Search Results (50)

This study established an efficient in vitro regeneration system using stem nodes from root collar suckers as explants. Subsequently, regenerated shoots were used to establish an in vitro medicinal production protocol that achieved ginkgolic acid production. The self-developed Ginkgo biloba medium (GBM), first reported in this study, was pivotal to system establishment. The plantlet propagation system showed that the bases of stem nodes dipped in GBM with 2 mg·L⁻¹ 6-benzyladenine (BA) and 0.2 mg·L⁻¹ 1-naphthaleneacetic acid (NAA) achieved near-complete axillary bud induction (99.56%). Adventitious shoot induction reached 82.22% (3.5 shoots/explant) using GBM with 0.2 mg·L⁻¹ BA, 0.02 mg·L⁻¹ kinetin (Kin) and 0.2 g·L⁻¹ proline (Pro). Maximum adventitious shoot elongation (92.22%, average 3.35 cm) was observed on GBM containing 0.1 mg·L⁻¹ zeatin (ZT) and 0.01 mg·L⁻¹ BA. After 3-week preculture with 15 mg·L⁻¹ phloroglucinol (PG), treatment with 0.6 mg·L⁻¹ indole-3-butyric acid (IBA) and 0.2% activated carbon (AC) yielded 96.67% rooting (6.19 roots/explant) and 85% acclimatization survival. For medicinal resource production, bud cluster induction at 94.44% (20.89 buds/explant) on GBM with 1 mg·L⁻¹ BA, 0.03 mg·L⁻¹ Kin, and 0.2 g·L⁻¹ Pro. Leaf organs in GBM with 0.3 mg·L⁻¹ BA, 0.01 mg·L⁻¹ Kin, 0.01 mg·L⁻¹ IBA, 0.3 g·L⁻¹ Pro, and 0.01 mg·L⁻¹ glutamine (Gln) accumulated 20.64 g fresh weight and 41.910 mg·g⁻¹ DW ginkgolic acids, representing a 4.93-fold increase over mother plants. This system enables large-scale Ginkgo biloba L. propagation and provides an in vitro strategy for producing medicinal compounds in endangered plants. Full article

A pluripotent callus is central to genetic transformation in Cinnamomum parthenoxylon; however, the molecular and cellular mechanisms regulating callus formation and subsequent differentiation remain unelucidated, hindering progress in its genetic improvement. This study systematically investigated the dynamic changes during the in vitro regeneration of C. parthenoxylon through morphological observations, physiological assays, and transcriptomic analyses, while comparing differences in callus formation under varying induction conditions to elucidate the mechanism of its high-efficiency regeneration. The results showed that the formation of a pluripotent callus is a critical step in C. parthenoxylon regeneration, characterized by the presence of highly proliferative cell zones. Compared to an ordinary callus (P3C), a pluripotent callus (P3) exhibited higher activities of polyphenol oxidase (PPO) and indole-3-acetic acid oxidase (IAAO), as well as elevated levels of zeatin riboside (ZR) and abscisic acid (ABA). In contrast, P3 showed lower levels of soluble sugars, soluble proteins, malondialdehyde (MDA), indole-3-acetic acid (IAA), and gibberellins (GA), a reduced IAA/ZR ratio, and diminished peroxidase (POD) activity. Weighted gene co-expression network analysis (WGCNA) identified 27 hub transcription factors (TFs) strongly associated with IAA/ZR, primarily from the ERF, bHLH, MYB, WRKY, and C3H families. Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses revealed the significant enrichment of differentially expressed genes (DEGs) related to plant hormone signal transduction and cell wall metabolism during pluripotent callus acquisition. Further investigations revealed that five genes encoding a putative indole-3-acetic acid-amido synthetase GH3.1, protein TIFY 10A, a two-component response regulator ARR2-like isoform X2, and xyloglucan endotransglucosylase/hydrolase, likely promoting callus pluripotency by modulating plant hormone signaling and cell wall metabolism, thereby enhancing in vitro regeneration in C. parthenoxylon. In summary, this study provides critical insights into the molecular mechanisms of C. parthenoxylon regeneration and offers valuable germplasm resources for establishing an efficient and stable genetic transformation system via tissue culture. Full article

