Combinations Of Plant Growth Regulators Research Articles

In Vitro Propagation, Isolation and Expression Studies of Suaeda edulis Genes Involved in the Osmoprotectants Biosynthesis

Halophytes are an excellent choice for the study of genes conferring salt tolerance to salt-sensitive plants and, they are suitable for reclamation and remediation of saline soil. We develop an <i>in vitro</i> plant propagation protocol and studies of genes involved with GB and Pro biosynthesis in Suaeda edulis. Axillary buds were used as explants and cultured in different treatments on Murashige and Skoog (MS) medium supplemented with different concentrations and combinations of plant growth regulators. The highest number of multiple shoots was on MS medium containing 1 mg/L Benzyladenine (BA) and / or 2 g/L activated carbon with 5.5 ± 06 shoots per explant. The identification and expression analysis of genes involved in glycine betaine (GB) biosynthesis were S-adenosylmethionine synthetase (<i>SAMS</i>), choline monooxygenase (<i>CMO</i>) and betaine aldehyde dehydrogenase (<i>BADH</i>), and for proline (Pro) was pyrroline 5-carboxylate synthetase (<i>P5CS</i>). These sequences shared 90–95% of identity with others plant homologous in public databases. The amino acids sequence analysis showed that all these peptides contain some of the conserved motifs of those kinds of enzymes. The qRT-PCR analysis revealed a higher expression of <i>SeBADH</i>, <i>SeCMO</i>, and, <i>SeP5CS</i> genes in the roots and leaves from plants collected in the field in contrast with from <i>in vitro</i> plants. However, the expression level of <i>SeSAMS</i> was higher only in the leaves of plants collected in the field when compared to those cultivated <i>in vitro</i>.

Callus Induction and Regeneration from Anther Cultures of Indonesian Indica Black Rice Cultivar

The assembly of superior varieties and collection of rice germplasm involves the process of selecting and storing elders that have superior genotypic properties and phenotypes. The anther culture techniques on indica black rice cultivar have a high difficulty factor to get plants, because of the low regeneration ability at the plant formation phase from the anther callus. This study aimed to investigate the influence of the cold-pretreatment time on anther, the combination of plant growth regulators (PGR’s) concentrations, and putrescine concentrations in media for the increase callus induction and plant regeneration of indica black rice. The optimization of the cold pre-treatment time was important to obtain the high-frequency callus induction, which showed that anther at the 4°C for 8 days formed the high callus induction (20%). To accelerate the callus induction, the application of 20 µM putrescine in the MS medium could produce more friable embryogenic callus for 24 days with 27% of callus formation. Generally, the optimal medium for the high frequency of callus induction contained 2 mgL−1 NAA+0.5 mgL−1 Kinetin+20 µM putrescine. Especially indica black rice cultivars, the best media to get a high plant regeneration frequency were N6 media containing the combination of 2 mgL−1 IAA and 2,5 mgL−1 Kinetin. The total callus regenerated to plantlet about 12.5%. The study of the callus induction and in-vitro plant regeneration medium for indica black rice were still important to develop to get the best result for other cultivars.

In vitro Plant Regeneration from Mature Seed Explants of Withania somnifera (L.) Dunal, an Important, Rare and Endangered Medicinal Plant

Withania somnifera (L.) Dunal a member of the Solanaceae family, is a traditional medicinal plant commonly known in India as Ashwagandha. It is used for different diseases such as hiccup, cough, rheumatism, tuberculosis, and exhibits excellent antitumor and anti-bacterial activities as well. Direct organogenesis of plants using mature seeds provides faster response and is also a time saving approach, thus the present study was conducted to investigate the optimal concentrations and combinations of plant growth regulators with MS medium for the establishment of an efficient regeneration system in W. somnifera using mature seed as an explant. Therefore, an efficient in vitro protocol for high frequency regeneration has been developed using mature seeds as explant. In the present study, the multiple shoots along with embryogenic callus induction was best seen in MS medium supplemented with BAP (1.5 mg/L) and IAA (0.5 mg/L). Furthermore, MS medium fortified with GA3 (0.3 mg/L) and IBA (3.0 mg/L) alone was suited for shoot elongation and rhizogenesis respectively. The rooted plantlets were hardened and successfully established in the soil. The establishment of a highly reproducible regeneration system would greatly influence the efforts of improvement of the hereby studied medicinal plant species through useful gene transfer technology.

