Plant Tissue Culture Research Articles

Production of Polyphenolic Natural Products by Bract-Derived Tissue Cultures of Three Medicinal Tilia spp.: A Comparative Untargeted Metabolomics Study

Medicinal plant tissue cultures are potential sources of bioactive compounds. In this study, we report the chemical characterization of the callus cultures of three medicinal Tilia spp. (Tilia cordata, Tilia vulgaris and Tilia tomentosa), along with the comparison to bracts and flowers of the same species. Our aim was to show that calli of Tilia spp. are good alternatives to the calli of T. americana for the production of polyphenols and are better sources of a subset of polyphenolic metabolites, compared to the original organs. Calli were initiated from young bracts and grown on woody plant medium containing 1 mg L−1 2,4-D and 0.1 mg L−1 BAP. For chemical characterization, a quality-controlled untargeted metabolomics approach and the quantification of several bioactive compounds was performed with the use of LC-ESI-MS/MS. While bracts and flowers contained flavonoid glycosides (astragalin, isoquercitrin) as major polyphenols, calli of all species contained catechins, coumarins (fraxin, esculin and scopoletin) and flavane aglyca. T. tomentosa calli contained 5397 µg g DW−1 catechin, 201 µg g DW−1 esculin, 218 µg g DW−1 taxifolin and 273 µg g DW−1 eriodictyol, while calli from other species contained lower amounts. T. cordata and T. tomentosa flowers were rich in isoquercitrin, containing 8134 and 6385 µg g DW−1, respectively. The currently tested species contained many of the bioactive metabolites described from T. americana. The production of catechin was shown to be comparable to the most efficient tissue cultures reported. Flowers and bracts contained flavonoid glycosides, including tiliroside, resembling bioactive fractions of T. americana. In addition, untargeted metabolomics has shown fingerprint-like differences among species, highlighting possible chemotaxonomic and quality control applications, especially for bracts.

New Understanding of Meta-Topolin Riboside Metabolism in Micropropagated Woody Plants.

Topolin cytokinins have emerged as valuable tools in micropropagation. This study investigates the metabolism of meta-topolin riboside (mTR) in three distinct tree species: Handroanthus guayacan and Tabebuia rosea (Bignoniaceae), and Tectona grandis (Lamiaceae). Employing labeled N15 mTR, we unraveled the complex mechanisms underlying cytokinin homeostasis, identifying N9-glucosylation as the principal deactivation pathway. Our findings demonstrate a capacity in T. rosea and H. guayacan to reposition the hydroxyl group on the cytokinin molecule, a previously unexplored metabolic pathway. Notably, this study reveals remarkable interfamilial and interspecies differences in mTR metabolism, challenging established perspectives on the role of callus tissue in cytokinin storage. These insights not only illuminate the metabolic intricacies of mTR, a cytokinin with interesting applications in plant tissue culture, but also enhances our understanding of cytokinin dynamics in plant systems, thereby enriching the scientific discourse on plant physiology and cytokinin biology.

Assessment of Semi-autotrophic Hydroponics on in vitro propagated Jamaican Sweet Yam (Dioscorea alata) - Analysis of Variance and Principal Component Analysis

