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Date palm(Phoenix dactylifera L.) holds substantial agricultural, nutritional, and economic significance, particularly in arid and semi-arid regions. Traditional propagation methods, such as offshoot and seed propagation, face limitations including slow growth rates, limited availability of offshoots, and genetic instability, making the adoption of in vitro culture techniques essential for the mass propagation and genetic improvement of Date palm. This comprehensive review delves into the intricacies of in vitro culture protocols for Date palm, focusing on the development of multiple shoot, root, and organ cultures. The review meticulously examines the critical factors influencing each stage of in vitro propagation, including the selection of explants, optimization of culture media, and control of environmental conditions. The efficacy of different plant growth regulators (PGRs), such as cytokinins and auxins, in promoting shoot proliferation, root induction, and organogenesis is compared and analyzed, highlighting the optimal concentrations and combinations for successful tissue culture outcomes. For multiple shoot induction, the review discusses the use of shoot tips, axillary buds, and immature inflorescences, with media formulations like MS, B5, and WPM supplemented with specific PGRs such as BAP and kinetin. The process of root induction is examined, emphasizing the role of auxins like IBA and NAA in developing robust root systems and the influence of environmental factors like light and temperature. Organ culture techniques, particularly embryogenic callus induction and somatic embryogenesis, are explored, detailing the use of high auxin concentrations for callus formation and the transition to media with balanced PGRs for embryo maturation. Additionally, the review addresses the challenges of somaclonal variation and genetic stability in tissue culture, proposing strategies for monitoring and mitigating these issues through genetic and epigenetic analyses. The potential of integrating advanced biotechnological tools, such as CRISPR/Cas9, for precise genetic modifications is discussed, alongside the need for improved acclimatization protocols to enhance the survival rates of in vitro propagated plantlets. Future research directions are identified, focusing on minimizing somaclonal variation, optimizing acclimatization, exploring diverse explant sources, and scaling up production through automated culture systems. By synthesizing the latest research findings and offering detailed comparisons of various in vitro protocols, this review aims to provide a valuable resource for researchers and practitioners seeking to enhance the efficiency and success of Date palm micropropagation, ultimately contributing to the sustainable cultivation and genetic improvement of this vital crop. [ABSTRACT FROM AUTHOR]

Introduction: Developing somatic embryogenesis is one of the main steps in successful in vitro propagation and gene transformation in the carrot. However, somatic embryogenesis is influenced by different intrinsic (genetics, genotype, and explant) and extrinsic (e.g., plant growth regulators (PGRs), medium composition, and gelling agent) factors which cause challenges in developing the somatic embryogenesis protocol. Therefore, optimizing somatic embryogenesis is a tedious, time-consuming, and costly process. Novel data mining approaches through a hybrid of artificial neural networks (ANNs) and optimization algorithms can facilitate modeling and optimizing in vitro culture processes and thereby reduce large experimental treatments and combinations. Carrot is a model plant in genetic engineering works and recombinant drugs, and therefore it is an important plant in research works. Also, in this research, for the first time, embryogenesis in carrot (Daucus carota L.) using Genetic algorithm (GA) and data mining technology has been reviewed and analyzed. Materials and methods: In the current study, data mining approach through multilayer perceptron (MLP) and radial basis function (RBF) as two well-known ANNs were employed to model and predict embryogenic callus production in carrot based on eight input variables including carrot cultivars, agar, magnesium sulfate (MgSO4), calcium dichloride (CaCl2), manganese (II) sulfate (MnSO4), 2,4-dichlorophenoxyacetic acid (2,4-D), 6-benzylaminopurine (BAP), and kinetin (KIN). To confirm the reliability and accuracy of the developed model, the result obtained from RBF-GA model were tested in the laboratory. Results: The results showed that RBF had better prediction efficiency than MLP. Then, the developed model was linked to a genetic algorithm (GA) to optimize the system. To confirm the reliability and accuracy of the developed model, the result of RBF-GA was experimentally tested in the lab as a validation experiment. The result showed that there was no significant difference between the predicted optimized result and the experimental result. Conclutions: Generally, the results of this study suggest that data mining through RBF-GA can be considered as a robust approach, besides experimental methods, to model and optimize in vitro culture systems. According to the RBF-GA result, the highest somatic embryogenesis rate (62.5%) can be obtained from Nantes improved cultivar cultured on medium containing 195.23 mg/l MgSO4, 330.07 mg/l CaCl2, 18.3 mg/l MnSO4, 0.46 mg/l 2,4- D, 0.03 mg/l BAP, and 0.88 mg/l KIN. These results were also confirmed in the laboratory [ABSTRACT FROM AUTHOR]

Introduction: Acer truncatum Bunge, belonging to the Acer genus in the Aceraceae family, is a commonly planted afforestation species across China, Japan, Korea, Europe, and North America. Renowned for its vibrant fall colors, it holds significant ecological and ornamental value. Methods: In this study, Acer truncatum 'Lihong' was used as the research object. Starting from the callus induction of explants, the embryogenic callus of Acer truncatum 'Lihong' was obtained by systematically optimizing the medium and culture conditions. Then, the candidate gene AtrGST894 screened by transcriptome sequencing was transformed into embryogenic callus by Agrobacterium-mediated transformation. The genetic transformation system of Acer truncatum 'Lihong' embryogenic callus was initially established by continuously adjusting the conditions of Agrobacterium tumefaciens infection receptor materials, thus laying amaterial foundation for the study of themolecular regulation mechanismof Acer truncatum'Lihong' leaf color, and also preparing for the later molecular improvement breeding of Acer truncatum. Therefore, this study has important theoretical and practical significance. Results: The results showed that the best medium for callus induction of Acer truncatum was 1/2MS+2 mg/L 2,4-D+0.3 mg/L 6-BA+0.5 mg/L NAA; The embryogenic callus induction medium of Acer truncatum was 1/2MS+3.0mg/L 6-BA+2.0mg/L TDZ+0.5mg/L IBA+0.1mg/L GA3; The proliferation medium of embryogenic callus of Acer truncatum was WPM+1.0mg/L TDZ+0.5mg/L IBA +0.1mg/L GA3+3mg/L 6-BA+1.0mg/L KT; The infection experiment of Agrobacterium tumefaciens on the embryogenic callus of Acer truncatum showed that the best antibacterial medium was WPM+30g/L sucrose+8g/L agar+0.5g/L acid-hydrolyzed casein+0.2mg/L KT+1.0 mg/L TDZ+0.5 mg/L IBA+0.1 mg/L GA3 +200mmol/L carboxybenzyl+200mg/L cephalosporin, and then WPM+30g/L sucrose+8g/L agar+0.5g/L acid-hydrolyzed casein+0.2mg/L KT+1.0 mg/L TDZ +0.5 mg/L IBA+0.1 mg/L GA3+300mmol/L carboxybenzyl+200mg/L cephalosporin+25mg/L hygromycin. Screening medium screening, The obtained embryogenic callus browning rate, pollution rate andmortality rate were the lowest, and maintained vigorous growth. Discussion: The embryogenic callus was used as the infection material to verify that we successfully transferred the target gene into the embryogenic callus, which means that the genetic transformation system of Acer truncatum embryogenic callus was partially completed, and the infection process could be effectively inhibited. Although there was partial browning, it could continue to proliferate. Therefore, in future experiments, the focus is still to continue to verify the optimal conditions for optimizing the genetic transformation of Acer truncatum embryogenic callus and to solve the problems of difficulty in embryonic callus germination. [ABSTRACT FROM AUTHOR]

ABSTRACT The isolated microspores can be reprogrammed towards embryogenesis via stress treatment during in vitro culture, and produce (doubled) haploid plants as a breeding source of new genetic variability. However, the mechanism underlying the cell fate transition from gametogenesis to embryogenesis remains largely unknown. Here, we report that autophagy plays a key role in cell fate transition for microspore embryogenesis (referred to as androgenesis) in Nicotiana tabacum. Immunofluorescence and transmission electronic microscopy detection unveiled that autophagy was triggered in microspores following exposure to inductive stress, and a transient wave of the numerous autophagy‐related genes (ATGs) expression occurred before the initiation of microspore embryogenesis. Suppression or promotion of the original autophagy levels could inhibit microspore embryogenesis, indicating that stress‐induced autophagic homeostasis is essential for cell fate transition. Furthermore, quantitative proteomics analysis revealed that autophagy might be involved in lignin biosynthesis and chromatin decondensation for promoting reprogramming for androgenesis initiation. Altogether, we reveal an essential role of autophagy in the microspore cell fate transition and androgenesis initiation, providing novel insight for understanding this critical developmental process. [ABSTRACT FROM AUTHOR]