Affect of growth regulators and irrigation on potato yield in unstable moistening regions

The article presents the results of studies (2014-2016) concerning the assessment of the use of growth regulators (Energia-M, Vigor Forte, Atonik Plus) in combination with irrigation in the field experiment during potato cultivation (Udacha variety). The study was conducted in the Ilek district of the Orenburg region, Krasnokholmskaya Agro-firm. The soil was residual meadow southern chernozem. According to the effectiveness of impact on potato yield in southern chernozem of the Orenburg region, the factors were as follows: irrigation provided yield increase from 40% (without fertilizers) to 65…66% (NPK + Regulators); mineral fertilizers provided yield increase from 41% (without irrigation) to 59% (with irrigation); growth regulators on optimal variants provided yield increase: Vigor Forte / Atonik (tubers + plants) - 12…13% for bogharic agriculture; 16…19% with irrigation to the corresponding mineral ground. The maximum yield of potatoes under irrigation was obtained on variants with 2-fold application of Atonic and Vigor Forte growth regulators (tubers + plants) - 44.2…44.5 t/ha, an increase to the mineral fertilizing (N100P120K100) - 17.9…18.6%. The optimum soil moisture was 70…75% FC in the irrigated area. This increased the payback of 1 kg NPK due to an increase in yield from 19.6 kg (mineral fertilizing, bogharic agriculture) to 55.6…67.2 kg of tubers (combination of NPK, irrigation and regulators). Water consumption decreased from 212 m3/t (mineral fertilizing) to 140…145 m3/t (combination of mineral fertilizers and plant growth regulators).

Inducing Variability in Rice for Enriched Iron and Zinc Content through In vitro Culture

De-husked rice of four rice varieties viz., Iratom24, BRRI dhan 58, BRRI dhan 62 and Binnatoa was used to observe their regeneration efficacy and produce somaclones. MS supplemented with different combinations of plant growth regulators; MS + 2,4-D + BAP + NAA, MS + BAP + NAA + Kn + IAA and MS + IBA were used for callus induction, shoot regeneration and root induction, respectively. Transcendent frequency of callus was obtained in BRRI dhan58 (80.95%). MS supplemented with 1.5 mg/l 2, 4-D + 0.5 mg/l BAP + 0.5 mg/l NAA was found as the best for callus induction in BRRI dhan58. Maximum nutrient of shoot was found in BRRI dhan62 (80%) followed by BRRI dhan58 (66.66%). For shoot regeneration, MS supplemented with 1.5 mg/l BAP + 0.5 mg/l NAA + 0.5 mg/l Kn + 0.5 mg/l IAA performed better compared to other growth regulator combinations were tested. The highest numbers of roots were produced in all varieties under MS + 0.5 mg/l IBA media. BRRI dhan58 showed maximum number of plants was established at field condition after hardening. A total of 11, 17, 5 and 3 tissue derived plants was established in filed condition from Iratom24, BRRI dhan58, BRRI dhan62 and Binnatoa, respectively. Among the tissue culture variants, the variant number 36 derived from Binnatoa had the highest Fe 26.93 and 21.51 mg/l and Zn 42.67 and 38.84 mg/l contents in brown and polished rice grain, respectively. This high iron coupled with zinc content rice line could be the potential breeding material for developing Fe and Zn enriched rice cultivar.

The Effects of Different Concentrations and Combinations of Plant Growth Regulators on Micropropagation Potential of Pomegranates (Punica granatum L.)