Datong in Shanxi Province, known as the “Daylily Capital of China,” still primarily relies on traditional propagation by division for daylily seedling production. Although traditional seedling propagation methods are simple and low-cost, they suffer from limitations such as low propagation efficiency, which restricts large-scale production. The application of tissue culture in seedling production not only enables rapid large-scale propagation but also helps maintain desirable genetic traits through virus elimination. This study aimed to establish an efficient in vitro regeneration system for Hemerocallis citrina ‘Datong Huanghua’ through optimization of key culture stages using scape explants. The results demonstrated that during the stages of callus induction, adventitious bud differentiation, and proliferation culture, the best results were achieved using MS medium supplemented with 3 mg/L zeatin (ZT) and 0.3 mg/L α-naphthylacetic acid (NAA), yielding a callus induction rate of 83.33%, an adventitious bud differentiation rate of 83.40%, and a proliferation coefficient of 4.05. For root induction, MS medium containing 0.25 mg/L indole-3-butyric acid (IBA) and 0.25 mg/L NAA resulted in an average of 4.7 roots per plantlet with a 100% rooting rate. In addition, endogenous hormone analysis showed that lower ABA/GA₃ and ABA/ZR ratios in scape explants promoted callus formation during the induction and differentiation stages. Full article

Catalpa bungei C.A.Mey is an economically significant deciduous tree valued for timber production and landscaping applications. An efficient regeneration system is crucial for clonal propagation and serves as a foundation for future molecular breeding in C. bungei. This study established two in vitro regeneration pathways—indirect somatic embryogenesis and shoot organogenesis utilizing mature zygotic embryos as explants. Primary callus was induced from cotyledon, hypocotyl, and plumule explants. A high frequency (45.73%) of yellow-green compact callus was achieved on De-Klerk and Walton (DKW) medium supplemented with 2.0 mg/L 6-BA, 1.0 mg/L zeatin (ZT), and 0.1 mg/L NAA. Subsequent transfer to 1.5× Murashige and Skoog (MS) medium containing 1.5 mg/L 6-BA, 0.2 mg/L ZT, and 0.1 mg/L NAA yielded the highest embryogenic callus induction rate (16.67%). Embryogenic callus demonstrated bipotent potential, generating both adventitious shoots and somatic embryos under specific hormonal conditions. Histological analyses confirmed the typical developmental stages of somatic embryos, from globular to cotyledonary forms, validating the embryogenic origin of regenerated structures. Furthermore, hormone or osmotic additives such as abscisic acid (ABA), Phytagel, and polyethylene glycol 4000 (PEG4000) significantly enhanced somatic embryo induction, with Phytagel at 5.0 g/L achieving the highest rate (76.31%). For shoot organogenesis, the optimal hormonal combination of the 0.6 mg/L 6-BA, 0.4 mg/L KT, and 0.15 mg/L NAA achieved the highest bud induction rate (88.89%) and produced an average of 4.07 adventitious buds per explant. This study presents an efficient regeneration system for C. bungei, providing a practical platform for large-scale propagation and basis for biotechnological applications in woody plants. Full article