This is the first initiative study to provide quantified levels of four endogenous phytohormones during the induction, regeneration, maturation and germination stages of somatic embryogenesis (SE) in banana, using immature male bud explants, in the popular commercial triploid cultivar Grand Naine (AAA). Phytohormones are known to play a major role in the regulation of SE and most protocols have been developed for various cultivars of banana following empirical approaches. Although, several reports are available with regard to the impact of growth regulators exogenously supplemented to the media, the vital role of endogenous growth hormones in various developmental stages of SE remain unclear in banana. Reverse Phase High Performance Liquid Chromatography (RP-HPLC) was used to analyze endogenous status of indole acetic acid (IAA), zeatin, gibberellic acid (GA) and abscisic acid (ABA). Results from this study revealed that endogenous IAA and GA along with exogenous auxin play a major role in the induction of embryogenic competence of male bud explants. The levels of endogenous IAA and zeatin were found to be higher in embryogenic calli than non-embryogenic calli, although three different types of exogenous auxins were supplemented in callogenesis medium, but not cytokinin. Higher level of ABA and GA was observed in early and late developmental stages of somatic embryo, respectively. GA also played a predominant role in germination of somatic embryos. These findings will be applied for improvement of SE protocol in recalcitrant banana cultivars by suitably altering or supplementing exogenous growth hormones. [ABSTRACT FROM AUTHOR]

SUMMARY The lenticel is a channel‐like structure that facilitates oxygen, carbon dioxide, and water vapor exchange on secondary growth tissue, such as a tree stem. Although the structure of lenticel has been described, there is limited understanding regarding the impact of this secondary structure on secondary growth as well as the cellular and metabolic processes underlying its formation. The study reveals the essential role of the lenticel in the process of tree secondary growth and the cellular and metabolic processes that take place during its formation. Under the stomata, lenticel development occurs when cells divide and differentiate into a structure of disconnected cells with air spaces between them. During lenticel formation, specific metabolic pathways and wax biosynthesis are activated. The SERK (somatic embryogenesis receptor kinase) gene controls lenticel density, and serk1serk3serk5 triple mutants enhance lenticel initiation. The findings shed light on the cellular and metabolic processes involved in lenticel formation, laying the groundwork for further mechanistic elucidation of their development, function, and genetic regulation in trees. [ABSTRACT FROM AUTHOR]

Aseptic seedlings of different ages derived from surface-sterilized mature seeds were applied as an explant source. Various explants such as 7- and 21-day-old hypocotyl fragments, 42-day-old nodal stem segments, and transverse nodal segments of stem, as well as leaf petioles, were cultured on the agar-solidified Murashige and Skoog (MS) basal medium supplemented with 0.1 mg/L IAA, 5 mg/L AgNO3 and different types and concentrations of cytokinin (1 mg/L zeatin, 0.25 mg/L thidiazuron (TDZ), and 5 mg/L 6-benzylaminopurine (6-BAP)). Consequently, it was found that 7- and 21-day-old hypocotyl fragments, as well as nodal stem segments obtained from adult aseptic seedlings, are characterized by a high explant viability and callus formation capacity with a frequency of 79.7–100%. However, the success of in vitro somatic shoot organogenesis was significantly determined not only by the culture medium composition and explant type but also depending on its age, as well as on the size and explant preparation in cases of hypocotyl and age-matched nodal stem fragments, respectively. Multiple somatic shoot organogenesis (5.7 regenerants per explant) with a frequency of 67.5% was achieved during 3 subcultures of juvenile hypocotyl-derived callus tissue on MS culture medium containing 0.25 mg/L TDZ as cytokinin source. Castor bean regenerants were excised from the callus and successfully rooted on ½ MS basal medium without exogenous auxin (81%). In vitro plantlets with well-developed roots were adapted to ex vitro conditions with a frequency of 90%. [ABSTRACT FROM AUTHOR]

The embryogenic transition of plant somatic cells to produce somatic embryos requires extensive reprogramming of the cell transcriptome. The prominent role of transcription factors (TFs) and miRNAs in controlling somatic embryogenesis (SE) induction in plants was documented. The profiling of MIRNA expression in the embryogenic culture of Arabidopsis implied the contribution of the miR156 and miR169 to the embryogenic induction. In the present study, the function of miR156 and miR169 and the candidate targets, SPL and NF-YA genes, were investigated in Arabidopsis SE. The results showed that misexpression of MIRNA156 and candidate SPL target genes (SPL2, 3, 4, 5, 9, 10, 11, 13, 15) negatively affected the embryogenic potential of transgenic explants, suggesting that specific fine-tuning of the miR156 and target genes expression levels seems essential for efficient SE induction. The results revealed that SPL11 under the control of miR156 might contribute to SE induction by regulating the master regulators of SE, the LEC (LEAFY COTYLEDON) genes (LEC1, LEC2, FUS3). Moreover, the role of miR169 and its candidate NF-YA targets in SE induction was demonstrated. The results showed that several miR169 targets, including NF-YA1, 3, 5, 8, and 10, positively regulated SE. We found, that miR169 via NF-YA5 seems to modulate the expression of a master SE regulator LEC1/NF-YA and other auxin-related genes: YUCCA (YUC4, 10) and PIN1 in SE induction. The study provided new insights into miR156-SPL and miR169-NF-YA functions in the auxin-related and LEC-controlled regulatory network of SE. [ABSTRACT FROM AUTHOR]

In recent years, proteomics has become a powerful tool in vitro plant tissue culture research. In Miconia , the most diverse flowering plant genus in the Neotropics, these tools together were unexplored. The group is replete with cases of apomixis (asexual seed formation). Some studies indicate that apomixis may have similarities with somatic embryogenesis (SE). However, there is no investigation into whether explants from apomictic species can affect the accumulation of SE-related proteins in vitro morphogenesis processes, such as callogenesis. This study identifies differentially accumulated proteins related to SE in the callogenesis of three Miconia species with different reproductive systems and whether this can affect their embryogenic capacity. For this, we employed the shotgun comparative proteomics approach in a specific phase of callus proliferation of Miconia australis (obligate apomictic), Miconia hyemalis (facultative apomictic), and Miconia sellowiana (sexual). Comparative proteomic analysis revealed that 190 SE-related proteins were differentially accumulated and distributed among the three experimental comparisons. The calluses of apomictic species showed the highest number of up-accumulated proteins associated with SE. Histological examination of the calluses after 45 days of induction revealed the permanence of cells with meristematic characteristics in the apomictic species, however, in M. sellowiana there was greater cellular vacuolization. These results indicate that calluses of Miconia spp. originated from apomictic species may be better able to acquire embryogenic competence in vitro culture. This study is the first to explore and demonstrate the potential advantages of using proteomics to understand the molecular basis of in vitro morphogenesis in apomictic and sexual species of Miconia , highlighting new perspectives for future research in plant tissue culture. [Display omitted] • Proteomics shed light into the mechanisms underlying in vitro morphogenesis in miconia. • Calluses from apomictic miconia up-accumulated proteins related to somatic embryogenesis. • The cu/zn SOD was up-accumulated in the calluses of obligate apomictic M. australis. • Apomictic species showed a higher prevalence of callus cells with meristematic characteristics. [ABSTRACT FROM AUTHOR]

• Paphiopedilum spp. is known as lady slipper orchid. • Embryogenesis in Paphiopedilum spp. can be induced with plant growth regulator. • Development of somatic embryos in Paphiopedilum spp. is the same as zygotic embryos. • The homologous embryo gene RKD4 is present and functional in Paphiopedilum spp. Paphiopedilum spp. is one of the terrestrial orchids that is interesting as an ornamental plant. This orchid flower has a distinctive characteristic, namely its labellum resembles a sac, so it is sought after by ornamental flower collectors because of its uniqueness. This orchid is included in the Appendix I group according to CITES, namely a critical species that is threatened with extinction, so it needs to be conserved both in situ and ex situ. Ex situ conservation can be done by propagating orchids using in vitro culture techniques. The objective of this research is to carry out mass propagation of 3 species of Paphiopedilum spp orchids: P. supardii, P. primulinum, P. glaucophyllum through somatic embryogenesis and to characterize the existence of embryo gene RKD4 homolog in Paphiopedilum orchids. The method is to culture the nodes slices in dark conditions for 2 weeks, and then changed to photoperiod mode 16:8 hours (dark:light) on ½ MS media plus a combination of 2,4-D or NAA with TDZ. The somatic embryo were analyzed anatomically. This method is an improvement over previously reported methods for Paphiopedilum spp. due to its efficiency and reproducibility for conservation. We concluded that ½ MS media with a combination of NAA or 2,4D with TDZ were able to induce somatic embryogenesis. The result show that 3 mg L−1 NAA was the best PGRs for PLBs induction in P. supardii (50 %), 1 mg L−1 2,4-D + 0.5 mg L−1 TDZ was the best PGRs for callus embryogenic induction in P. primulinum (20 %), and 1 mg L−1 NAA was the best PGRs for PLBs induction in P. glaucophyllum (33 %). [ABSTRACT FROM AUTHOR]