A pomegranate fruit with rich nutrient content has a great importance in terms of human health. As a result, the increase in pomegranate consumption necessitated the establishment of new gardens. For this reason, to obtain new clonal pomegranate plants in a short time, in vitro micropropagation based on tissue culture techniques is gaining importance. The aim of this study was to investigate the effects of plant growth regulators at different concentrations and combinations on the micropropagation potential of pomegranates. In this study, the different combinations of BAP (1.5-2.0-2.5 mg L 1), NAA (0.5-1.0-1.5 mg L 1) and AC (activated charcoal) (0-0.02%) concentrations were applied in both full-solid and semi-solid MS basal medium. According to the general evaluation in terms of the content of the culture medium, the best results were obtained from Medium-4 (MS+4 mg L 1 Agar + 0% AC) and Medium-3 (MS+8 mg L 1 Agar + 0% AC) that the activated charcoal was not used. In medium-4 prepared as activated charcoal-free and semi-solid, the average callus rate, the average callus size and the average number of shoots were recorded as 86.00%, 87.40 mm2 and 10.30, respectively. In medium-3 prepared as activated charcoal-free and full-solid, the average callus rate, the average callus size and the average number of shoots were recorded as 83.67%, 86.37 mm2 and 18.43, respectively. In our study, shoot regeneration occurred through indirect organogenesis. The highest shoot regeneration of pomegranate cotyledons was obtained from Medium-3 (MS+8 mg L 1 Agar + 0% AC) containing 2.0 mg L 1 BAP and 1.0 mg L 1 NAA with 43.3 shoots per explant. Results of this study, the clonal micropropagation of pomegranate genotypes and varieties determined as a result of plant breeding studies will be contributed. Keywords: Pomegranate, Plant growth regulators, Callus regeneration DOI: 10.7176/JSTR/5-12-16

English

Coffea arabica, F1 hybrid variety, Ruiru 11 is a highly sought after crop in Kenya due to its alleviated resistance to Coffee Berry Disease and Coffee Leaf Rust coupled with high yield capacity and good cup quality. Access to the variety’s planting materials is limited due to challenges with difficulty in propagation using conventional methods of seed and vegetative propagation; and somatic embryogenesis is regarded as a suitable alternative propagation method. Therefore, the current study aimed to establish an induction protocol in F1 composite hybrid Ruiru 11. The current study investigated the effects of genotype and plant growth regulators, auxins and cytokinins, on induction of embryogenic callus in two composite genotypes of C. arabica L. F1 hybrid variety Ruiru 11. Leaf explants from the F1 hybrid were cultured on half-strength Murashige and Skoog (MS) media supplemented with varied concentrations and combinations of plant growth regulators. Callus formation was evaluated weekly until the 60th day. Genotypic effects were assessed based on the difference on callus induction rates, biomass fresh weights and callus formation. The genotypes tested showed highest callus induction 88% (Code 71) and 100% (Code 93) with respect to the formation of embryogenic calli. Highest fresh weight was obtained at 0.973 ± 0.011 g in Code 71 and 0.649 ± 0.03 g in Code 93 in MS media supplemented with 2,4-D + BAP ( 0.53 + 0.11 µM). The observed results are useful in formulating the best growth regulator concentration suitable for mass in vitro propagation genotypes of Arabica coffee hybrid Ruiru 11 through callus induction in vitro of leaf explants. Key words: Somatic embryogenesis, callus, auxins, cytokinin, in vitro.

Efficient plant regeneration and callus induction from nodal and hypocotyl explants of goji berry (Lycium barbarum L.) and comparison of phenolic profiles in calli formed under different combinations of plant growth regulators

Goji berry (Lycium barbarum L.) is a fruit that has many beneficial effects (such as antidiabetic, antioxidant, anticancer, antidepressant, and immunomodulatory) on human health because of several dietary constituents such as phenolics, vitamins, carotenoids, and polysaccharides. In order to develop in vitro culture protocols for callus induction and plant regeneration from different explants of Goji plants and to compare the phenolic composition in calli of different origin, various combinations of plant growth regulators (PGRs) were applied. Various types of explants (leaf, petiole, root, hypocotyl, and node) were cultured on MS medium containing 28 different concentrations and combinations of PGRs [thidiazuron (TDZ) and naphthalene acetic acid (NAA), TDZ and indole-3-acetic acid (IAA), benzyl adenine (BA) and NAA, alone TDZ, and alone BA]. The highest mean number of shoots (23.33 ± 1.86) and percentage of shoot formation (100%) were obtained from nodal explants on medium containing 0.5 mg/l BA alone. The highest mean callus diameter was obtained from hypocotyl explants on medium containing 0.25 mg/l TDZ and 0.1 mg/l IAA (21.40 ± 0.71 mm). The amounts of selected phenolic substances were significantly different in the callus obtained from different PGRs or combinations, individually. The combination of BA/NAA significantly increased the production and accumulation of chlorogenic acid and caffeic acid. The TDZ/IAA combination, TDZ alone, and TDZ/NAA combination significantly increased vanillic acid and rutin, gallic acid, and quercetin synthesis, respectively. These outcomes indicate that different PGRs lead to the production of different kinds of secondary metabolites and affect/accelerate accumulation in the callus of goji berry. The culture protocol described in this paper could be employed for the development of novel methods for the commercial production of goji secondary metabolites.