Callicarpa peichieniana is an important traditional Chinese medicinal plant with pharmacological benefits for digestive system diseases and wounds, as well as high ornamental value. The goal of this study is to establish an effective in vitro regeneration system in order to satisfy the expanding market demand. Extracts from algae can enhance the proliferation and rooting effect of adventitious buds and can improve the survival rate of transplantation. This study developed an in vitro regeneration system using apical bud explants of C. peichieniana associated with Chlorella sorokiniana (an alga species). Inter simple sequence repeat (ISSR) molecular markers confirmed the genetic fidelity of the regenerated plantlets. The highest number of adventitious buds (5.00 buds) was induced from the apical buds with 0.5 mg/L 6-BA in a Murashige and Skoog (MS) medium, and the highest proliferation coefficient (5.83) was achieved with 2.0 mg/L 6-BA. A rooting rate of 100% was achieved by using 0.1 mg/L NAA, MS with 50% macroelements, and 20 g/L sucrose, averaging 6.36 roots per explant and a root length of 1.32 cm. In all micropropagation stages, C. sorokiniana coexisted and proliferated alongside C. peichieniana materials. ISSR showed that the genetic fidelity of C. peichieniana regenerated plants was 95.45%. Coconut coir/perlite = 1∶1 (v/v) was identified as the optimal transplantation substrate, achieving a 100% survival rate. The “C. peichieniana–C. sorokiniana association” in vitro regeneration system established in this study not only enables the mass production of high-quality regenerated plantlets but provides new ideas and demonstrations for culturing multiple species in the same in vitro system. Full article

This study established an efficient in vitro regeneration system for Tibouchina granulosato (Desr.) Cogn. petiolated leaves to address the low propagation efficiency and propagatable germplasm shortages. The results revealed that the Murashige and Skoog (MS) medium supplemented with 1.1 mg/L of Zeatin (ZT) and 0.2 mg/L of 1-naphthyl acetic acid (NAA) was the optimal formulation for callus induction, yielding callus induction of 89.59%. For adventitious bud induction, the combination of 2.0 mg/L of 6-benzyladenine (BA) and 0.4 mg/L of NAA proved most effective, achieving an induction rate of 83.33%. Additionally, the adventitious shoots exhibited remarkable elongation when cultured in a medium containing 0.2 mg/L of BA and 0.04 mg/L of NAA. All explants rooted when treated with 0.5 mg/l NAA, inducing a mean number of 6.90 roots per plant and a survival percentage of 91.00%. This study provided technical support for the promotion of superior varieties and genetic improvement of Tibouchina granulosa. Full article

Melastoma dodecandrum is primarily propagated through stem cuttings, which limits genetic variation and constrains breeding efforts. To overcome this limitation and facilitate molecular breeding, the establishment of a reliable and efficient regeneration system is essential. This study investigated the effects of plant growth regulators (PGRs) and culture media on the in vitro regeneration system of M. dodecandrum. The highest rate of callus induction (96.67%) was achieved when sterile leaf explants were cultured on Murashige and Skoog (MS) basal medium supplemented with 2.00 mg·L⁻¹ 2,4-dichlorophenoxyacetic acid (2,4-D) and 0.50 mg·L⁻¹ 6-benzylaminopurine (6-BA). For callus differentiation, the optimal formulation of MS + 2.0 mg·L⁻¹ 6-BA + 0.5 mg·L⁻¹ naphthylacetic acid (NAA) resulted in a differentiation frequency of 83.33%. The optimal PGR combinations for shoot proliferation were 1.5 mg·L⁻¹ 6-BA + 0.1 mg·L⁻¹ NAA and 0.5 mg·L⁻¹ 6-BA + 0.2 mg·L⁻¹ NAA. The optimal rooting media were MS medium supplemented with 0.1, 0.2, or 0.5 mg·L⁻¹ indole-3-butyric acid (IBA) or 1/2MS medium supplemented with 0.1 mg·L⁻¹ IBA. Additionally, this study investigated the dynamic changes in endogenous hormones during the regeneration process. The levels and ratios of hormones, including gibberellin (GA₃), abscisic acid (ABA), indole-3-acetic acid (IAA), and zeatin (ZT), collectively regulated the regeneration process. Elevated levels of ABA and GA₃ may promote callus initiation as well as the growth and development of adventitious roots during the early induction stage. Reduced levels of ABA and IAA favored callus differentiation into shoots, whereas elevated GA₃ levels facilitated proliferation of adventitious shoots. Throughout the regeneration process, fluctuations in ZT levels remained relatively stable. This study successfully established an in vitro regeneration system for M. dodecandrum using leaf explants, providing theoretical guidance and technical support for further molecular breeding efforts, genetic transformation, and industrial development. Full article