Nano-gardening has revolutionized agriculture by leveraging nanotechnology for enhanced plant growth and sustainability. Among different types of nanoparticles, metal nanoparticles (MNPs) are recognized as potential candidates for use in diverse agricultural products like fertilizers, growth enhancers, and pesticides per se. Additionally, there is an increasing interest in regulating plant regeneration with the application of MNPs. Understanding the influence of these nano-scale particles on different aspects of plant developmental biology and their underlying mechanism is quite indispensable. In this review, the effect of different MNPs like silver nanoparticles (AgNPs), gold nanoparticles (AuNPs), Titanium oxide nanoparticles (TiO2NP), Iron oxide nanoparticles (FeNP), Zinc Oxide Nanoparticles (ZnONP), and Copper nanoparticles (CuNP) was considered. Among all the applications of nanoparticles on plant systems, the studies on improvements in shoots and root multiplication, induction of callus cultures, and establishment of somatic embryogenesis have gained the utmost importance. The advancement in plant tissue culture techniques has enormous importance in plant micropropagation, disease elimination, and increase in plant secondary metabolite production. The present review focused on the role of different MNPs in controlling the plant regeneration processes and their associated mechanisms of action. The study also tried to compile the overall plausible mode of action of MNPs in upgrading the plant regeneration process which involves the triggering of different signalling cascades in plant cells. [ABSTRACT FROM AUTHOR]

As one of the most important members of the palm family, coconut (Cocos nucifera L.) currently faces a substantial gap between demand and production. Current plantings of this crop are aging, and these traditional varieties are susceptible to several devastating pests and diseases. Consequently, there is an urgent need to replant and expand coconut lands with new, genetically superior varieties. Such replanting cannot be met through the conventional method of seed nut planting, and tissue culture has emerged as a likely solution to address this problem. However, due to certain technical barriers, elevated costs, and a need for improved efficiency, the development of automated and highly efficient tissue culture techniques is yet to be developed. The present research explores the potential of an in vitro temporary immersion system (TIS) to improve the production of somatic embryogenic callus for plantlet regeneration. Results indicated that, in comparison to the conventional agar-based method used to produce coconut somatic embryogenic callus, the TIS method significantly enhanced embryogenic callus production. The optimal biomass of callus for inoculating the TIS was determined to be 0.2 g in each 900 mL vessel and the most favorable embryogenic developmental stage for employing TIS was the globular stage of embryo development. The most effective immersion time to give the highest yield of embryogenic callus was 5 min every 6 h. This foundational research demonstrates that a TIS step is likely to be important to rapidly produce, on a large scale, coconut plantlets to meet the escalating demand for materials for the replanting of coconut lands. [ABSTRACT FROM AUTHOR]

Pinus massoniana is a critical afforestation and ecological tree species in China. However, the continued existence of this pine is severely threatened by pine wilt disease. Somatic embryogenesis serves as a highly efficient clonal propagation approach. Although significant progress has been made in somatic embryogensis research on P. massoniana, resulting in the successful regeneration of plants, the limited embryogenic potential of improved cell lines and loss of embryogenic properties resulting from prolonged proliferation have posed obstacles to the industrialization of SE production. In this study, we investigated the effect of phytosulfokine on embryo development of cell lines from P. massoniana which lead to a cascade of physicochemical changes. Eight embryogenic cell lines of P. massoniana were used to observe phenotype and cytological changes. Physiological factors and the contents of nutrients and endogenous hormones were measured before and after phytosulfokine addition. We found that PSK promoted a change in the embryogenic mass of P. massoniana, leading to their development from pro-embryogenic mass (PEM)I to PEMII or PEMIII stages of pro-embryos. In addition, PSK accumulated soluble sugar, protein, and starch, and maintained redox homeostasis during cell line proliferation by reducing H2O2 levels. Our findings increase our understanding of how PSK affects somatic embryogensis in P. massoniana, thereby providing a valuable tool for establishing efficient somatic embryogensis systems in conifer species.Key message: This study aimed to evaluate the effect of exogenously supplemented PSK on the proliferation and embryo development of different cell lines from P. massoniana. [ABSTRACT FROM AUTHOR]

Background: Somatic embryogenesis (SE) exemplifies the unique developmental plasticity of plant cells. The regulatory processes, including epigenetic modifications controlling embryogenic reprogramming of cell transcriptome, have just started to be revealed. Results: To identify the genes of histone acetylation-regulated expression in SE, we analyzed global transcriptomes of Arabidopsis explants undergoing embryogenic induction in response to treatment with histone deacetylase inhibitor, trichostatin A (TSA). The TSA-induced and auxin (2,4-dichlorophenoxyacetic acid; 2,4-D)-induced transcriptomes were compared. RNA-seq results revealed the similarities of the TSA- and auxin-induced transcriptomic responses that involve extensive deregulation, mostly repression, of the majority of genes. Within the differentially expressed genes (DEGs), we identified the master regulators (transcription factors - TFs) of SE, genes involved in biosynthesis, signaling, and polar transport of auxin and NITRILASE-encoding genes of the function in indole-3-acetic acid (IAA) biosynthesis. TSA-upregulated TF genes of essential functions in auxin-induced SE, included LEC1/LEC2, FUS3, AGL15, MYB118, PHB, PHV, PLTs, and WUS/WOXs. The TSA-induced transcriptome revealed also extensive upregulation of stress-related genes, including those related to stress hormone biosynthesis. In line with transcriptomic data, TSA-induced explants accumulated salicylic acid (SA) and abscisic acid (ABA), suggesting the role of histone acetylation (Hac) in regulating stress hormone-related responses during SE induction. Since mostly the adaxial side of cotyledon explant contributes to SE induction, we also identified organ polarity-related genes responding to TSA treatment, including AIL7/PLT7, RGE1, LBD18, 40, HB32, CBF1, and ULT2. Analysis of the relevant mutants supported the role of polarity-related genes in SE induction. Conclusion: The study results provide a step forward in deciphering the epigenetic network controlling embryogenic transition in somatic cells of plants. [ABSTRACT FROM AUTHOR]

This document is an editorial from the International Journal of Molecular Sciences discussing recent advances in plant somatic embryogenesis. Somatic embryogenesis is a process in which somatic cells undergo changes to form structures called somatic embryos, which can develop into plants. The article explores the applications of somatic embryogenesis in clonal propagation, genetic modification, and plant genome editing. It also discusses the use of somatic embryos in cryopreservation and the study of molecular mechanisms in plant development. The editorial highlights various studies on the induction of somatic embryogenesis, the role of transcription factors, the influence of auxins, and the practical applications of somatic embryogenesis in forest management and breeding programs. The authors conclude that while somatic embryogenesis is a powerful tool in plant biotechnology, further interdisciplinary research is needed to address remaining challenges. [Extracted from the article]

CD4+CD25+Foxp3+ regulatory T cells (Treg) have been implicated in pain modulation in various inflammatory conditions. However, whether Treg cells hamper pain at steady state and by which mechanism is still unclear. From a meta-analysis of the transcriptomes of murine Treg and conventional T cells (Tconv), we observe that the proenkephalin gene (Penk), encoding the precursor of analgesic opioid peptides, ranks among the top 25 genes most enriched in Treg cells. We then present various evidence suggesting that Penk is regulated in part by members of the Tumor Necrosis Factor Receptor (TNFR) family and the transcription factor Basic leucine zipper transcription faatf-like (BATF). Using mice in which the promoter activity of Penk can be tracked with a fluorescent reporter, we also show that Penk expression is mostly detected in Treg and activated Tconv in noninflammatory conditions in the colon and skin. Functionally, Treg cells proficient or deficient for Penk suppress equally well the proliferation of effector T cells in vitro and autoimmune colitis in vivo. In contrast, inducible ablation of Penk in Treg leads to heat hyperalgesia in both male and female mice. Overall, our results indicate that Treg might play a key role at modulating basal somatic sensitivity in mice through the production of analgesic opioid peptides. [ABSTRACT FROM AUTHOR]