Genetic Variability and Heritability of in vitro Chrysanthemum on Various Combination of Plant Growth Regulators

Heritability is a measure that describes the magnitude of a genetic influence on a character rather than an environmental factor. The higher the heritability value of a character, the higher the genetic variability. The aim of the study was to know the interaction between the combination of growth regulators and chrysanthemum varieties that gave the best chrysanthemum growth in vitro and analyzed the heritability of various chrysanthemum characters. The research was carried out at the In vitro Laboratory of Agronomy Department, Faculty of Agriculture, Hasanuddin University, Makassar from May to September 2016. The study used a separate plot design in the group. The main plot was a combination of growth regulator consisting of 200 ml Coconut Water, 0.5 ppm BAP + Coconut Water 100 ml, BAP 1 ppm + Coconut Water 100 ml, 2,4-D 0.5 ppm + Coconut Water 200 ml, 2,4-D 0.5 ppm + BAP 0.5 ppm + Coconut Water 100 ml, 2,4-D 0.5 ppm + BAP 1 ppm + Coconut Water 100 ml. The subplots included 8 varieties of chrysanthemum (Fiji Pink, Marimar, Pasopati, Salzieta, Solida Pelangi, Limeron, Arosuka Pelangi, Yellow Tumohon). The basic media used was MS medium. The results showed that adding 200 ml young coconut to the culture media gave the best in-vitro chrysanthemum growth in terms of shoot and root formation, shoot count, root number, and shoot height in all chrysanthemum varieties; as well as all observed characters have high heritability and genetic variability

Embryogenesis efficiency and genetic stability of Dianthus caryophyllus embryos in response to different light spectra and plant growth regulators

Carnation is an important cut flower with industrial and medicinal applications. To establish an efficient protocol without somaclonal variation for micropropagation of Dianthus caryophyllus, direct and indirect somatic embryogenesis (DSE and ISE) were investigated under six different light spectra (white, red, green, blue, red + blue and far red + red) and four combinations of different plant growth regulators (PGRs) never tested so far for carnation. The best results were achieved with 2,4-dichlorophenoxyacetic acid (2,4-D) + N-(2-chloro-4-pyridyl)-N′-phenylurea (4-CPPU) for ISE and picloram + 4-CPPU or naphthoxyacetic acid (NOA) + 6-benzylaminopurine (BAP) for DSE. The DSE method was faster (3 weeks compared to 8 weeks) and easier (no subculturing compared to two rounds of subculture with ISE methods) but the percentage of somatic embryos in the ISE method was higher compared to the DSE method. Our results showed that the highest DSE, formation of embryogenic callus, embryo maturation (generation of globular, heart and torpedo shapes) and ISE rate was observed in carnation explants exposed to blue light (450–495 nm). In contrast, green (495–570 nm), red (610–700) and far red (710–730 nm) lights caused negative effects on embryogenesis compared to white light controls (380–750 nm). For the first time, genetic stability of regenerated carnation plants was estimated using inter-simple sequence repeat (ISSR) markers. The amplified products showed 75 distinct and scorable bands, and regenerants [plants obtained by primary (PSE) and secondary SE (SSE)] were completely identical to the mother plant. Similarly, flow cytometric analysis confirmed that somatic embryo-derived plants had on average 1.53 pg nuclear DNA (2C), and all plants maintained their ploidy. In conclusion, obtained embryos under blue light were big in size and torpedo-shaped and their germination was highest compared to other light spectra. Moreover, blue light was effective for direct and indirect somatic embryogenesis in carnation without induction of somaclonal variation. An effective protocol through application of phytohormones is introduced. Blue light can be used to improve in vitro propagation of carnation by somatic embryogenesis. Genetic stability of regenerated carnation plants was confirmed using inter-simple sequence repeat (ISSR) markers.