Objective: Despite its benefits, plant tissue culture tends to incur a high production cost hence the need for cost-reduction strategies, especially with regards to acclimatization. One such strategy is to use semi-autotrophic hydroponics (SAH). SAH is a novel, low-cost technology that has been designed for the high-ratio and rapid propagation of clonal or vegetatively propagated crops. Sweet yam is a major export commodity of Jamaica and there is need to produce disease-free plants that require less pampering during hardening. The aim of this study is to analyze SAH in tissue culture of Jamaican sweet yams. Methods: Rooted sweet yam (Dioscorea alata) in vitro cultures were transferred to a commercial sphagnum peat moss based potting substrate, with vermiculite and fine calcitic and dolomitic limestone and the SAH system was run in a growth chamber at a tissue culture facility. Six tissue culture yam plantlets were incubated in polypropylene vessels and placed on separate shelves with north facing rows and south facing rows. Samples were treated with commercial fertilizer and controls were treated with tap water. Results: Fertilized plants showed significantly higher mean number of nodes (8.0±2.2 and 7.5±1.8) compared to non-fertilized plants (4.0±0.9 and 5.0±2.1) and significantly higher maximum leaf area index (41.42±15.49cm2 and 35.58±16.93cm2) versus non-fertilized plants (19.17±6.42cm2 and 23.58±6.55cm2). Fertilizer significantly reduced the mean number of mini tubers per plant (0.67±0.52). Non-fertilized (control) produced 2.50±1.05 and 1.83±0.41 mini tubers per plant. The mean mini tuber yields per plant were significantly reduced from 1.05±0.26g and 1.00±0.83g in non-fertilized (controls) to 0.28±0.30g and 0.34±0.40g in fertilized treatments. Principal Component Analysis (PCA) revealed three principal components accounting for 81.47% of the observed variance. PC1, 2 and 3 accounted for 39.28%, 30.49% and 11.64% of the variance respectively. PC1 described factors responsible for the vegetative growth, PC2 factors for mini tuberization and PC3 effects due to positioning of plants on shelves. Conclusion: SAH is a very flexible and adaptable technique which was found to be very useful in the acclimatization of tissue culture for Jamaican sweet yam plants. Commercial fertilizer application was found to be an efficient means of nutrient addition to promote vegetative growth. Fertilizer application significantly increased the number of nodes and maximum leaf area while it significantly reduced tuber quantity and yield. The ANOVA and PCA showed that fertilizer application was positively correlated to vegetative production factors while it was negatively correlated to mini tuber yield.

Maintenance of callus-associated endophyte balance to mitigate oxidative browning in plant tissue culture practices

Maintenance of callus-associated endophyte balance to mitigate oxidative browning in plant tissue culture practices

INCREASING SOME FLAVONOIDS COMPOUNDS FOR ECHINACEA PURPUREA L. USING COPPER OXIDE NANOPARTICLES IN VITRO.

This study was aimed to increase some flavonoids active compounds production in Echinacea purpurea seedlings through plant seeds treatment with different concentrations of copper oxide nanoparticles that daignosed and characterized using AFM technique. This research was implemented at plant tissue culture labrotary  of College of biotechnology - Al Nahrain University, during the period of 2021 and 2023. The experiment designed factorial within CRD using three factors and ten replicates (3X3). Sodium hypochlorite concentration (S1, S2, S3, S4) (0.0, 1, 2, 3%) represented the first factor, treatment duartion time (T1, T2, T3) (5, 10, 15min) represented the  second factor and copper oxide nanoparticles concentrations (C1, C2, C3, C4) (0.0, 25, 50, 75mg/ml) represented the  third factor. Results showed that the full reduction in the contamination rate of the selected E. purpurea explant recorded in 3% sodium hypochlorite at 10 and 15min. The results also showed that there were a significant increase in the shoots numbers in 50mg/ml CuNPs that recording the highest shoots numbers, the shoot length increased significantly within the 25mg/ml recording 13.5cm then decreased in 50 and 75 mg/ml and the seedlings dry weight increased significantly up to 50mg/ml CuNPs that recording the highest seddlings dry weight, then the seedlings dry weight also decreased significantly in 75mg/ml  CuNPs. Also, all the analyzed flavonoids compounds using HPLC device as Echinolone,  Humulene, Coumarin, Myricetin, Heperidin and Naringin concentrations were significantly increased in 50 and 75 mg/L-1 Cu ONPs, except the  Humulene and Coumarin compound that significantly decreased in 75 mg/L-1 Cu ONPs in comparsion to the control.