The First International Virtual Exchange between African and New Zealand Researchers IVEANZR hosted by the University of Canterbury (NZ) was held via Zoom over 2 h on 15 May 2024. There was no registration fee for the conference. The purpose of the virtual conference was to provide a forum for postgraduate students and researchers to present their latest research in an international conference environment but without the burden of a registration fee and the prohibitive cost of international travel, particularly for many emerging researchers. There were 148 registered participants from several countries in the conference and nine presentations were made successfully. The successful event supports the notion that a conference held virtually is a sustainable, low carbon emission, interactive way to share knowledge across international borders. [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs) possess strange optical, electrical, and magnetic properties, which arise from their quantum size effects. Nanotechnology, with its immense potential, offers immediate solutions to address these challenges and benefit our society. The pressing concerns of climate change and improving nutritional quality need that we adapt to changing conditions. These distinctive characteristics open up exciting opportunities for the development of innovative sensing techniques that allow for the real-time monitoring of plant responses to nanomaterial exposure. Plant tissue culture is an essential pillar in the field of plant biology, serving as a crucial foundation for a wide range of important applications. This remarkable technique plays a vital role in various areas, such as plant preservation, facilitating large-scale reproduction, enabling genetic modification, fostering the production of bioactive compounds, and enhancing desirable plant characteristics. Through the intricate process of tissue culture, scientists and researchers can manipulate plant cells in a controlled environment, opening up endless possibilities for advancing our understanding of plants and harnessing their potential for benefits. Understanding and optimization of these factors is crucial for improving the efficiency of in vitro propagation. In recent times, the integration of nanoparticles (NPs) has emerged as a successful strategy to combat microbial contaminants in explants, while also showcasing their positive impact on callus initiation, organogenesis, somatic embryogenesis, explants sterilization, and the production of secondary metabolites. This comprehensive review aims to consolidate the significant advancements achieved throughout the integration of nanotechnology into plant tissue culture. It seeks to shed light on the positive attributes associated with the consumption of nanoparticles (NPs) in plant tissue culture, highlighting their enormous potential and benefits. [ABSTRACT FROM AUTHOR]

Plant growth regulators play a crucial role in the proliferation of protocorm-like bodies through somatic embryogenesis in Phalaenopsis orchids. Additionally, media components and cultural systems can impact their proliferation and reduce costs. This research aimed to enhance proliferation rates of orchid protocorm–like bodies and decrease costs of both media providing and culture systems. To achieve this, protocorm explants were cultivated in four different systems: solid, liquid permanent immersion (Erlenmeyer flasks on a shaker), and temporary immersion (RITA® and FA-Bio bioreactor, a new laboratory mini-bioreactor). The media used included half-strength Murashige and Skoog (1/2 MS), modified FAST medium (MFAST), and low-cost medium (LC). The solid medium contained thidiazuron at concentrations of 0, 1.5, or 3.0 mg L−1. Solid 1/2 MS without thidiazuron was the control. Protocorm-like bodies in solid LC and MFAST exhibited high chlorophyll and anthocyanin content. Their proliferation rates increased by 32.6% and 29.6%, respectively, while culture costs decreased by 45.2% and 43.1%, respectively, compared to solid 1/2 MS with 3.0 mg L−1 thidiazuron. The production of protocorm-like bodies and their carbohydrate content were significantly higher in MFAST and LC media, compared to 1/2 MS media across all culture systems. The RITA® bioreactor with liquid LC showed higher proliferation rates than the other treatments. Liquid LC reduced costs by 57.6% compared to solid LC, making it a cost-effective option for mass propagation. The FA-Bio bioreactor reduced costs by 70.5% compared to RITA® for laboratory research evaluations in liquid culture. MFAST media in FA-Bio bioreactors can be used commercially for cost-effective propagation of Phalaenopsis orchids. [ABSTRACT FROM AUTHOR]

Paspalum notatum Flüggé is a subtropical grass native from the Americas and one of the main components of the subtropical South American grasslands. Although P. notatum exhibits a high forage productivity and persistence, some limitations are observed in the species, such as forage quality due to high lignin content. The development of efficient tissue culture and plant transformation protocols in cultivars for forage production are necessary to embrace novel genetic improvement through transgenesis and genome editing. Efficient regeneration and transformation systems for many plant species can be hampered by genotype dependency, which can only be determined through extensive laboratory testing and evaluation. In this study, various factors extracted from protocols have been evaluated to establish efficient somatic embryogenesis, plant regeneration, and genetic transformation in apomictic initial variety INIA Sepé. Optimal somatic embryogenesis and regeneration from explant sources, such as mature seeds and meristematic tissue derived from in vitro propagated tillers, ranged between 79 and 88%. Microprojectile bombardment of two plasmids encoding a constitutively regulated reporter gene and nptII selectable marker expression constructs showed an average transformation efficiency of 10.3% from meristematic tissue as an explant source. Furthermore, the constitutive promoters, 35S and ZmUbi, were tested in GFP transient expression assays to evaluate optimal cassettes for transgene(s) expression. Translation of a wheat codon–optimized Cas9 sequence using Cas9:2A:tuGFP fusion protein was also tested in protoplasts. The information generated on promoter activity and Cas9 translation, and the establishment of an efficient transformation system, provided useful tools for future work in genetic engineering and genome editing in P. notatum cv. INIA Sepé. [ABSTRACT FROM AUTHOR]

The regeneration of plant somatic cells is a prerequisite for their biological breeding. Identification of key genes controlling embryogenic callus (EC) differentiation and investigation of the genetic mechanism of cell fate determination are important for improving plant variety. In this study, we used the maize inbred line KN5585 and its gene-edited mutants Zmprx19-1, Zmprx19-2 and Zmprx19-3 as plant materials. Three somatic regeneration-related traits, the embryogenic callus induction rate (EIR), green callus rate (GCR) and plantlet regeneration rate (PRR), were identified by tissue culture of immature embryos. Additionally, the ECs at different differentiation stages (0 d, 5 d, 10 d and 15 d) were subjected to RNA-seq, and comparative transcriptome analyses were performed. The results showed that the somatic regeneration traits of the mutants were all highly significantly lower than those of the wild type (p < 0.01). The PRR value of KN5585 was 75.25%, while the highest PRR of the mutants was only 15.08%, indicating that knockdown of ZmPRX19 inhibited EC regeneration. Transcriptome sequencing yielded a total of 200.30 Gb of clean data from 24 libraries, with an average of 6.53 Gb of clean data per library. Mutant and wild-type gene expression data were compared separately at four differentiation stages, and 689 common differentially expressed genes (DEGs) were screened. WGCNA was used to classify these genes into nine modules, which were subsequently subjected to GO and KEGG enrichment analyses. In total, 40, 23, 17 and 5 genes were significantly (q < 0.05) enriched in plant hormone signal transduction, the MAPK signaling pathway-plant, phenylpropanoid biosynthesis and photosynthesis, respectively. Moreover, protein–protein interaction (PPI) network analysis revealed five MAPKKK17_18 hub nodes involved in the MAPK pathway-plant, which may be the key genes controlling plantlet differentiation from ECs. The above results provide a basis for the final elucidation of the molecular mechanism of plant somatic regeneration. [ABSTRACT FROM AUTHOR]

SUMMARY: Citrus is a model plant for studying adventitious embryos, a form of asexual reproduction controlled by a single dominant gene, RWP. This gene has been identified as the causal gene for nucellar embryogenesis, but its function has not yet been fully understood. In this study, we used the fast‐growing Fortunella hindsii as a system to explore chromatin accessibility during the nucellar embryony initiation, emphasizing elevated chromatin accessibility in polyembryonic (PO) genotypes compared to monoembryonic ones (MO). Notably, a higher level of accessible chromatin was observed in one allele of the promoter region of FhRWP, consistent with increased expression of the allele carrying the causal structural variant. By independently performing RNAi and gene editing experiments on PO genotypes, we found the downregulation of FhRWP expression could reduce the number of nucellar embryos, while its knockout resulted in abnormal axillary bud development. In overexpression experiments, FhRWP was identified as having the unique capability of inducing the embryogenic callus formation in MO stem segments, possibly through the regulation of the WUS‐CLV signaling network and the ABA and cytokinin pathway, marking the inaugural demonstration of FhRWP's potential to reignite somatic cells' embryogenic fate. This study reveals the pleiotropic function of RWP in citrus and constructs a regulatory network during adventitious embryo formation, providing a new tool for bioengineering applications in plant regeneration. Significance Statement: FhRWP plays a central role in regulating multiple developmental phenotypes, including axillary bud differentiation, nucellar embryo formation, and somatic embryogenesis in citrus. [ABSTRACT FROM AUTHOR]