Triadica sebifera, an economically and medicinally valuable tree species native to China, was investigated for its in vitro regeneration potential using leaf explants from nodal cuttings of young stems and sprouts. This study evaluated the effects of basal media, plant growth regulators (PGRs), explant sources, and incision methods on adventitious shoot induction, supplemented by histological analysis. The highest shoot regeneration frequency (98.89%) and maximum shoot number (72) were achieved via direct organogenesis using sucker-derived nodal cuttings cultured on MS medium with 2 mg/L 6- benzyladenine (6-BA), 0.3 mg/L kinetin (KT), and 0.2 mg/L α-naphthaleneacetic acid (NAA). Under identical conditions, branch-derived explants showed lower regeneration (84.44%, 64 shoots). Transverse midvein incision proved most effective, with sucker-derived leaves exhibiting superior regeneration. Shoots elongated completely (100%) on Murashige and Skoog (MS) medium containing 0.3 mg/L 6-BA, 0.03 mg/L NAA, and activated charcoal. Rooting was optimal on MS medium with 0.3 mg/L indole-3-butyric acid (IBA), yielding a 98% acclimatization survival rate. Histological analysis revealed de novo meristem formation from parenchyma cells, confirming direct organogenesis without callus intermediation, further validating the enhanced regenerative capacity of sprout-derived explants. This efficient in vitro regeneration system provides a foundation for large-scale propagation and germplasm conservation of T. sebifera, while offering insights for woody plant regeneration studies. Full article

Philodendron ‘White Knight’ is a popular climbing evergreen plant typically propagated through stem cuttings. However, this method is slow and inefficient, making it challenging to meet the rising market demand. In vitro propagation could enhance the multiplication of this cultivar. However, research on its in vitro propagation is limited. Therefore, the objective of the present study was to establish an efficient micropropagation technique to mass-produce Philodendron ‘White Knight’ to meet the market demand. We investigate the impact of silver nanoparticles (Ag NPs) on the surface sterilization of Philodendron ‘White Knight’ petioles, the role of plant growth regulators in adventitious shoot regeneration and shoot multiplication, and the effect of auxins on the rooting ability of Philodendron ‘White Knight’ microshoots. There are few stages in plant micropropagation. The establishment of aseptic culture is the first and most important stage. For Philodendron ‘White Knight’, aseptic petiole explants (100%) were obtained after treatment with 40 mg L⁻¹ Ag NPs for 60 min. This was followed by adventitious shoot induction, and the highest rate of adventitious shoot induction (52.6%) and the maximum shoot number (13.9 shoots per petiole) were achieved on Murashige and Skoog shoot multiplication B (MS-B) medium with 20 µM of 2-isopentenyl adenine (2-IP) and 5.0 µM of naphthalene acetic acid (NAA). The shoot multiplication stage was achieved with the highest number of shoots (34 shoots per shoot tip) with a length of 5.1 cm, which was obtained on MS-B medium with 5.0 µM 2-IP and 2.5 µM NAA. All the microshoots produced roots during the root induction stage with the maximum root number (8.2 roots per shoot), and the greatest plantlet height (9.1 cm) was achieved on half-strength Murashige and Skoog medium containing indole-3-butyric acid (10.0 μM). The rooted plantlets of Philodendron ‘White Knight’ were transplanted into a substrate composed of 10% peat moss, 50% orchid stone, and 40% coconut husk chips and acclimatized in a greenhouse environment, achieving a survival rate of 100%. This micropropagation protocol can be used for the commercial production of Philodendron ‘White Knight’. Full article