EFFECT OF DIFFERENT LEVELS OF SALT AND DROUGHT STRESSES ON GENE EXPRESSION OF TWO TOLERANCE-DIFFERENT TOMATO CULTIVARS IN VITRO

A lab experiment was conducted at the Plant Tissue Culture Lab / College of Agricultural Engineering Sciences / University of Baghdad. This experiment was aimed to investigate gene expression index in tomato (Solanum lycopersicum L.) after preparation of salt and simulated drought stresses. Two tomato cultivars were selected which claimed to exhibit different levels of tolerance toward abiotic stresses designated as salt-tolerant Yassamine (Y) and salt-sensitive GS12 (G) to assess the test. Seven day-old seedlings from both cultivars were grown in MS media supplemented with four concentrations of NaCl at 0, 50, 100 and 150 mM and four concentrations of PEG at 0, 10, 20, and 30% for 48 hours. The results were showed that Y cultivar exhibited more proline secretion and chlorophyll content when compared with G. In addition, Y cultivar showed less ion leakage and less affected by elevated abiotic stresses in term of seedling weight variation when compared to G counterparts. The SDS-PAGE gel analysis showed that Y cultivar showed more band intensity when compared with G suggested more corresponding gene expression of tolerant protein against abiotic stresses.   

Rapid Multiplication of Geographical Indication (GI) Tagged Mysore Mallige (Jasminum azoricum L.) Using Single Node through In vitro Culture

Aims: The present study was undertaken to rapid multiplication of (GI) tagged Mysore Mallige (Jasminum azoricum L.) using single node through in vitro culture. Study Design: The present study follow Completely Randomized Design (CRD). Place and Duration of Study: The study was conducted at the Plant Tissue Culture Laboratory, Department of Horticulture, University of Agricultural Sciences, Gandhi Krishi Vignana Kendra, Bengaluru, from 2020 to 21. Methodology: Single node cutting from the young shoots of field growing plants were used as explants to conduct the experiment. The explants were sterilized and placed on MS medium supplemented with different concentrations and combinations of growth regulators, namely BAP and Kinetin. Results: Among the different combinations of growth regulators, the combination of BAP 1.5 mg L-1   and Kin 1.5 mg L-1  produced maximum number of shoots from single node. Very low intensity of callus formation was observed from the cut ends of single node explants that were cultured on half strength MS medium consisting of 1.5 mg L-1 BAP + 0.0 mg L-1 Kin and 1.5 mg L-1 BAP + 1.0 mg L-1 Kin. Conclusion: The use of growth regulators such as BAP and KIN is reliable for shoot regeneration even when the field explants are used.

Effect of biosynthesised silver nanoparticles as sterilant on physiological and biochemical characteristics in micropropagation of Musa sapientum L.

Green synthesis of silver nanoparticles (AgNPs) using fruit peel extract has gained considerable interest, as it is an eco-friendly and cost-effective method. However, studies on the use of biosynthesised AgNPs to sterilise plant tissue culture medium as an alternative to autoclaving are limited. Thus, this study presented a biogenic method for synthesising AgNPs using mangosteen peel extract. The biosynthesised AgNPs were characterised by different spectroscopic and microscopic methods, including UV-visible spectroscopy (UV-vis), Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy, and energy dispersive x-ray spectroscopy. The results showed that the phytochemical constituents in the mangosteen peel extract (MPE) helped to reduce Ag+ from AgNO3 to metallic silver (Ag0) and stabilise the particles. The formation of biogenic AgNPs was monitored by UV-vis demonstrating a characteristic peak at 425 nm. The AgNPs were spherical and crystalline. The size distribution of the biogenic AgNPs was 5–47 nm with an average diameter of 23.1 ± 6.8 nm. To evaluate the potential of the AgNPs for use as an alternative method to sterilise the culture medium, the antimicrobial activity of the biosynthesised AgNPs (0.1, 1, 10, 100, and 1000 mg l−1) was tested in the banana culture medium. The most feasible concentration of AgNPs to decontaminate the culture medium was 100 mg l−1. Moreover, the results demonstrated that adding 100 mg l−1 AgNPs to the culture medium promoted the growth of the plantlets without any toxic effects. Thus, biogenic AgNPs are a potential biocide to sterilise in vitro banana culture medium.