Somatic embryogenesis (SE) is a biotechnological tool used to generate new individuals and is the preferred method for rapid plant regeneration. However, the molecular basis underlying somatic cell regeneration through SE is not yet fully understood, particularly regarding interactions between the proteome and post-translational modifications. Here, we performed association analysis of high-throughput proteomics and phosphoproteomics in three representative samples (non-embryogenic calli, NEC; primary embryogenic calli, PEC; globular embryos, GE) during the initiation of plant regeneration in cotton, a pioneer crop for genetic biotechnology applications. Our results showed that protein accumulation is positively regulated by phosphorylation during SE, as revealed by correlation analyses. Of the 1418 proteins that were differentially accumulated in the proteome and the 1106 phosphoproteins that were differentially regulated in the phosphoproteome, 115 proteins with 229 phosphorylation sites overlapped (co-differential). Furthermore, seven dynamic trajectory patterns of differentially accumulated proteins (DAPs) and the correlated differentially regulated phosphoproteins (DRPPs) pairs with enrichment features were observed. During the initiation of plant regeneration, functional enrichment analysis revealed that the overlapping proteins (DAPs-DRPPs) were considerably enriched in cellular nitrogen metabolism, spliceosome formation, and reproductive structure development. Moreover, 198 DRPPs (387 phosphorylation sites) were specifically regulated at the phosphorylation level and showed four patterns of stage-enriched phosphorylation susceptibility. Furthermore, enrichment annotation analysis revealed that these phosphoproteins were significantly enriched in endosomal transport and nucleus organization processes. During embryogenic differentiation, we identified five DAPs-DRPPs with significantly enriched characteristic patterns. These proteins may play essential roles in transcriptional regulation and signaling events that initiate plant regeneration through protein accumulation and/or phosphorylation modification. This study enriched the understanding of key proteins and their correlated phosphorylation patterns during plant regeneration, and also provided a reference for improving plant regeneration efficiency. [ABSTRACT FROM AUTHOR]

In the world's flower trade, gladiolus (Gladiolus spp.) is ranked first among bulbous flowers and eighth among cut flowers, with more than 30,000 different cultivars being grown. Mass multiplication and commercialization are restricted by the traditional propagation methods. However, the large-scale proliferation and improvement of the gladiolus have been accomplished with the aid of plant tissue culture and other biotechnological techniques. The current review includes a thorough examination of the growth and development parameters required for successful in vitro gladiolus development as well as cormel formation. Moreover, focus is being given to various techniques and methods such as in vitro cytogenetic stability and modification of chromosome number, in vitro mutagenesis and selection of pest resistance, in vitro identification and selection to develop virus-free germplasm, cryopreservation, synthetic seed technology, identifying virus diseases by RT-PCR, somaclonal variation, and protoplast and somatic hybridization. Molecular markers and their applications for genetic diversity analysis, relationships between different genotypes, and clonal stability analysis in Gladiolus species have been conducted by several research groups worldwide and are also being discussed. The article also covers efforts to enhance the functionality of plant phenotypes through genetic transformation. Future prospects for further improvement of ornamental gladiolus are also explored. Overall, the current review provides insight into the applications of basic and advanced biotechnological tools for gladiolus improvement. [ABSTRACT FROM AUTHOR]

Panax vietnamensis Ha et Grushv., commonly known as Vietnamese ginseng or Ngoc Linh ginseng, is a notable species within the Panax genus. In Vietnamese traditional medicine, Ngoc Linh ginseng is revered as a ‘miraculous medicine,’ famed for enhancing physical strength and treating a variety of health conditions. The application of in vitro tissue culture techniques to medicinal plants is acknowledged as a strategic method for generating bioactive specialized metabolites. This comprehensive review highlights the properties of Vietnamese ginseng and emphasizes recent progress in various in vitro tissue culture techniques, including callus induction, somatic embryo induction, cell cultivation in suspension, hairy root cultivation, and adventitious root cultivation. Moreover, the review addresses the challenges and potential future developments related to these techniques. The exploration of these in vitro practices has laid the groundwork for the commercial exploitation of Vietnamese ginseng, facilitating the swift and effective production of both ginseng biomass and its bioactive compounds. [ABSTRACT FROM AUTHOR]

Coconut palm is of great economic importance and contributes to income generation, employment, nutrition and food security in the commercial sector. Malaysia, which is among the top 10 coconut-producing countries in the world, plays a notable role, while Indonesia is the largest producer. The Matag coconut, a hybrid of the Malayan Yellow Dwarf and Tagnanan Tall varieties, is characterised by its excellent nut quality and higher yield of 25,000 to 30,000 nuts per hectare annually. Despite its fame, the Matag coconut has faced problems, particularly disease susceptibility, which has been accelerated by globalisation and has led to the extinction of many crops. Somatic embryogenesis, an in vitro breeding technique, is a promising avenue for coconut regeneration and micropropagation. However, the genotype dependence and high heterozygosity of coconut lead to variability among the progeny, which limits the effectiveness of this method. The conventional use of fluorescent lamps for in vitro propagation, which are customised to the needs of the plants, has disadvantages such as the generation of unnecessary wavelengths and high energy consumption. The integration of the thin cell layer (TCL) method into tissue culture, particularly via the organogenesis route, is proving to be a transformative technique for coconut propagation. This review highlights the potential enhancement of this novel approach through the use of red and blue light-emitting diodes (LEDs). The use of these LEDs aims to optimise the propagation and acclimatisation of the ‘Matag’ coconut and offers a viable solution for both research and commercial applications. [ABSTRACT FROM AUTHOR]

Abstract Background Somatic embryogenesis (SE) exemplifies the unique developmental plasticity of plant cells. The regulatory processes, including epigenetic modifications controlling embryogenic reprogramming of cell transcriptome, have just started to be revealed. Results To identify the genes of histone acetylation-regulated expression in SE, we analyzed global transcriptomes of Arabidopsis explants undergoing embryogenic induction in response to treatment with histone deacetylase inhibitor, trichostatin A (TSA). The TSA-induced and auxin (2,4-dichlorophenoxyacetic acid; 2,4-D)-induced transcriptomes were compared. RNA-seq results revealed the similarities of the TSA- and auxin-induced transcriptomic responses that involve extensive deregulation, mostly repression, of the majority of genes. Within the differentially expressed genes (DEGs), we identified the master regulators (transcription factors - TFs) of SE, genes involved in biosynthesis, signaling, and polar transport of auxin and NITRILASE-encoding genes of the function in indole-3-acetic acid (IAA) biosynthesis. TSA-upregulated TF genes of essential functions in auxin-induced SE, included LEC1/LEC2, FUS3, AGL15, MYB118, PHB, PHV, PLTs, and WUS/WOXs. The TSA-induced transcriptome revealed also extensive upregulation of stress-related genes, including those related to stress hormone biosynthesis. In line with transcriptomic data, TSA-induced explants accumulated salicylic acid (SA) and abscisic acid (ABA), suggesting the role of histone acetylation (Hac) in regulating stress hormone-related responses during SE induction. Since mostly the adaxial side of cotyledon explant contributes to SE induction, we also identified organ polarity-related genes responding to TSA treatment, including AIL7/PLT7, RGE1, LBD18, 40, HB32, CBF1, and ULT2. Analysis of the relevant mutants supported the role of polarity-related genes in SE induction. Conclusion The study results provide a step forward in deciphering the epigenetic network controlling embryogenic transition in somatic cells of plants.

Salinity stress is a major abiotic stress factor that affects plant growth, physiological activities and developmental processes. This study involves establishing efficient somatic embryogenesis and plantlet regeneration system using immature inflorescence of kodo millet (Paspalum scrobiculatum L. cv. TNAU86) under NaCl-salinity stress conditions. To begin with, the immature inflorescence (0.5cm) of kodo millet was excised from the 40-45 days old field growing plants followed by surface sterilization and inoculation in Murashige and Skoog (MS) medium supplemented with the various concentrations of NaCl (10mM, 25mM, 50mM, 75mM, 100mM, 150mM, and 200mM) salt along with 2,4-Dichlorophenoxyacetic acid (2,4-D) (1.5 mg/L). The results reveal that the maximum mean frequency (89.3±0.3%) of somatic embryogenesis was obtained from embryogenic callus that was growing with medium added with NaCl (50mM) while it was found to be the least mean frequency (12±4.1%) with 150mM of NaCl-salt treatments. Moreover, the highest concentration of NaCl (200mM) salinity was found to be lethal and explants were observed to get gradually necrosed. Later, embryogenic calli showing differentiation of somatic embryos were sub-cultured on basal medium supplemented with 0.5mg/L of 6-Benzylaminopurine (BAP) along with respective concentrations of NaCl-salt for the germination of somatic embryos into plantlets. Significantly, 100mM of NaCl-treatment was proved to show strong inhibitions and thus minimum salt tolerant plantlets regeneration (4±2.21%) was recorded. Further, in vitro grown salinity stress tolerant plantlets were transferred to plastic cups and gradually acclimatized under greenhouse conditions.

