Plant Organs Research Articles

Modulation of cell differentiation and growth underlies the shift from bud protection to light capture in cauline leaves.

Plant organs have evolved into diverse shapes for specialized functions despite emerging as simple protrusions at the shoot apex. Cauline leaves serve as photosynthetic organs and protective structures for emerging floral buds. However, the growth patterns underlying this dual function remain unknown. Here, we investigate the developmental dynamics shaping Arabidopsis (Arabidopsis thaliana) cauline leaves underlying their functional diversification from other laminar organs. We show that cauline leaves display a significant delay in overall elongation compared to rosette leaves. Using live imaging, we reveal that their functional divergence hinges on early modulation of the timing of cell differentiation and cellular growth rates. In contrast to rosette leaves and sepals, cell differentiation is delayed in cauline leaves, fostering extended proliferation, prolonged morphogenetic activity, and growth redistribution within the organ. Notably, cauline leaf growth is transiently suppressed during the early stages, keeping the leaf small and unfolded during the initiation of the first flowers. Our findings highlight the unique developmental timing of cauline leaves, underlying their shift from an early protective role to a later photosynthetic function.

Bacterial Communities Associated with the Leaves and the Roots of Salt Marsh Plants of Bayfront Beach, Mobile, Alabama, USA.

Salt marshes are highly dynamic and biologically diverse ecosystems that serve as natural habitats for numerous salt-tolerant plants (halophytes). We investigated the bacterial communities associated with the roots and leaves of plants growing in the coastal salt marshes of the Bayfront Beach, located in Mobile, Alabama, United States. We compared external (epiphytic) and internal (endophytic) communities of both leaf and root plant organs. Using 16S rDNA amplicon sequencing methods, we identified 10 bacterial phyla and 59 different amplicon sequence variants (ASVs) at the genus level. Bacterial strains belonging to the phyla Proteobacteria, Bacteroidetes, and Firmicutes were highly abundant in both leaf and root samples. At the genus level, sequences of the genus Pseudomonas were common across all four sample types, with the highest abundance found in the leaf endophytic community. Additionally, Pantoea was found to be dominant in leaf tissue compared to roots. Our study revealed that plant habitat (internal vs. external for leaves and roots) was a determinant of the bacterial community structure. Co-occurrence network analyses enabled us to discern the intricate characteristics of bacterial taxa. Our network analysis revealed varied levels of ASV complexity in the epiphytic networks of roots and leaves compared to the endophytic networks. Overall, this study advances our understanding of the intricate composition of the bacterial microbiota in habitats (epiphytic and endophytic) and organs (leaf and root) of coastal salt marsh plants and suggests that plants might recruit habitat- and organ-specific bacteria to enhance their tolerance to salt stress.

Maize Responses to High Night Temperature During Postflowering and Early Grain Filling: Effects on Yield Components, Kernel Growth and Dry Matter Allocation

ABSTRACTWarm night frequency has increased steadily in the last years across maize production regions, but high night temperature (HNT) effects on growth, grain yield and maize dry matter allocation (DMA) to different plant organs remain poorly understood. In this study, we aimed to (i) analyse the DMA among reproductive and vegetative organs, (ii) evaluate the individual kernel weight through its determinants, rate and duration of grain filling and (iii) quantify changes in grain yield per plant and its components due to HNT during the postflowering and early grain‐filling period. Field‐grown maize was subjected to HNT induced by shelters during a 15‐ or 30‐day period after silking, encompassing the postflowering period (HNT15) and extending the heating into early grain filling (HNT30), respectively. The HNT was applied from 1900 to 0700 h while control plots remained at ambient night temperature (ANT). Kernel number per plant was decreased under both temperature regimes (i.e., HNT15 and HNT30); however, significant reductions in grain yield were only observed under HNT30. The DMA during the heating period was differentially affected by the duration of heating. While DMA to the stem was likewise reduced by both heating treatments, the partition to the uppermost ear was only reduced under HNT30. Related to the lack of response to HNT treatments of the rate and duration of grain filling, the individual kernel weight was not reduced. The source‐sink ratio was not affected by HNT, meanwhile, the apparent reserve use was significantly reduced under HNT30. Our results demonstrate that the magnitude of HNT effects is subjected to the duration of the heating period, but also depends on the intensity of heating explored across seasons, especially for kernel number and grain yield.