Populus species are important resources for ecological conservation and certain industry productions, and are also considered model tree species for scientific research. For tree species, in vitro plant regeneration is an important method of propagation due to the advantage of high multiplication rate. Although many molecular determinants for poplar regeneration have been investigated, the complete regulatory hierarchy network remains unclear. In this study, we tracked the temporal changes of endogenous hormone contents, physiological characteristics and transcriptional profiles during callus induction and adventitious organogenesis in a stem of Populus alba L. to explore the regulatory dynamics of in vitro regeneration in poplars. The results imply that auxin may promote the formation of callus in P. alba by activating the expression of WOX11/12. By up-regulating the expression of CUC1/2, the development of callus begins to initiate apical meristem (SAM) at day 12. The cytokinin-mediated pathway regulates the adventitious shoot formation by ESR1 and WUS. The precursors of active gibberellin GA1, GA53 and GA19 were accumulated in the early stage of callus induction, and then they continued to decrease. JA may function on adventitious shoot regeneration due to its accumulation after 12 days of induction. The dominant hormonal components and regulatory factors during regeneration were identified. Based on the results, a regeneration pathway regulated by auxin and cytokinin for poplars is proposed. The key regulators identified in this study will accelerate the exploration and understanding of the asexual reproduction mechanism of poplar trees. Full article

Kalanchoe beharensis, a vulnerable species according to the International Union for Conservation of Nature, is highly prized for its ornamental value and medicinal properties. Therefore, an efficient methodology to propagate this ecologically significant species would be of particular interest. The propagation of K. beharensis has traditionally been achieved by seed or cuttings, but these methods are limited in efficiency. Micropropagation provides a more efficient and controlled alternative by enabling the in vitro production of numerous plants in a small space and in a short period of time. Despite its advantages, no micropropagation protocol for K. beharensis has been reported in the literature. In this study, we report an efficient in vitro regeneration protocol for K. beharensis. In order to implement this, we evaluated the morphogenetic response of leaf and root explants in media supplemented with auxins, cytokinins, or a combination of both growth regulators. Surprisingly, the best results were observed in indole-3-acetic acid-supplemented media. Adventitious shoots were rooted in either hormone-free or auxin-supplemented media, with indole-3-acetic acid yielding the best results. Rooted plants were acclimatized in the greenhouse, achieving over 80% survival during acclimatization. This protocol improves multiplication rate, space utilization, and uniformity, providing a viable alternative to conventional propagation methods. Full article

Actinidia kolomikta (Maxim) Maxim. is a winter-hardy species of the genus Actinidia Lindl., whose fruits are valued for their high content of vitamin C and other bioactive compounds. The use of biotechnological propagation methods significantly accelerates the production of quality planting materials for this crop. This study revealed the regeneration features of promising A. kolomikta cultivars. The main morphometric parameters of explants were determined in regard to the effect of different iron chelates (FeEDTA and FeEDDHA) and cytokinins (6-benzylaminopurine, meta-Topolin, and 2-izopentyladenine) in the Quoirin and Lepoivre medium. FeEDTA-supplemented media were optimal for explant culture. Meta-Topolin was found to promote the formation of adventitious microshoots at the base of explants and bud activation, which increased the multiplication rate by 1.5 and 1.7 times compared to the media with 6-benzylaminopurine and 2-izopentyladenine. The morpho-anatomical studies revealed the structural organization of assimilation tissues and the stomatal apparatus of A. kolomikta under different culture conditions (field, in vitro, and ex vitro). The stomata in vitro were round and had a larger area, lower thickness, and a lower layer number of mesophyll compared to field conditions. The transfer from in vitro to ex vitro caused gradual normalization of the leaf structure: a decrease in the stomatal number and area, changes in shape (from round to elliptical), and an increase in the mesophyll thickness. Full article

Paeonia ostii, a plant of substantial economic significance, continues to face constraints in achieving large-scale propagation. In vitro propagation offers a promising avenue for the production of disease-free plants and the genetic transformation of peonies to instill novel traits. However, significant challenges persist in tissue culture, particularly with regards to the reproduction coefficient of shoots and the rooting process. This study reports an efficacious protocol for P. ostii micropropagation, focusing on in vitro root development facilitated through the application of phloroglucinol (PG). Furthermore, the study unveils the molecular signature of P. ostii during in vitro root development. The results indicate that the modified Y3 medium (Y3M), supplemented with 1 mg/L 6-benzyladenine (BA) and 0.1 mg/L α-naphthaleneacetic acid (NAA), is optimal for adventitious bud induction, achieving a 96.67% induction rate and an average of 16.03 adventitious shoots per sample. The highest elongation percentage (92.15%) and the longest average shoot length (3.87 cm) were obtained with Y3M containing 0.3 mg/L BA and 0.03 mg/L NAA. Additionally, the optimal medium for inducing root formation in P. ostii was identified as WPM supplemented with 3 mg/L indole-3-butyric acid (IBA) and 100 mg/L phloroglucinol (PG). Lignin content detection, microscope inspection, and molecular signature results demonstrated that PG enhanced lignin biosynthesis, thereby promoting in vitro rooting of P. ostii. Full article