This study was conducted to establish an efficient in vitro regeneration technique for the induction of somatic embryo and plantlet regeneration under NaCl-salt stress conditions in black rice (Oryza sativa. L., cv Co57), a traditional Indian cereal food. Embryogenic calli were obtained from mature caryopsis culture on Murashige and Skoog (1962) medium fortified with 2,4-dichlorophenoxyacetic acid (2.0mg/L) either alone or in combination with various concentrations of NaCl (10mM, 25mM, 50mM, and 100mM) in order to induce the salt tolerant somatic embryo differentiation. Furthermore, embryogenic calli were found to show shoot regeneration on MS-medium fortified with 2.0mg/L of 6-benzylaminopurine (BAP) in combination with 0.5mg/L of α-naphthaleneacetic acid (NAA) and in presence of NaCl (10mM, 25mM, 50mM, and 100mM). Significantly, the high concentration (150mM) of NaCl was proved to be lethal for both somatic embryogenesis as well as plantlets regeneration. Moreover, the low frequency (40.3%) of somatic embryogenesis and minimum number of salt tolerant somatic embryos per callus (3.2±0.1) was recorded with the caryopsis explants that were treated with the high concentration (100mM) of NaCl-salt added embryo induction medium. Significantly, low frequency of salt-tolerant plantlets regeneration (25%) and minimum number of plantlets per embryogenic callus (1.5±0.1) was recorded in the embryogenic callus that was treated with 100mM of NaCl in regeneration medium containing BAP (2.0mg/L) in combination with NAA (0.5mg/L). Further, salinity tolerant plantlets were transferred to soil and gradually acclimatized under growth chamber conditions. This study thus offers a suitable technique for production of salt tolerant black rice, an alternative approach for the traditional Indian black rice crop improvements.

The Pisifera type oil palm is an important palm variety and mostly used as a pollen source to produce Tenera commercial hybrid varieties. This research on proliferating fertile Pisifera oil palm callus using somatic embryogenesis method was conducted at the Tissue Culture Laboratory of PT. Sampoerna Agro, Tbk from February to August 2021 to find out the optimum basal media and the concentration of growth regulators on callus proliferation. The planting material was the primary callus from the previous research. This study used a factorial Completely Randomized Design with two factors. The first factor involved two types of basal media: MS and Y3, and the second factor consisted of different concentrations of growth regulators (PGR). All treatments were repeated three times. The results showed that the use of MS media supplemented with 6 mg/l NAA and 0.5 mg/l 2,4-D was the most effective treatment for the proliferation of embryogenic callus in term of callus initiation time, the capacity of primary callus formation, primary calli morphology and proliferation, and callus fresh weight.

Abstract Background Somatic embryogenesis (SE) is recognized as a promising technology for plant vegetative propagation. Although previous studies have identified some key regulators involved in the SE process in plant, our knowledge about the molecular changes in the SE process and key regulators associated with high embryogenic potential is still poor, especially in the important fiber and energy source tree – eucalyptus. Results In this study, we analyzed the transcriptome and proteome profiles of E. camaldulensis (with high embryogenic potential) and E. grandis x urophylla (with low embryogenic potential) in SE process: callus induction and development. A total of 12,121 differentially expressed genes (DEGs) and 3,922 differentially expressed proteins (DEPs) were identified in the SE of the two eucalyptus species. Integration analysis identified 1,353 (131 to 546) DEGs/DEPs shared by the two eucalyptus species in the SE process, including 142, 13 and 186 DEGs/DEPs commonly upregulated in the callus induction, maturation and development, respectively. Further, we found that the trihelix transcription factor ASR3 isoform X2 was commonly upregulated in the callus induction of the two eucalyptus species. The SOX30 and WRKY40 TFs were specifically upregulated in the callus induction of E. camaldulensis. Three TFs (bHLH62, bHLH35 isoform X2, RAP2-1) were specifically downregulated in the callus induction of E. grandis x urophylla. WGCNA identified 125 and 26 genes/proteins with high correlation (Pearson correlation > 0.8 or < -0.8) with ASR3 TF in the SE of E. camaldulensis and E. grandis x urophylla, respectively. The potential target gene expression patterns of ASR3 TF were then validated using qRT-PCR in the material. Conclusions This is the first time to integrate multiple omics technologies to study the SE of eucalyptus. The findings will enhance our understanding of molecular regulation mechanisms of SE in eucalyptus. The output will also benefit the eucalyptus breeding program.

Abstract Background Angelica Gigas (Purple parsnip) is an important medicinal plant that is cultivated and utilized in Korea, Japan, and China. It contains bioactive substances especially coumarins with anti-inflammatory, anti-platelet aggregation, anti-cancer, anti-diabetic, antimicrobial, anti-obesity, anti-oxidant, immunomodulatory, and neuroprotective properties. This medicinal crop can be genetically improved, and the metabolites can be obtained by embryonic stem cells. In this context, we established the protoplast-to-plant regeneration methodology in Angelica gigas. Results In the present investigation, we isolated the protoplast from the embryogenic callus by applying methods that we have developed earlier and established protoplast cultures using Murashige and Skoog (MS) liquid medium and by embedding the protoplast in thin alginate layer (TAL) methods. We supplemented the culture medium with growth regulators namely 2,4-dichlorophenoxyaceticacid (2,4-D, 0, 0.75, 1.5 mg L− 1), kinetin (KN, 0, 0.5, and 1.0 mg L− 1) and phytosulfokine (PSK, 0, 50, 100 nM) to induce protoplast division, microcolony formation, and embryogenic callus regeneration. We applied central composite design (CCD) and response surface methodology (RSM) for the optimization of 2,4-D, KN, and PSK levels during protoplast division, micro-callus formation, and induction of embryogenic callus stages. The results revealed that 0.04 mg L− 1 2,4-D + 0.5 mg L− 1 KN + 2 nM PSK, 0.5 mg L− 1 2,4-D + 0.9 mg L− 1 KN and 90 nM PSK, and 1.5 mg L− 1 2,4-D and 1 mg L− 1 KN were optimum for protoplast division, micro-callus formation and induction embryogenic callus. MS basal semi-solid medium without growth regulators was good for the development of embryos and plant regeneration. Conclusions This study demonstrated successful protoplast culture, protoplast division, micro-callus formation, induction embryogenic callus, somatic embryogenesis, and plant regeneration in A. gigas. The methodologies developed here are quite useful for the genetic improvement of this important medicinal plant.

Vegetable oil production from oil palm (Elaeis guineensis Jacq.) is an important industry due to the rising demand every year. The somatic embryogenesis culture can propagate oil palm duplicate as parent plant, which can be selected as breeding material to produce new planting germplasm with high production or disease resistance. This study aims to evaluate the genotypic effect of somatic embryogenesis, while immature leaflets were employed as explants. The culture used embryo induction medium based on Murashige and Skoog (MS) modifications that contained 5 ​mg/L Naphthalene Acetic acid (NAA) and 0.5 ​mg/L Benzyl Amino Purine (BAP). The genotypic effect was statistically significant in the percentage of callus induction, producing somatic embryos, and germination embryos. In this study, we successfully cloned thirteen oil palm genotypes (GE-02, GE-03, GE-06, GE-07, GE-09, GE-23, GE-24, GE-27, GE-28, GE-32, GE-33, GE-34, and GE-35), with the highest number of somatic embryos formed on GE-27 with a percentage of 70.1%. The cloning was successful in accelerating the propagation of oil palm for materials breeding programs to create new varieties with high production and disease resistance. It is necessary to observation the performance of these clones in the field in terms of mantle flower appearance.

