg L−1). Organogenic callus derived from internodal explants produced an average of 41.8 shoots per explant, with average length of 2.5 cm, on Mitra medium supplemented with BA (1.0 mg L−1), NAA (0.5 mg L−1) and coconut water (10 %). In rooting experiments, a maximum of 3.2 roots per shoot was observed with an average length of 2.1 cm with 97.8% response on Mitra medium amended with AgNO3 (1.0 mg L−1). The rooted plantlets were acclimatized in a mixture of garden soil, sand, vermicompost, and used tea waste (8:4:2:1 [w/w/w/w]) in a greenhouse environment, with a 72.3% survival rate. Finally, the well-developed plants were transferred to the National Orchidarium, Yercaud, Tamil Nadu, a unit of the Botanical Survey of India, Southern Regional Centre, for further maintenance and establishment under natural conditions for conservation.
TL;DR: It is revealed that kinetin significantly improved growth and yield of rice grown in nickel contamination and could be used to increase the phytoextraction of Ni from the contaminated soil.
Abstract: The present study was conducted to evaluate the effect of kinetin on growth and yield of rice in the presence and absence of nickel contamination. Rice seedlings were dipped in kinetin solution (10(-3), 10(-4) and 10 M(-5)) for 2 hours and transplanted in pots having soil contaminated with nickel sulfate @ 130 mg kg(-1). Experiment was laid out according to completely randomized design with four replications. Results revealed that kinetin significantly improved growth and yield of rice grown in nickel contamination. Kinetin @ 10(-4) M showed maximum improvement in plant height, paddy yield, 1000 grain weight, number of tillers and panicles up to 9.76, 15.72, 11.77, 11.87, and 10.90%, respectively, as compared to plants grown in contaminated soil without kinetin. Kinetin also improved the uptake of nutrients (NPK) in straw and grain of plants grown in Ni contaminated soil. Plants treated with kinetin had more concentration of Ni in shoot but less in grain compared to plants grown in Ni contaminated soil without application of kinetin. The application of kinetin can reduce stress effect on plants through improvement in the biomass of plant. This strategy could be used to increase the phytoextraction of Ni from the contaminated soil.
TL;DR: Treatment with the halogenated derivatives increased the efficiency of PSII photochemistry and the abundance of LHCII relative to DMSO- and BAP-treated controls and demonstrated that it is possible to manipulate and fine-tune leaf longevity using synthetic aromatic cytokinin analogs.
TL;DR: The type of auxins played an important role in inducing callus tissue from shoot bud explants of Safed musliCallus induction was better evidenced on Murashige and Skoog media containing 5 mg/L 2,4-dichlorophenoxyacetic acid up to fourth subculture.
Abstract: Background: Chlorophytum borivilianum is an industrially valued medicinal crop. Propagation through seeds is not feasible because of low germination percentage and long dormancy period. Therefore, callus culture and plant regeneration can be an alternative to improve this crop production. Also, callus can serve as an alternative source of bioactive compounds. Objective: To evaluate the effect of different phytohormones on callus induction, subculture cycle, and regeneration studies of callus in C. borivilianum. Materials and Methods: Young shoot buds of C. borivilianum were inoculated on Murashige and Skoog medium fortified with 3% sucrose and different concentrations (0, 1, 5, 10, and 15 mg/L) of either naphthalene acetic acid or 2,4-dichlorophenoxyacetic acid or indole-3-acetic acid and callus induction was evaluated up to four subcultures cycles. Shoot regeneration from callus was studied on Murashige and Skoog media fortified with 6-benzylaminopurine andkinetin or thidiazuron at varied levels (0, 0.5, 1, 2, and 3 mg/L). Microshoots were rooted on Murashige and Skoog media supplemented with 1.0 mg/L indole-3-butyric acid and plantlets were acclimatized before transferred to the natural conditions. Results: Callus induction was better evidenced on Murashige and Skoog media containing 5 mg/L 2,4-dichlorophenoxyacetic acid up to fourth subculture. Callus differentiated into shoots on Murashige and Skoog media fortified with 6-benzylaminopurine or kinetin, whereas thidiazuron completely failed to regenerate shoots. Furthermore, microshoots rooted on 1.0 mg/L indole-3-butyric acid containing Murashige and Skoog media. The rooted plantlets were successfully acclimatized and established in soil with 88.3% survivability. Conclusion: The type of auxins played an important role in inducing callus tissue from shoot bud explants of Safed musli. In future, this in vitro protocol could benefit in crop improvement programs and serve as a new source of bioactive compounds from Safed musli callus tissue for various therapeutic applications. Abbreviations used: MS: Murashige and Skoog, NAA: naphthalene acetic acid, 2,4-D: 2,4-dichlorophenoxyacetic acid, IAA: indole-3-acetic acid, BAP: 6-benzylaminopurine, Kn: Kinetin, TDZ: thidiazuron, IBA: indole-3-butyric acid, RCBD: Randomized Complete Block Design, DMRT: Duncan's Multiple Range Test
TL;DR: The results showed that mass selection method could be used to produce high growth of seed, and kinetin and indole-3-acetic acid play an important role in growth of K. alvarezii.