New Nitrogen Use Efficiency Indices for Biomass Formation and Productivity in Green Beans Under Foliar Fertilization with Molybdenum Nanofertilizer

Most crops are fertilized with high amounts of nitrogen, and have an alarmingly low utilization efficiency. For this reason, the coordination between the fertilizer contribution and the nitrogen requirements of the crop is very important. Therefore, the objective of the present study was to establish new indices to determine nitrogen use efficiency (NUE), and to define the amount of assimilated nitrogen, which is used for the formation of green bean plant organs, fertilized with molybdenum nanofertilizer applied foliarly, and combined with edaphic fertilization of ammonium nitrate. The plants were grown in a greenhouse covered with anti-aphid mesh and irrigated with nutrient solution. Three sources of foliar molybdenum (Nanofertilizer, molybdenum Chelate and Sodium Molybdate) were applied in four doses of 0, 5, 10 and 20 ppm Mo, complemented with edaphic fertilization of NH4NO3 (0, 3, 6 and 12 mM of N). As results, the NUE indices showed that with the application of the nanofertilizer, the total biomass production increased 41.65% more than with the application of the chelate, and 36.84% more than with the application of molybdate. In summary, the dose that presented the highest efficiency was 6 mM-N with 10 ppm-Mo. Finally, it is concluded that the use of NUE indices is an important approach that evaluates the fate of nitrogen and accurately estimates plant yield.

Diversity of endophytic bacteria in two banana cultivars and their potential for plant growth promoter

Abstract. Rahayu T, Purwestri YA, Subandiyah S, Sidiq Y, Widianto D. 2024. Diversity of endophytic bacteria in two banana cultivars and their potential for plant growth promoter. Biodiversitas 25: 2828-2838. The Klutuk banana plant (Musa balbisiana colla) is recognized as a resistant plant against biotic and abiotic stresses. The resistance trait of the cultivar is not exactly revealed but is most likely related to the presence of endophytic bacteria. This study aimed to determine the variation of banana cultivars and their organs on endophytic bacterial populations and their character as plant growth promoters (PGP). The study involved isolating endophytic bacteria from the root, corm, and petiole of cv. Klutuk and cv. Ambon, aged 4-5 months. Isolated endophytic bacteria were evaluated based on plant-growth-promoting (PGP) criteria. Subsequently, 16S rRNA sequences were amplified using 16S primers, 27f and 1492r, then sequenced. The obtained isolates were also identified by comparing the 16S sequences to the NCBI gene bank. The results showed that the population and number of isolates with the most PGP characters were in both banana cultivars' roots, petiole, and corm. Endophytic bacteria with multiple traits as PGP are composed of Phylum Proteobacteria (gamma, alpha, beta), Firmicutes, and Actinobacteria members. Several species are potential as they have multiple PGP traits with high-quantity test results, namely Microbacterium testaceum DSM 20166 strain, Simplicispira sp. CPCC 100842 strain, Klebsiella grimontii SB73 strain, Enterobacter mori LMG 25706 strain, Pantoea sp. CoA11 strain, Agrobacterium tumefaciens IAM 12048, Variovorax guangxiensis GXGD002 strain, Serratia nematodiphila DZ0503SBS1 strain, Bosea thiooxidans BI-42 strain, Erwinia tasmaniensis Et1/99 strain, Methylobacterium fujisawaense DSM 5686 strain, K2 isolate, K8 isolate, and K18 isolates. This study also revealed the endophytic bacterial population and character as plant organs influenced PGP. The roots and petioles became the banana plant organs colonized by endophytic bacteria with multiple traits as PGP. Overall, several isolates were discovered in cv. Klutuk were suspected of being new species with potential as PGP agents, and these were not identified in cv. Ambon.

Root morphology parameters and nutrient acquisition capabilities of grafted tomato plants in root-restricted conditions are subject to salinity and rootstock characteristics

ABSTRACT A tomato cultivar ('Izmir F1') grafted onto six commercially available rootstocks ('Arnold', 'Dohkko', 'Emperador', 'He-man', 'Kaiser', and 'Suzuka') together with self-grafted plants of the tomato cultivar (Izmir/Izmir) were included in a pot experiment. Growth, root morphology and nutrient uptake parameters were evaluated under different salinity conditions (0 and 50 mM NaCl). Grafting increases root length, specific root length, and root length ratio, which enhances the capabilities of hetero-grafted plants to exploit a larger volume of soil or otherwise increase root density under root restriction conditions. Since the root traits and nutrient concentrations in hetero-grafted variants were less impacted by a change in the salinity level, the use of specific rootstocks (‘Arnold,’ ‘Dohkko,’ ‘Kaiser’) could contribute to a steadier growth and yield of tomato plants under fluctuating salinity levels in the irrigation water. The hetero-grafted tomato plants (Dohkko/Izmir, Suzuka/Izmir) demonstrated higher Na sequestration/compartmentalization capabilities than the self-grafted (Izmir/Izmir) plants which helps to maintain a more appropriate K+/Na+ ratio. By exhibiting lower translocation indexes of some heavy metals (Al, Ni, Zn, and Cd), appropriate rootstock/scion combinations might be a useful tool for reducing the risk of their accumulation in edible plant organs.