In vitro propagation of the Chinese traditional and medicinal plant Heracleum scabridum Franch

Three explants such as stem tips, leaves and petioles of Heracleum scabridum were compared for their shoot development/differentiation ability by using different plant growth regulators (PGRs). The most effective PGRs combination for callus induction and organogenesis was determined. TDZ, Kn, Zn and IAA were used to induce multiple shoots. For indirect organogenesis (from the calli), the best response (27.25 ± 4.19 shoot per stem tips) and (18.23 ± 2.12 per leaves) were obtained in Murashige and Skoog (MS) medium fortified with 0.5 mg/l IAA and 3.0 mg/l Zn with 100, 97.3% induction rate, respectively. MS medium containing 0.5 mg/l IAA and 3.0 mg/l Zn was also found to be optimal for shoot regeneration from petioles. The highest percentage of regeneration (94.6) with mean number of shoots 17.83 ± 4.87 from petioles were produced. For direct organogenesis (from axillary bud shoot clumps), 0.1 mg/l IAA and 1.5 mg/l TDZ were found to be optimal for shoot regeneration of stem tips, with mean numbers of axillary bud shoot clumps 7.12 ± 1.23 were produced. Plantlets were transferred to soil with 95% of plants acclimatized recovered successfully.

Optimization of Hormonal Combinations for In Vitro Regeneration of Lesser Periwinkle (Vinca minor L.) and Assessment of Genetic Homogeneity

Lesser Periwinkle (Vinca minor L.) is an important source of valuable secondary metabolites. To survey the effect of different combinations of plant growth regulators on the direct regeneration of Lesser Periwinkle, axillary and lateral bud segments of V. minor were used as explants. First, for shoot multiplication, Murashige and Skoog (MS) medium were fortified with four concentrations (0, 0.5, 1, and 1.5 mg l−1) of benzylaminopurine (BAP) in combination with three concentrations (0, 0.25, and 0.5 mg l−1) of indol-3-butyric acid (IBA). Then, root induction was assessed in full- and half-strength MS medium supplemented with three concentrations of IBA (0, 0.25, and 0.5). Finally, the genetic homogeneity of the regenerated plant was subsequently assessed using 10 Inter Simple Sequence Repeat (ISSR) Markers. Higher shoot number per explant (6.50) and shoot length were obtained in MS medium containing the 1.5 mg l−1 BAP with 0.5 mg l−1 IBA and 0.5 mg l−1 BAP with 0.5 mg l−1 IBA, respectively. Moreover, the best root induction rate was observed on half-strength MS containing 1 mg l−1 IBA. PCR profiles with nine ISSR primers on the regenerated and donor plants also verified the genetic homogeneity of the regenerated plantlets. The present study introduced an efficient protocol for future large-scale propagation and production of secondary metabolites in Lesser Periwinkle.

Callus and shoot induction of leaf culture Lilium longiflorum with NAA and BAP

Abstract. Lestari NKD, Deswiniyanti NW, Astarini IA, Arpiwi LM. 2019. Callus and shoot induction of leaf culture Lilium longiflorum with NAA and BAP. Nusantara Bioscience 11: 162-165. Lilium longiflorum Thunb., an Easter lily, is a common ornamental plant used as potted plant, cut flower, cosmetic and medicine. The research on tissue culture technique to induce shoots and callus is expected to increase the yield of lilies quickly and efficiently. This study aims to determine the effect of plant growth regulator combination of Naphthalene Acetic Acid (NAA) and Benzyl Amino Purine (BAP) on the development of leaf culture and the best concentration for callus induction and shoots of lily plants. This study was conducted in a completely randomized design using leaf explants in Vacin and Went medium, with combination of NAA and BAP (0; 0.5; 1 mg..L-1 ) as the treatments. The result of the eight-week observations shows that the plant growth regulators significantly affected either in days initiation callus, days initiation of shoot, percentage of callus, percentage of shoot, diameter of callus, no of shoot and length of shoot. The combination of 1 mg.L-1 NAA and BAP had the best effect in the percentage of explants forming shoots (100%), means number of shoots (5.8), and means length of shoot (11.6 cm).