Floriculture and Transgenic

“Genetic engineering has revolutionized floriculture by enabling the modification of plant species and the creation of new flower color varieties (Chandler, Stephen et al, 2010). Despite the global cultivation of transgenic crops, floriculture has been slow to adopt transgenic breeding. "Floriculture, with its cut flower market as a significant component, is on track to achieve a market size of $43.8 billion by 2027, according to Markets and Markets. This industry plays a crucial role in uplifting rural economies through international trade. For instance, floriculture products from Africa find their way to markets in the U.S. and Europe. Similarly, Asian nations such as Japan, China, and India are strengthening their financial positions through the import and export of floriculture commodities (Tanaka, Yoshizu et al., 2009). One of the notable advancements in floriculture has been the creation of new flower color varieties by manipulating pigment metabolic pathways in plants. However, there are challenges. Some flowering plants, despite their high market value, do not realize their full economic potential due to issues like prolonged flowering seasons and diseases." These challenges can be addressed through the production of transgenic plants using genetic engineering and plant tissue culture techniques. The study aims to explore the potential of genetic engineering associated with plant tissue culture techniques in enhancing floriculture, particularly in developing new flower color varieties and improving the production of high-value flowering plants, thereby highlighting the economic impact of floriculture globally.

Improving transformation and regeneration efficiency in medicinal plants: Insights from other recalcitrant species.

Medicinal plants are integral to traditional medicine systems world-wide, being pivotal for human health. Harvesting plant material from natural environments, however, has led to species scarcity, prompting action to develop cultivation solutions that also aid conservation efforts. Biotechnological tools, specifically plant tissue culture and genetic transformation, offer solutions for sustainable, large-scale production and enhanced yield of valuable biomolecules. While these techniques are instrumental to the development of the medicinal plant industry, the challenge of inherent regeneration recalcitrance in some species to in vitro cultivation hampers these efforts. This review examines the strategies for overcoming recalcitrance in medicinal plants using a holistic approach, emphasising the meticulous choice of explants, e.g. embryonic/meristematic tissues; plant growth regulators, e.g. synthetic cytokinins; and use of novel regeneration-enabling methods to deliver morphogenic genes e.g. GRF/GIF chimeras and nanoparticles, which have been shown to contribute to overcoming recalcitrance barriers in agriculture crops. Furthermore, it highlights the benefit of cost-effective genomic technologies that enable precise genome editing and the value of integrating data-driven models to address genotype-specific challenges in medicinal plant research. These advances mark a progressive step towards a future where medicinal plant cultivation is not only more efficient and predictable but also inherently sustainable, ensuring the continued availability and exploitation of these important plants for current and future generations.

Studies on In vitro Surface Sterilisation and Antioxidants on Pomegranate (Punica granatum L.) cv. Bhagwa

Pomegranate, regarded as the “Fruit of Paradise”, is one of the important fruit crops of tropical and subtropical regions. Pomegranate fruits are delicious and possess significant nutritional and medicinal benefits. Due to the increase in demand, the proliferation of pomegranate through tissue culture is essential to get high-quality planting material. However, microbial contamination in plant tissue culture is one of the bottlenecks for establishing aseptic cultures. Although multiple explant sterilisation methods have been developed for pomegranate, explant sterilisation methods can indeed vary from region to region due to the local environment and the mother plant. In the present study, 1-2 drops of tween 20 (20 min) + 500 mg/L carbendazim (30 min) + 500 mg/L streptomycin sulphate (10 min) + 100 mg/L citric acid (30 min) + 100 mg/L tebuconazole (folicur) (30 min) + 0.1% HgCl2 (1 min) + dipping explant after cutting the edges in sterile water (30 min) + dipping in 500 mg/L PVP (5 min) was found to be optimum in the prevention of microbial contamination with minimal cell death. Nodal segments-initiated callus at 54 days after culture, showing a callus induction percentage of 55.55% and a calli weight of 80 mg/explant.

A review on plant tissue culture: A technique for propagation and conservation of Butea monosperma (Lam.) Taub. var. lutea (Witt.)