Environmental aridity driving latitudinal pattern of biomass allocation fractions in root systems of 63 shrub species in dry valleys.

Fine roots and absorptive roots play key roles in acquiring resources throughout soil profiles and determining plant functions along environmental gradients. Yet, the geographical pattern of carbon allocation in fine roots, particularly in absorptive roots, and their relations with plant sizes and evironment are less understood. We sampled 243 xerophytic shrubs from 63 species distributed along the latitudinal gradient (23°N to 32°N) in dry valleys of southwest China and synthetically measured biomass fractions of plant organs, especially fine roots and absorptive roots (1st to 3rd root order). We identified latitudinal patterns of biomass allocation fractions of organs and their relationships with plant sizes and environmental factors. The latitudinal patterns of both absorptive root and fine-root fractions followed weak unimodal distributions; stem biomass fraction increased with the latitude, while the leaf biomass fraction decreased. The fraction of fine-root biomass had negative relationships with plant height and root depth. The fractions of root, fine root, and absorptive root biomass were largely explained by soil moisture. Furthermore, fraction of fine-root biomass increased in a relatively humid environment. Overall, soil moisture was the most important factor in driving latitudinal patterns of biomass fraction. Our study highlighted that functional redistribution of root system biomass was the critical adaptive strategy along a latitudinal gradient.

Production of betalains in plant cell and organ cultures: a review

Production of betalains in plant cell and organ cultures: a review

Pathway to Independence - an interview with Martina Cerise.

Martina Cerise is a postdoctoral fellow in the lab of George Coupland at the Max Planck Institute for Plant Breeding Research in Cologne, Germany. She is interested in using different plant organisms to understand the floral transition, which helps define plant architecture, and leads to fruit and seed production. Martina is one of the 2024 fellows of the Pathway to Independence Programme. We caught up with Martina to find out more about her research interests, her passion for science outreach and her plans as an independent group leader.

Connecting the Dots between GmPERK-1 and Enhanced Grain Weight in Glycine max

Large and distinct families of receptor-like kinases (RLKs) play elemental roles in many fundamental processes of plants. The proline-rich extensin-like receptor kinase (PERK) family is one of the most pivotal classes of RLKs. To date, there have been no comprehensive or published studies conducted on the PERK gene family in Glycine max. This research aimed to characterize the role of the PERK gene family in cultivated soybean using a systematic array of bioinformatic and experimental approaches. We identified 16 PERK members in G. max through local BLASTp, using PERK members from Arabidopsis thaliana as a query. Tissue expression of genes, predicted via tissue specific expression analysis from the soybean database “SoyBase”, revealed that these PERK genes exhibit differentiated expression patterns in various plant organs. The gene structure was predicted via Gene Structure Display Server (GSDS). Phylogeny was demonstrated through an evolutionary tree employing the neighbor-joining method. Subcellular localization of proteins was identified via “Softberry” and cis-acting elements were identified through PlantCARE. The KASP (Kompetitive Allele Specific PCR (KASP)) marker was developed for the GmPERK-1-C and GmPERK-1-T allele, targeting position 167 nt in the CDS region. Genotyping results indicated that GmPERK-1 exhibits promising potential for utilization in molecular breeding programs for soybean to increase crop yield. Collectively, our findings indicate that G. max accessions harboring the GmPERK-1-C allele exhibit significantly higher thousand grain weight compared to accessions carrying the GmPERK-1-T allele. This research enhances the understanding of the molecular roles of PERK genes in G. max, providing valuable insights for the utilization of favorable genetic variations in soybean molecular breeding programs.