Improved protocol for the transformation of adult Citrus sinensis Osbeck ‘Tarocco’ blood orange tissues

The production of transgenic citrus plants from adult tissues is difficult because of low regeneration and transformation rates. To increase the transformation efficiency of adult citrus tissues, an improved protocol involving adult Citrus sinensis Osbeck ‘Tarocco’ blood orange tissues was developed. Explants were pre-incubated in a liquid medium prior to infection by Agrobacterium tumefaciens. Plant materials were also incubated on callus-induction medium supplemented with various combinations of cytokinin (Cyt) and kanamycin (Kan). An appropriate pre-incubation of the explants increased the transformation efficiency of adult tissues. During the callus-induction period, the Cyt type and Kan concentration had the largest and smallest effects on the transformation efficiency, respectively. The most effective combination of plant growth regulator and Kan for the transformation of ‘Tarocco’ blood orange tissues was 2 mg L−1 2-isopentenyl adenine and 50 mg L−1 Kan. The transformation efficiency under the optimized conditions was 11.7%. A Southern blot analysis confirmed the integration of the transgene. These results indicated that the transformation efficiency of adult citrus tissues can be enhanced by optimizing the transformation conditions.

New biological trends on cell and callus growth and azadirachtin production in Azadirachta indica.

Azadirachtin is an important secondary metabolite from Azadirachta indica used as a natural biopesticide. This study is the first comprehensive report concerning the influence of plant growth regulators on callus induction, cell suspension growth, and azadirachtin accumulation and production in cell suspension cultures of A. indica. We investigated the effect of plant growth regulators including different types of auxins and cytokinins and their combinations on callus induction, cell suspension growth, and azadirachtin accumulation and production. The highest percentage of callusing (100%) obtained at different combinations of plant growth regulators on MS medium supplemented with 1mg/L picloram and 2mg/L kinetin and the highest fresh weight of callus (264.50mg) was observed in MS medium containing 1.5mg/L NAA and 3mg/L kinetin. In cell suspension cultures, the maximum cell density, SCV, and PCV were 2.44 × 106cells per mL, 97.95%, and 81.46%, respectively, obtained in the MS medium containing 1.5mg/L 2,4-D and 3mg/L zeatin riboside. The highest average growth rate (0.25days) was on MS medium containing 1.5mg/L NAA and 3mg/L zeatin riboside. The MS medium supplemented with 1mg/L picloram and 2mg/L kinetin produced the highest amount of fresh cell weight (493.02g/L), dry cell weight (77.27g/L), azadirachtin accumulation (3.69mg/gDW), and azadirachtin production (285.64mg/L). The results showed that all measured indices had positive correlation with together except FCW and DCW with azadirachtin accumulation.

Induced callus from seedlings of Peganum harmala L. and studying harmine compound concentration in vitro and in vivo by GC analysis

Plant tissue culture considers a benefit biotechnological technique for scientific research especially the production of undifferentiation callus cells and regeneration through suspension or static media. The seedlings of Peganum harmala was used as a source to produce callus mass in vitro in static media through different tissue culture media supplemented by varying combinations of plant growth regulators (PGR). The result illustrates that 2 mg/l of Kinitine with 0.5 mg/l of 2, 4-D was efficient to stimulate callus induction with percent 100% in stem and root of P. harmala and this combination gave a high fresh weight, 1954 mg in root and 1170mg in stem and high dry weight in root and stem was 74.60, 60.30 respectively. In a comparative analysis through gas chromatography (GC) the stem and root in field recorded harmine concentration 56.13 and 40.95 μg respectively, which was higher than the in vitro callus induction from stem and root, which may be due to the fact that field plants have not been exposed to plant hormones with concentrations higher than the normal level, which reduced the stimulation of cells producing active compounds.

Influence of Additional Nutrients and Gelling Agents on in Vitro Response of Selected Indica Rice Varieties

Indica rice varieties are recalcitrant to culture and hence the culture media should be supplemented with additional nutrients to provide energy and osmotic potential for best in vitro response. Combinations of plant growth regulators have profound influence on callus induction and regeneration potential of the selected genotypes. In addition, concentration and choice of gelling agents also have their effect on regeneration of indica rice varieties. Impact of L-Proline, and Casein Hydrolysate on tissue culture response of selected indica rice varieties is discussed and the best choice of gelling agent and their in vitro response is elucidated.