A review on plant tissue culture: A technique for propagation and conservation of Butea monosperma (Lam.) Taub. var. lutea (Witt.)

Unfolding phenolics biosynthetic plasticity of Artemisia alba Turra through plant tissue culture techniques

Unfolding phenolics biosynthetic plasticity of Artemisia alba Turra through plant tissue culture techniques

Outbreak of Septoria leaf spot caused by Sphaerulina musiva on Populus × euramericana in China.

In June 2023, severe leaf spots were noted in Populus × euramericana cv 'Nanlin95' plantations located in the Nanjing Baguazhou Wetland Park (32°09'16.97″N, 118°48'16.74″E) of Jiangsu Province and Populus × canadensis cv 'Sacrau 79' and Populus × canadensis cv 'Guariento' in the Liyuan Village in Nanyang City (32°53'43.70″N, 112°17'29.12″E) of Henan Province, respectively. The disease incidence in both locations could reach 97.9% (556 out of 568 trees) and 98.9% (2409 out of 2436 trees), respectively. The initial symptoms appear as numerous small and circular spots (1.59 to 3.18 mm in diameter) with gray or tan centers and dark-brown margins on the leaves. As the spots age, they sometimes enlarge, often coalesce, and may extend down the petioles. Diseased leaves and petioles were both surface sterilized with 75% ethanol for 30 seconds. With the aid of a hand lens, pycnidia (brown to black, spherical in profile, 90 to 250 µm diam) were easily picked out in the center of the spots and subsequently transferred into 1 mL sterilized water for preparing the spore suspension plated on KV8 medium amended with 100 mg/liter streptomycin sulfate and 50 mg/liter chloramphenicol. After 12 days of incubation, 86 single-spore isolates were obtained and identified as typical Septoria-like fungi according to morphological features, including slow-growing, gray or black colonies with pink mucilaginous matrix and hyaline, straight or curved conidia (size = 25 to 59 × 3.5 to 4 μm; septa = 1 to 6). Species identification was further validated by PCR amplification and sequencing of the internal transcribed spacer (ITS) region with ITS1/ITS4 primer pairs. Multiple sequence alignments with ClustalW revealed that the obtained ITS sequences of 86 isolates were 100% identical to each other. A BLAST search in GenBank indicated that the selfsame sequences of two representative isolates (isolate BGZ11 of Jiangsu Province, accession no. OR660379; isolate KZB22 of Henan Province, accession no. OR711499) shared 99.8% identity (494 of 495 bp) and 100% identity (504 of 504 bp) with related sequences of Sphaerulina musiva (Peck) Quaedvlieg, Verkley, and Crous (syn. = Septoria musiva Peck) in GenBank (MN275187; KF251619), respectively. Furthermore, we used a S. musiva-specific PCR assay (Abraham et al. 2018) on symptomatic leaf samples collected from the plantation. Each sample consisted of 20 cut-out leaf spots per leaf. Eight of the 10 samples were positive for S. musiva DNA. To confirm pathogenicity, six sterile tissue culture of poplar plants (Populus trichocarpa and Populus × euramericana cv 'Nanlin895') were respectively transplanted into pots and grown in a greenhouse for a week and for a month with an 18-h photoperiod augmented with sodium lamps and a 20°C (day)/16°C (night) temperature regime. Inoculations were conducted by spraying the plants with conidia suspension (106 conidia/mL) (LeBoldus et al. 2010). Control plants were sprayed with distilled water. Leaf spots were developed on the inoculated P. trichocarpa leaves at one week and P. × euramericana cv 'Nanlin895' leaves at 10 days after inoculation while no symptoms were observed on the control plants. The fungus S. musiva was successfully reisolated from all symptomatic leaves fulfilling Koch's postulates. Sphaerulina musiva only causes an endemic leaf spot disease on its natural North American host Populus. deltoides (Feau et al. 2010; Ostry 1987). However, on susceptible Populus species (e.g., P. balsamifera, P. trichocarpa, P. maximowiczii) and hybrids, S. musiva causes not only leaf spots but also severely damaging stem and branch cankers (Jeger et al. 2018; LeBoldus et al. 2009; Sondreli et al. 2020). To our knowledge, this is the first report of S. musiva causing leaf spots on poplar in China. Large-scale timber imports (e.g., cut branches, isolated bark, wood with and without bark) potentially lead to anthropogenic-facilitated transport of this pathogen. This outbreak of Septoria leaf spot underscores the potential threat of this pathogen to P. × euramericana in China, where it is widely planted as a keystone forestry species.