Оздоровление растений винограда сорта Красностоп АЗОС от вируса скручивания листьев -1, -2 и -3 (grapevine leafroll-associated viruses -1, -2 and -3) методом термотерапии

Abstract. The grapevine leafroll-associated virus is one of the most harmful and economically significant. It is known from scientific literature sources that in the vineyards of the Krasnodar region this virus is spread over an area of 50 %. The problem of increasing the phytosanitary stability of grape plantations necessitates the constant improvement of protection systems, in which methods of improving planting material are of great importance. To date, there are several methods for inactivating viral particles and freeing individual plant organs from viral infection – in vitro, thermo- and chemotherapy. Thermotherapy is one of the widely used methods that involves growing and disinfecting vines at temperatures that can delete or inactivate viruses. This method focuses on inactivating viruses rather than completely removing them. Thermotherapy has been tested in the process of obtaining initial healthy grape plants from the grapevine leafroll-associated virus GLRaV-1, GLRaV-2 и GLRaV-3. The objectives of the research are the selection of thermotherapy regimens for the release of grape cuttings from the grapevine leafroll-associated virus (GLRaV-1, GLRaV2 и GLRaV-3). As a result of the research, it was found that the use of thermotherapy of 35 ℃ and 40 ℃ for 20, 30, 40, 50 minutes did not affect the elimination of the grapevine leafroll-associated virus, the yield of diseased plants after treatment was 100 %. A positive result in the healing of plants from the grapevine leafroll-associated virus is achieved at a temperature of 45 ℃ and 50 ℃ (exposure time is 20, 30, 40, 50 minutes). The number of virus-free plants ranges from 45.4 % to 59.8 %. The inclusion of thermotherapy in the process of phytosanitary breeding, as well as in the cultivation of seedlings for mother grape plantations, will significantly increase the guarantee of laying industrial grape plantations with planting material free from phytoplasmic, viral, bacterial and fungal infections. Keywords: grapes, cuttings, grapevine leafroll-associated virus GLRaV-1, GLRaV-2 and GLRaV-3, thermotherapy, thermal stability, elimination, healthy planting material Financing source: The research was carried out within the framework of the Federal project "Development of large-scale scientific and scientific-technological projects in priority research areas" of the national project "Science and Universities"

An Overview on MADS Box Members in Plants: A Meta-Review.

Most of the studied MADS box members are linked to flowering and fruit traits. However, higher volumes of studies on type II of the two types so far suggest that the florigenic effect of the gene members could just be the tip of the iceberg. In the current study, we used a systematic approach to obtain a general overview of the MADS box members' cross-trait and multifactor associations, and their pleiotropic potentials, based on a manually curated local reference database. While doing so, we screened for the co-occurrence of terms of interest within the title or abstract of each reference, with a threshold of three hits. The analysis results showed that our approach can retrieve multi-faceted information on the subject of study (MADS box gene members in the current case), which could otherwise have been skewed depending on the authors' expertise and/or volume of the literature reference base. Overall, our study discusses the roles of MADS box members in association with plant organs and trait-linked factors among plant species. Our assessment showed that plants with most of the MADS box member studies included tomato, apple, and rice after Arabidopsis. Furthermore, based on the degree of their multi-trait associations, FLC, SVP, and SOC1 are suggested to have relatively higher pleiotropic potential among others in plant growth, development, and flowering processes. The approach devised in this study is expected to be applicable for a basic understanding of any study subject of interest, regardless of the depth of prior knowledge.

The single RRM domain-containing protein SARP1 is required for establishment of the separation zone in Arabidopsis.

Abscission is the shedding of plant organs in response to developmental and environmental cues. Abscission involves cell separation between two neighboring cell types, residuum cells (RECs) and secession cells (SECs) in the floral abscission zone (AZ) in Arabidopsis thaliana. However, the regulatory mechanisms behind the spatial determination that governs cell separation are largely unknown. The class I KNOTTED-like homeobox (KNOX) transcription factor BREVIPEDICELLUS (BP) negatively regulates AZ cell size and number in Arabidopsis. To identify new players participating in abscission, we performed a genetic screen by activation tagging a weak complementation line of bp-3. We identified the mutant ebp1 (enhancer of BP1) displaying delayed floral organ abscission. The ebp1 mutant showed a concaved surface in SECs and abnormally stacked cells on the top of RECs, in contrast to the precisely separated surface in the wild-type. Molecular and histological analyses revealed that the transcriptional programming during cell differentiation in the AZ is compromised in ebp1. The SECs of ebp1 have acquired REC-like properties, including cuticle formation and superoxide production. We show that SEPARATION AFFECTING RNA-BINDING PROTEIN1 (SARP1) is upregulated in ebp1 and plays a role in the establishment of the cell separation layer during floral organ abscission in Arabidopsis.