Although hyperactivity is associated with a wide variety of neurodevelopmental disorders, the early embryonic origins of locomotion have hindered investigation of pathogenesis of these debilitating behaviors. The earliest motor output in vertebrate animals is generated by clusters of early-born motor neurons (MNs) that occupy distinct regions of the spinal cord, innervating stereotyped muscle groups. Gap junction electrical synapses drive early spontaneous behavior in zebrafish, prior to the emergence of chemical neurotransmitter networks. We use a genetic model of hyperactivity to gain critical insight into the consequences of errors in motor circuit formation and function, finding that Fragile X syndrome model mutant zebrafish are hyperexcitable from the earliest phases of spontaneous behavior, show altered sensitivity to blockade of electrical gap junctions, and have increased expression of the gap junction protein Connexin 34/35. We further show that this hyperexcitable behavior can be rescued by pharmacological inhibition of electrical synapses. We also use functional imaging to examine MN and interneuron (IN) activity in early embryogenesis, finding genetic disruption of electrical gap junctions uncouples activity between mnx1+ MNs and INs. Taken together, our work highlights the importance of electrical synapses in motor development and suggests that the origins of hyperactivity in neurodevelopmental disorders may be established during the initial formation of locomotive circuits. [ABSTRACT FROM AUTHOR]

Epigenetic aging clocks have been widely used to validate rejuvenation effects during cellular reprogramming. However, these predictions are unverifiable because the true biological age of reprogrammed cells remains unknown. We present an analytical framework to consider rejuvenation predictions from the uncertainty perspective. Our analysis reveals that the DNA methylation profiles across reprogramming are poorly represented in the aging data used to train clock models, thus introducing high epistemic uncertainty in age estimations. Moreover, predictions of different published clocks are inconsistent, with some even suggesting zero or negative rejuvenation. While not questioning the possibility of age reversal, we show that the high clock uncertainty challenges the reliability of rejuvenation effects observed during in vitro reprogramming before pluripotency and throughout embryogenesis. Conversely, our method reveals a significant age increase after in vivo reprogramming. We recommend including uncertainty estimation in future aging clock models to avoid the risk of misinterpreting the results of biological age prediction. [ABSTRACT FROM AUTHOR]

Animals and plants have developed resilience mechanisms to effectively endure and overcome physical damage and environmental challenges throughout their life span. To sustain their vitality, both animals and plants employ mechanisms to replenish damaged cells, either directly, involving the activity of adult stem cells, or indirectly, via dedifferentiation of somatic cells that are induced to revert to a stem cell state and subsequently redifferentiate. Stem cell research has been a rapidly advancing field in animal studies for many years, driven by its promising potential in human therapeutics, including tissue regeneration and drug development. A major breakthrough was the discovery of induced pluripotent stem cells (iPSCs), which are reprogrammed from somatic cells by expressing a limited set of transcription factors. This discovery enabled the generation of an unlimited supply of cells that can be differentiated into specific cell types and tissues. Equally, a keen interest in the connection between plant stem cells and regeneration has been developed in the last decade, driven by the demand to enhance plant traits such as yield, resistance to pathogens, and the opportunities provided by CRISPR/Cas-mediated gene editing. Here we discuss how knowledge of stem cell biology benefits regeneration technology, and we speculate on the creation of a universal genotype-independent iPSC system for plants to overcome regenerative recalcitrance. [ABSTRACT FROM AUTHOR]

Global climate change has already brought noticeable alterations to multiple regions of our planet, including increased CO2 concentrations and changes in temperature. Several important steps of plant growth and development, such as embryogenesis, can be affected by such environmental changes; for instance, they affect how stored nutrients are used during early stages of seed germination during the transition from heterotrophic to autotrophic metabolism—a critical period for the seedling's survival. In this article, we briefly describe relevant processes that occur during embryo maturation and account for nutrient accumulation, which are sensitive to environmental change. Most of the nutrients stored in the seed during its development—including carbohydrates, lipids, and proteins, depending on the species—accumulate during the seed maturation stage. It is also known that iron, a key micronutrient for various electron transfer processes in plant cells, accumulates during embryo maturation. The existing literature indicates that climate change can not only affect the quality of the seed, in terms of total nutritional content, but also affect seed production. We discuss the potential effects of temperature and CO2 increases from an embryo-autonomous point of view, in an attempt to separate the effects on the parent plant from those on the embryo. [ABSTRACT FROM AUTHOR]

Plant growth regulators (PGRs) play a vital role in the induction of morphogenesis in vitro. Synthetic PGRs are commonly used to induce organogenesis and somatic embryogenesis from various explants, while natural substances are rarely utilized. This study aimed to enhance the regenerative response in Nicotiana tabacum leaf explants using Tulsi (Ocimum sanctum) leaf extract and to elucidate the biochemical interactions during modulation of endogenous plant growth regulators, including indole-3-acetic acid (IAA), abscisic acid (ABA), zeatin, and 6-(γ, γ-dimethylallylamino) purine (2iP). Tulsi leaf extract significantly improved shoot production through interactions between endogenous hormones and those present in the extract, which enhanced stress mitigation. The 20% Tulsi leaf extract treatment produced significantly more shoots than the control, coinciding with increased endogenous IAA and zeatin levels starting on day 10 in culture. Furthermore, ABA and zeatin concentrations increased on days 15 and 25, respectively, in the 20% Tulsi extract treatment, suggesting their role in the induction of somatic embryo-like structures. ABA likely acts as an activator of stress responses, encouraging the development of these structures. Additionally, 2iP was involved in the induction of both forms of regeneration in the 10% and 20% extract treatments, especially in combination with ABA. These results suggest that Tulsi leaf extract holds promising potential as a natural supplement for increasing plant regeneration in vitro and advancing our understanding of how natural extracts of plant origin can be harnessed to optimize plant regeneration processes in vitro. [ABSTRACT FROM AUTHOR]

Plant biotechnology has become a viable strategy for agriculture, its applications include strategies aimed at obtaining and maintaining pathogen-free cultivars, genetic improvement (anther cultivation, embryo rescue, etc.) and micropropagation, used to obtain a greater number of individuals in less time and reduced spaces. Each of its phases depends largely on an adequate culture medium, since the growth, development and morphogenesis of the explant is mainly due to its chemical composition. For the production of garlic "seed" (Allium sativum L.), all phases are carried out in a growth chamber under automatically controlled aseptic and artificial conditions and at a temperature ranging between 22-25 °C. Somatic embryogenesis allows complete plants to be regenerated from a single cell. Garlic is an annual plant that only reproduces asexually, which is why bacteria, fungi and mainly viruses, which contribute to a 50-80 % decrease in its yield, affect it. An alternative to avoid these problems is the use of chemotherapy, thermotherapy or the combined use of one of these techniques with the cultivation of meristems, to obtain plants of high biological quality. Depending on the behavior of the culture during its in vitro stage, its response will be in the acclimatization phase and later in field conditions. This work was carried out with the objective of deepening the knowledge of some biotechnological techniques that are applied in the cultivation of garlic. [ABSTRACT FROM AUTHOR]

Tilletia horrida is an important soilborne fungal pathogen that causes rice kernel smut worldwide. We found a glycoside hydrolase family 128 protein, designated ThGhd_7, caused cell death in Nicotiana benthamiana leaves. The predicted signal peptide (SP) of ThGhd_7 targets it for secretion. However, loss of the SP did not affect its ability to induce cell death. The 23–201 amino acid sequence of ThGhd_7 was sufficient to trigger cell death in N. benthamiana. ThGhd_7 expression was induced and upregulated during T. horrida infection. ThGhd_7 localised to both the cytoplasm and nucleus of plant cells, and nuclear localisation was required to induce cell death. The ability of ThGhd_7 to trigger cell death in N. benthamiana depends on RAR1 (required for Mla12 resistance), SGT1 (suppressor of G2 allele of Skp1), and BAK1/SERK3 (somatic embryogenesis receptor‐like kinase 3). Heterologous overexpression of ThGhd_7 in rice reduced reactive oxygen species (ROS) production and enhanced susceptibility to T. horrida. Further research revealed that ThGhd_7 interacted with and destabilised OsSGT1, which is required for ROS production and is a positive regulator of rice resistance to T. horrida. Taken together, these findings suggest that T. horrida employs ThGhd_7 to disrupt ROS production and thereby promote infection. Summary Statement: Tilletia horrida is an important soilborne fungal pathogen that causes rice kernel smut (RKS) worldwide. This article finds that glycoside hydrolase family 128 protein ThGhd_7 suppressed host immune responses and thereby promoted T. horrida infection by modulating OsSGT1‐mediated reactive oxygen species (ROS) production. [ABSTRACT FROM AUTHOR]

Macrobrachium rosenbergii is the freshwater shrimp species of greatest economic interest, and its reproduction has been studied for commercial purposes. This study aimed to evaluate the effect of different salinities (0, 6, and 12 mg L-1) on the embryogenesis of this species. The females were observed daily according to their reproductive behavior. Upon the first sign of spawning, when their eggs were attached to the abdomen, they were collected for egg collection and transferred to the incubators at the respectively tested salinities. The eggs were collected every five days for up to 23 days, separated according to their stage of development, histologically processed, and stained for visualization of structural changes during embryogenesis using an optical microscope. From the egg's histological images at different embryonic development stages, the egg hatching time was evaluated, the changes that occurred in the eggs during embryogenesis, the total area of the eggs, the vacuole area, and the ratio between the vacuole area and the total area of the eggs. Differences were observed in hatching time, egg size, and vacuole area and area ratio. The 6 g L-1 of salinity treatment was statistically different from the other in all parameters analyzed. Therefore, it was concluded that 6 g L-1of salinity positively influenced embryogenesis, as it presented hatches from the 15th day of embryogenesis, demonstrating that there was a greater speed of migration of vitellogenin for the formation of the embryo, accelerating embryogenesis and hatching of M. rosenbergii. [ABSTRACT FROM AUTHOR]