Bulbil initiation: a comprehensive review on resources, development, and utilisation, with emphasis on molecular mechanisms, advanced technologies, and future prospects.

Bulbil is an important asexual reproductive structure of bulbil plants. It mainly grows in leaf axils, leaf forks, tubers and the upper and near ground ends of flower stems of plants. They play a significant role in the reproduction of numerous herbaceous plant species by serving as agents of plant propagation, energy reserves, and survival mechanisms in adverse environmental conditions. Despite extensive research on bulbil-plants regarding their resources, development mechanisms, and utilisation, a comprehensive review of bulbil is lacking, hindering progress in exploiting bulbil resources. This paper provides a systematic overview of bulbil research, including bulbil-plant resources, identification of development stages and maturity of bulbils, cellular and molecular mechanisms of bulbil development, factors influencing bulbil development, gene research related to bulbil development, multi-bulbil phenomenon and its significance, medicinal value of bulbils, breeding value of bulbils, and the application of plant tissue culture technology in bulbil production. The application value of the Temporary Immersion Bioreactor System (TIBS) and Terahertz (THz) in bulbil breeding is also discussed, offering a comprehensive blueprint for further bulbil resource development. Additionally, additive, seven areas that require attention are proposed: (1) Utilization of modern network technologies, such as plant recognition apps or websites, to collect and identify bulbous plant resources efficiently and extensively; (2) Further research on cell and tissue structures that influence bulb cell development; (3) Investigation of the network regulatory relationship between genes, proteins, metabolites, and epigenetics in bulbil development; (4) Exploration of the potential utilization value of multiple sprouts, including medicinal, ecological, and horticultural applications; (5) Innovation and optimization of the plant tissue culture system for bulbils; (6) Comprehensive application research of TIBS for large-scale expansion of bulbil production; (7) To find out the common share genetics between bulbils and flowers.

In Vitro Microrhizome Production, Genetic Homogeneity Assessment, and Field Performance Evaluation in Ginger

In vitro-induced microrhizomes are promising for producing disease-free planting materials in ginger (Zingiber officinale Rosc.), spice and medicinal crops threatened by several soil-borne diseases. The study examined microrhizome induction, genetic homogeneity, and field performance in ginger. The condition combination of 3.0 mg·L−1 6-benzylaminopurine (BAP), 100 g·L−1 sucrose, and a 12-h photoperiod (the optimal conditions) produced the largest number of microrhizomes among all treatments but resulted in a lower average fresh weight during the 60-day culture period. Larger microrhizomes exhibited greater tolerance to water loss and a higher percentage of sprouting. Therefore, additional efforts were made to increase the size of the microrhizomes. Under the optimal conditions, the fresh weight increased significantly to 280.3 mg and 403.4 mg after 30 days of additional culture and in vitro culture of small-sized microrhizomes, respectively. Flow cytometry analysis and SSR characterization confirmed the genetic homogeneity of the regenerated plants with microrhizomes (MR) and those obtained by directly sowing sprouted microrhizomes into the substrate without acclimatization (FMR). At harvest, the MR had the most robust growth, a significantly higher fresh rhizome weight (206.1 g per plant) than the FMR (121.8 g per plant) and conventional tissue-cultured plants (TC), and similar rhizome finger size (11.5 g and 10.2 cm2) to the FMR. These findings suggest that both the MR and the FMR have advantages over the TC in producing seedling rhizomes of ginger in the first growing season. The established approach may be useful for large-scale production of disease-free ginger rhizomes.