Mango (Mangifera indica L.) is one of the most significant tropical and subtropical fruit species, with high ecological and economic value. However, research on the in vitro culture of mangoes is relatively weak, so establishing an efficient and stable mango plant regeneration system is of great significance. In this study, a preliminary mango regeneration system was established with Mangifera indica L. cv. Keitt from young branches as the starting explants. The results showed that the optimal plant growth regulator (PGR) formula for direct adventitious shoot induction on the branches was 1 mg/L 6-benzylaminopurine (6-BA) + 0.1 mg/L a-naphthaleneacetic acid (NAA), with an adventitious shoot induction rate of 73.63% and an average of 6.76 adventitious shoots. The optimal basal medium for adventitious shoot induction was wood plant medium (WPM), with an adventitious shoot induction rate of 63.87% and an average of 5.21 adventitious shoots. The optimal culture medium for adventitious shoot elongation was WPM + 1 mg/L 6-BA + 0.5 mg/L NAA, with an adventitious shoot elongation rate of 89.33% and an average length of 5.17 cm. The optimal formula for the induction of mango rooting was Douglas fir cotyledon revised medium (DCR) + 3 mg/L indole-3-butyric acid (IBA), with a maximum rooting rate of 66.13% and an average rooting quantity of 6.43. The genetic fidelity of the in vitro-regenerated plants was evaluated using inter-simple sequence repeat (ISSR) molecular markers. There was no difference between the in vitro-regenerated plants and the parent plant. This study provides an efficient and stable propagation system for Mangifera indica L., laying the foundation for its rapid propagation and genetic improvement. Full article

Allium microdictyon Prokh. is a rare, endemic species possessing good taste qualities and listed in the Red Book of Kazakhstan; therefore, it is subject to anthropogenic impact (food gathering, grazing, logging, fires, etc.), which leads to a substantial reduction of its area. The aim of the study was to develop a protocol for microclonal propagation of A. microdictyon. Mature seeds of A. microdictyon collected from natural habitats in the Kazakhstani Altai were used as explants. Optimization of seed sterilization methods, selection of growth regulators for inducing adventitious shoot formation and microclonal propagation, and optimization of conditions for adaptation of regenerants to ex vitro conditions were carried out. Surface sterilization of seeds with 70% EtOH and 0.01% HgCl₂ is optimal for obtaining sterile and viable A. microdictyon seedlings. Sterile seedlings obtained in vitro on ½ Murashige and Skoog medium supplemented with 10 mg L⁻¹ gibberellic acid and 0.1 mg L⁻¹ indole-3-acetic acid (IAA) were used as a source for obtaining micropropagation cultures. Induction of adventitious organogenesis of A. microdictyon was effective on media containing 0.5 mg L⁻¹ 6-benzylaminopurine (BAP) and 1.5–2 mg L⁻¹ zeatin. On these variants, leaf conglomerates consisting of abundantly overgrown thin leaves were formed. The effect of 0.2 mg L⁻¹ indole-3-butyric acid (IBA) on further development of organogenesis and formation of microbulbs in A. microdictyon was shown in comparison with IAA, NAA, and PAC. Regenerated A. microdictyon plants were adapted to ex vitro conditions and resumed growth after 16–20 weeks of relative dormancy. The developed micropropagation protocol can be used to preserve germplasm and propagate for subsequent restoration of A. microdictyon populations in natural habitats. Full article