Abstract: The use of high quality seed can support the success of the seaweed cultivation. This study was conducted to evaluate the growth performance, morphology and growth related hormone level of brown strain seaweed Kappaphycus alvarezii seed produced by mass selection. Selection was performed in the Tomini Gulf, Gorontalo, based on mass selection of seaweed seed protocol with a slight modification in cut-off 10% of the highest daily growth rate. Selection was carried out for four generations. The selected 4thgeneration of seed was then used in cultivation performance test in the Celebes Sea, North Gorontalo, for three production cycles. The results showed that the selected K. alvarezii has higher clump weight and daily growth rate, longer thallus, more number of branches, and shorter internodes compared to the unselected control and seaweed from the farmer as external control. Furthermore, total sugar content, levels of kinetin hormone and kinetin:indole-3-acetic acid ratio were higher in selected seaweeds than that of unselected control and external control. Thus, mass selection method could be used to produce high growth of seed, and kinetin and indole-3-acetic acid play an important role in growth of K. alvarezii.
TL;DR: This is the first successful report on the application of polyamines for large-scale in vitro propagation and accumulation of higher stevioside content, a potential step towards industrial production.
Abstract: This study was aimed to evaluate the synergistic effects of polyamines (PAs) and plant growth regulators (PGRs) on in vitro propagation and stevioside production in Stevia rebaudiana (Stevia). A large-scale in vitro propagation protocol was established for leaf explants on Murashige and Skoog medium (MS) supplemented with various combinations of PAs and PGRs. The synergistic combination of spermidine (Spd, 2.0 mg L−1) with 2, 4-dichlorophenoxy acetic acid (2, 4-D, 1.5 mg L−1) and 6-benzyleadenine (BA, 1.5 mg L-1) induced maximum callogenic response (91.7%). The combination of Spd (1.0 mg L−1) and BA (1.0 mg L−1) was found most effective for shoot regeneration (94.4%), mean number of shoots (14. 7), and leaves per explant (88.3). However, the combination of putrescine (Put, 2.0 mg L−1) and kinetin (Kn, 2.0 mg L−1) promoted mean shoot length (6.6 cm). Incorporation of either Spd or Put in combination with naphthalene acetic acid (NAA) or indole butyric acid (IBA) to culture media improved root organogenesis. Vigorous plantlets having optimum roots were successfully acclimatized in soil. Chromatographic data revealed that the synergism of Spd, BA, and Kn (2.0 mg L−1) enhanced stevioside content in shoots (10.20 mg/g DSB) as compared to control (3.02 mg/g DW). Furthermore, application of Put and BA (2.0 mg L−1) enhanced fresh (57.5 g L−1 FSB) and dry shoot biomass (9.03 g L−1 DSB) compared to control. In contrast, the Spd and BA (2.0 mg L−1) increased antioxidant activity (80.6%) as compared to control (55.3%). Combination of Spd, BA, and GA3 (2.0 mg L-1) enhanced the production of phenolic and flavonoid contents. This is the first successful report on the application of polyamines for large-scale in vitro propagation and accumulation of higher stevioside content, a potential step towards industrial production.