The role of silver nanoparticles biosynthesized from Citrus aurantium Leaves in some Vegetative and physiological characteristics of fenugreek plant (Trigonella foenum- graecum L.)

The research was crried out in the plant tissue culture laboratory and the green house of Department of plant Biotechnology in College of Biotechnology/AL-Nahrain University. The aim of it, is the Green-synthesis of silver nanoparticles by using an aqueous extract of Citrus aurantium leaves and characterizied the silver nanoparticles, using visible method depend on colour changing of the solution(mixture of aqueous extract of C. aurantium leaves and 1mMol of AgNO3 under 60C ̊), UV-Visible spectroscopy method and Atomic Force Microscopy (AFM), then study the effects of foliar spray of of AgNPs on some vegetative and physiological characteristics of Fenugreek Plant (Trigonella foenum- graecum L.), such as fresh and dry weight, length of shoot, carbohydrates, proteins and proline. The result showed the positive effect of using AgNPs on these characteristics.

Light as an elicitor for enhanced production of secondary metabolites in plant cell, tissue, and organ cultures

Light as an elicitor for enhanced production of secondary metabolites in plant cell, tissue, and organ cultures

Plant regeneration capacity in seeds of three species of Miconia (Melastomataceae) may be related to endogenous polyamine profiles.

In plant tissue culture, differences in endogenous levels of species-specific plant growth regulators (PGRs) may explain differences in regenerative capacity. In the case of polyamines (PAs), their dynamics and distribution may vary between species, genotypes, tissues, and developmental pathways, such as sexual reproduction and apomixis. In this study, for the first time, we aimed to assess the impact of varying endogenous PAs levels in seeds from distinct reproductive modes in Miconia spp. (Melastomataceae), on their in vitro regenerative capacity. We quantified the free PAs endogenous content in seeds of Miconia australis (obligate apomictic), Miconia hyemalis (facultative apomictic), and Miconia sellowiana (sexual) and evaluated their in vitro regenerative potential in WPM culture medium supplemented with a combination of 2,4-dichlorophenoxyacetic acid (2,4-D) and 6-benzylaminopurine (BAP). The morphogenic responses were characterized by light microscopy and scanning electron microscopy and discussed regarding the endogenous PAs profiles found. Seeds of M. sellowiana presented approximately eight times more putrescine than M. australis, which was associated with a higher percentage of regenerated calluses (76.67%) than M. australis (5.56%). On the other hand, spermine levels were significantly higher in M. australis. Spermine is indicated as an inhibitor of auxin-carrying gene expression, which may have contributed to its lower regenerative capacity under the tested conditions. These findings provide important insights into in vitro morphogenesis mechanisms in Miconia and highlight the significance of endogenous PA levels in plant regeneration. These discoveries can potentially optimize future regeneration protocols in Miconia, a plant group still underexplored in this area.

Critical Appraisal of Nothapodytes nimmoniana (J. Graham) Mabb. Extraction Methods, Pharmacological Activities, and Future Prospects

Nothapodytes nimmoniana (J. Graham) Mabb., commonly known as Narkya, holds immense potential as a medicinal plant, exhibiting a wide array of pharmacological activities. This review provides a comprehensive overview of the methods used for extracting bioactive compounds from different plant parts, along with an exploration of their diverse pharmacological activities. The plant’s significance stems from its high content of camptothecin (CPT), a potent anti-cancer alkaloid. We delve into the plant’s anti-microbial, antioxidant, anti-tumor, anti-helminthic, anti-malarial, and anti-inflammatory properties. Additionally, we highlight the challenges faced by N. nimmoniana (J. Graham) Mabb., due to overexploitation and its endangered status. To address these concerns, the review underscores the importance of sustainable conservation strategies and the implementation of advanced techniques like plant tissue culture and endophyte production for increased CPT production. This holistic analysis not only sheds light on the plant’s multifaceted benefits but also underscores the need for responsible utilization and conservation efforts.