SUMMARY: Medicago truncatula is a model legume for fundamental research on legume biology and symbiotic nitrogen fixation. Tnt1, a retrotransposon from tobacco, was used to generate insertion mutants in M. truncatula R108. Approximately 21 000 insertion lines have been generated and publicly available. Tnt1 retro‐transposition event occurs during somatic embryogenesis (SE), a pivotal process that triggers massive methylation changes. We studied the SE of M. truncatula R108 using leaf explants and explored the dynamic shifts in the methylation landscape from leaf explants to callus formation and finally embryogenesis. Higher cytosine methylation in all three contexts of CG, CHG, and CHH patterns was observed during SE compared to the controls. Higher methylation patterns were observed in assumed promoter regions (~2‐kb upstream regions of transcription start site) of the genes, while lowest was recorded in the untranslated regions. Differentially methylated promoter region analysis showed a higher CHH methylation in embryogenesis tissue samples when compared to CG and CHG methylation. Strong correlation (89.71%) was identified between the differentially methylated regions (DMRs) and the site of Tnt1 insertions in M. truncatula R108 and stronger hypermethylation of genes correlated with higher number of Tnt1 insertions in all contexts of CG, CHG, and CHH methylation. Gene ontology enrichment and KEGG pathway enrichment analysis identified genes and pathways enriched in the signal peptide processing, ATP hydrolysis, RNA polymerase activity, transport, secondary metabolites, and nitrogen metabolism pathways. Combined gene expression analysis and methylation profiling showed an inverse relationship between methylation in the DMRs (regions spanning genes) and the expression of genes. Our results show that a dynamic shift in methylation happens during the SE process in the context of CG, CHH and CHG methylation, and the Tnt1 retrotransposition correlates with the hyperactive methylation regions. Significance Statement: Dynamic shift in methylation happens during the somatic embryogenesis process in Medicago truncatula. [ABSTRACT FROM AUTHOR]

Pluripotent stem cells have the potential to generate embryo models that can recapitulate developmental processes in vitro. Large animals such as pigs may also benefit from stem-cell-based embryo models for improving breeding. Here, we report the generation of blastoids from porcine embryonic stem cells (pESCs). We first develop a culture medium 4FIXY to derive pESCs. We develop a 3D two-step differentiation strategy to generate porcine blastoids from the pESCs. The resulting blastoids exhibit similar morphology, size, cell lineage composition, and single-cell transcriptome characteristics to blastocysts. These porcine blastoids survive and expand for more than two weeks in vitro under two different culture conditions. Large animal blastoids such as those derived from pESCs may enable in vitro modeling of early embryogenesis and improve livestock species' breeding practices. [ABSTRACT FROM AUTHOR]

This document provides a summary of a special issue on the ornamental industry, which covers a wide range of topics related to plant propagation, defense mechanisms, tissue culture, genetics in urban planning, and emerging trends in the ornamental plant market. The research was conducted by authors from various countries, highlighting the global relevance of the industry. The authors hope that readers will find inspiration for further research in this field. The ornamental industry is a diverse and segmented industry that focuses on growing and marketing plants and cut flowers for decorative purposes. The global flower and ornamental plants market was valued at $27 billion in 2021 and is expected to increase in value by 2029. The industry faces challenges such as limited resources, climate change, sustainable pest and disease management, diversification of supply, and optimization of marketing and distribution. Breeding plays a crucial role in developing new cultivars, and advancements in genomics and gene editing have shown promise. Efficient systems for propagation, cultivation, and marketing are also important for the industry's success. [Extracted from the article]

Plants or tissues can be regenerated through various pathways. Like animal regeneration, cell totipotency and pluripotency are the molecular basis of plant regeneration. Detailed systematic studies on Arabidopsis thaliana gradually unravel the fundamental mechanisms and principles underlying plant regeneration. Specifically, plant hormones, cell division, epigenetic remodeling, and transcription factors play crucial roles in reprogramming somatic cells and reestablishing meristematic cells. Recent research on basal non-vascular plants and monocot crops has revealed that plant regeneration differs among species, with various plant species using distinct mechanisms and displaying significant differences in regenerative capacity. Conducting multi-omics studies at the single-cell level, tracking plant regeneration processes in real-time, and deciphering the natural variation in regenerative capacity will ultimately help understand the essence of plant regeneration, improve crop regeneration efficiency, and contribute to future crop design. [ABSTRACT FROM AUTHOR]

Garlic has been successfully propagated using various micropropagation methods both through direct and indirect organogenesis. In vitro micropropagation from the inflorescence, root tip somatic embryogenesis, shoot multiplication in liquid cultures, shoot tip culture, meristem culture, stem-disc dome culture, stem-disc culture has been reported. Therapeutic techniques have been deployed to produce planting material devoid of viruses. This review comprehends various factors affecting morphogenesis and propagule production in garlic. [ABSTRACT FROM AUTHOR]

Understanding the transcriptional regulatory characteristics throughout the embryogenesis of plant-parasitic nematodes is crucial for elucidating their developmental processes' uniqueness. However, a challenge arises due to the lack of suitable technical methods for synchronizing the age of plant-parasitic nematodes embryo, it is difficult to collect detailed transcriptome data at each stage of embryonic development. Here, we recorded the 11 embryonic developmental time-points of endophytic nematode Meloidogyne incognita (isolated from Wuhan, China), Heterodera glycines (isolated from Wuhan, China), and Ditylenchus destructor (isolated from Jinan, China) species, and constructed transcriptome datasets of single embryos of these three species utilizing low-input smart-seq2 technology. The datasets encompassed 11 complete embryonic development stages, including Zygote, 2-cell, 4-cell, 8-cell, 24–44 cell, 64–78 cell, Comma, 1.5-fold, 2-fold, Moving, and L1, each stage generated four to five replicates, resulting in a total of 162 high-resolution transcriptome libraries. This high-resolution cross-species dataset serves as a crucial resource for comprehending the embryonic developmental properties of plant-parasitic nematodes and for identifying functional regulatory genes during embryogenesis. [ABSTRACT FROM AUTHOR]

Global warming has adversely affected Picea abies (L.) H. Karst. forests in Europe, prompting the need for innovative forest-breeding strategies. Somatic embryogenesis (SE) offers promise but requires protocol refinement. Understanding the molecular mechanisms governing somatic embryo development is essential, as oxidative stress plays a crucial role in SE regulation. Ascorbic acid (ASA), is a vital antioxidant that can potentially control oxidative stress. In the present study, we normalized ASA concentrations in induction and proliferation media to enhance embryogenic tissue (ET) regeneration and proliferation capacity of mature explants. The media were supplemented with ASA at 0 mg l-1, 25mg l-¹ 50mg l-¹100 mg l-1, and 200 mg l-1. The accumulation of hydrogen peroxide (H2O2) and endogenous phytohormones, including auxins, cytokinins, brassinosteroids, abscisic acid, and gibberellin, was measured in non-embryonic calli and ET. Subsequently, their impact on ET induction and multiplication was analyzed. Our results demonstrate that application of ASA at concentrations of 25 mg l-¹ and 200 mg l-¹ led to increased H2O2 levels, potentially inducing oxidative stress while simultaneously reducing the levels of all endohormone groups. Notably, the highest ET induction frequency (approximately 70%) was observed for ASA at 50 mg l-1. These findings will enhance SE induction procedures, particularly in more resistant explants, underscoring the significance of ASA application to culture media. [ABSTRACT FROM AUTHOR]

Plants are dependent on divisions of stem cells to establish cell lineages required for growth. During embryogenesis, early division products are considered to be stem cells, whereas during post-embryonic development, stem cells are present in meristems at the root and shoot apex. PLETHORA/AINTEGUMENTA-LIKE (PLT/AIL) transcription factors are regulators of post-embryonic meristem function and are required to maintain stem cell pools. Despite the parallels between embryonic and post-embryonic stem cells, the role of PLTs during early embryogenesis has not been thoroughly investigated. Here, we demonstrate that the PLT regulome in the zygote, and apical and basal cells is in strong congruence with that of post-embryonic meristematic cells. We reveal that out of all six PLTs, only PLT2 and PLT4/BABY BOOM(BBM) are expressed in the zygote, and that these two factors are essential for progression of embryogenesis beyond the zygote stage and first divisions. Finally, we show that other PLTs can rescue plt2 bbm defectswhen expressed fromthe PLT2 andBBMpromoters, establishing upstream regulation as a key factor in early embryogenesis. Our data indicate that generic PLT factors facilitate early embryo development in Arabidopsis by induction of meristematic potential. [ABSTRACT FROM AUTHOR]