Effects of light intensity and plant growth regulators on callus proliferation and shoot regeneration in the ornamental succulent Haworthia

BackgroundHaworthia are desert succulents belonging to the Asphodelaceae family. Haworthia species are cultivated commercially as ornamentals and some rare species are quite valuable at retail market but growth slowly and difficult to propagation. However, an efficient micropropagation protocol was remained insufficient.ResultsThe organogenic cultures obtained from inflorescence explants were cultured on Murashige and Skoog (MS) medium supplemented with various combinations of 6-benzylaminopurine (BA) and α-naphthalene acetic acid (NAA) under a light intensity of 10 μmol m−2 s−1 or 45 μmol m−2 s−1. The highest callus proliferation index (93.15%) with 1.0 mg L−1 BA + 0.1 mg L−1 NAA under a light intensity of 10 μmol m−2 s−1. The best shoot proliferation rates were on media with either 1 mg L−1 BA + 0–0.4 mg L−1 NAA (65.57–81.01%) under a light intensity of 45 μmol m−2 s−1. The highest root length (15.57 mm) and the highest rooting frequency (17 roots per shoot) were obtained when adventitious shoots were inoculated on MS medium with 0.4 mg L−1 NAA + 0.4 mg L−1 IBA. The survival rate of the transplanted plantlets was about 100%. The efficient micropropagation protocol proliferated Haworthia regenerate plants from inflorescence within 11 weeks.ConclusionsThe present study determined the best combination of light intensity and plant growth regulators (PGRs) for improved organogenesis of Haworthia during propagation by tissue culture. This optimized protocol showed light intensity is an important factor for efficient callus or shoot regeneration. These results indicate that it will be useful to optimize the light conditions for future commercial cultivation, germplasm conservation, genetic engineering and molecular biology research of this ornamental plant.

Micropropogation of Sideritis pisidica Boiss. et Heldr. Apud Bentham

Sideritis pisidica Boiss. et Heldr. Apud Bentham is known as a medicinal and aromatic plant. Sideritis pisidica Boiss. et Heldr. Apud Bentham is a plant which is endemic to Turkey and a threatened species in the Labiateae family. This species is used in folk medicine since ancient times. Micropropogation is an alternative method for rapid clonal propogation. In this study, Sideritis pisidica Boiss. et Heldr. Apud Bentham was micropropagated using MS media containing different combinations of plant growth regulators; BA (0, 0.5, 1 and 1.5 mg L‑1) and GA3 (0, 0.5, 1 and 1.5 mg L‑1) for propagation, IBA (indole-3-butyric acid) 0, 0.5, 1, 1.5 and 2 mg L‑1) for rooting. The MS medium supplemented with 0.5 mg L‑1 BA and 0.2 mg L‑1 GA3 (giberellic acid) showed highest percentage of shoot multiplication and rooted with 85.5 and 79.5% response from shoot tip explant, respectively.

A novel cost-effective medium for in vitro cultivation of Gentiana kurroo Royle using sugarcane bagasse

Objective: To develop a simple, cost effective and efficient medium by using sugarcane bagasse as a base material to replace the conventional Murashige and Skoog medium. Materials and Methods: Water extracts of sugarcane bagasse alongwith some macronutrients and plant growth regulators were gelled with 0.7% agar-agar powder. Nodal segments of G. kurroo were used as explants and inoculated in the medium and placed in growth chamber under standard conditions of light and temperature. Out of the tested combinations of plant growth regulators, 0.5 mg/l each of KN and BAP showed the excellent shoot multiplication and proliferation rate on the bagasse medium with the same potential as on the MS medium with an average of 5 or - 6 shoots / explant. In vitro rooting was obtained on half strength MS medium supplemented with IBA (0.5 mg/l) with an average length of 7-8 cm and 20-25 roots/ explant. The plants were hardened in a mixture of clay loam and farmyard manure (FYM) in 1:1(w/w) with 70-80% survival rate without any phenotypic abberations. Conclusion: The results from the present investigation indicate that sugarcane bagasse can be used as a cost effective substitute of MS medium for in vitro propagation of G.kurroo.