Carbon Nanodot-Microbe-Plant Nexus in Agroecosystem and Antimicrobial Applications.

The intensive applications of nanomaterials in the agroecosystem led to the creation of several environmental problems. More efforts are needed to discover new insights in the nanomaterial-microbe-plant nexus. This relationship has several dimensions, which may include the transport of nanomaterials to different plant organs, the nanotoxicity to soil microbes and plants, and different possible regulations. This review focuses on the challenges and prospects of the nanomaterial-microbe-plant nexus under agroecosystem conditions. The previous nano-forms were selected in this study because of the rare, published articles on such nanomaterials. Under the study's nexus, more insights on the carbon nanodot-microbe-plant nexus were discussed along with the role of the new frontier in nano-tellurium-microbe nexus. Transport of nanomaterials to different plant organs under possible applications, and translocation of these nanoparticles besides their expected nanotoxicity to soil microbes will be also reported in the current study. Nanotoxicity to soil microbes and plants was investigated by taking account of morpho-physiological, molecular, and biochemical concerns. This study highlights the regulations of nanotoxicity with a focus on risk and challenges at the ecological level and their risks to human health, along with the scientific and organizational levels. This study opens many windows in such studies nexus which are needed in the near future.

A Machine Learning Approach to Evaluating the Impact of Natural Oils on Alzheimer’s Disease Progression

Alzheimer’s Disease is among the major chronic neurodegenerative diseases that affects more than 50 million people worldwide. This disease irreversibly destroys memory, cognition, and the overall daily activities which occur mainly among the elderly. Few drugs are approved for Alzheimer’s Disease management despite its high prevalence. To date, the available drugs in the market cannot reverse the damage of neurons caused by the disease leading to the exacerbation of symptoms and possibly death. Medicinal plants are considered a rich source of chemical constituents and have been contributing to modern drug discovery in many therapeutic areas including cancer, infectious, cardiovascular, neurodegenerative and Central Nervous System (CNS) diseases. Moreover, essential oils that are extracted from plant organs have been reported for a wide array of biological activities, and their roles as antioxidants, antiaging, cytotoxic, anti-inflammatory, antimicrobial, and enzyme inhibitory activities. This article highlights the promising potential of plants’ essential oils in the discovery of novel therapeutic options for Alzheimer’s Disease and halting its progression. In this article, 428 compounds were reported from the essential oils isolated from 21 plants. A comparative study is carried out by employing a variety of machine learning techniques, validation, and evaluation metrics, to predict essential oils’ efficacy against Alzheimer’s Disease progression. Extensive experiments on essential oil data suggest that a prediction accuracy of up to 82% can be achieved given the proper data preprocessing, feature selection, and model configuration steps. This study underscores the potential of integrating machine learning with natural product research to prioritize and expedite the identification of bioactive essential oils that could lead to effective therapeutic interventions for Alzheimer’s Disease. Further exploration and optimization of machine learning techniques could provide a robust platform for drug discovery and development, facilitating faster and more efficient screening of potential treatments.

Snowpack permanence shapes the growth and dynamic of non-structural carbohydrates in Juniperus communis in alpine tundra

Climate warming is altering snowpack permanence in alpine tundra, modifying shrub growth and distribution. Plant acclimation to snowpack changes depends on the capability to guarantee growth and carbon storage, suggesting that the content of non-structural carbohydrates (NSC) in plant organs can be a key trait to depict the plant response under different snow regimes.To test this hypothesis, we designed a 3-years long manipulative experiment aimed at evaluating the effect of snow melt timing (i.e., early, control, and late) on NSC content in needles, bark and wood of Juniperus communis L. growing at high elevation in the Alps.Starch evidenced a general decrease from late spring to summer in control and early melting, while starch was low but stable in plants subjected to a late snow melt. Leaves, bark and wood have different level of soluble NSC changing during growing season: in bark, sugars content decreased significantly in late summer, while there was no seasonal effect in needles and wood. Soluble NSC and starch were differently related with the plant growth, when considering different tissues and snow treatment. In leaf and bark we observed a starch depletion in control and early melting plants, consistently to a higher growth (i.e., twig elongation), while in late snow melt, we did not find any significant relationship between growth and NSC concentration.Our findings confirmed that snowpack duration affects the onset of the growing season promoting a change in carbon allocation in plant organs and, between bark and wood in twigs. Finally, our results suggest that plants, at this elevation, could take advantage from an early snow melt caused by climate warming, most likely due to photosynthetic activity by maintaining the level of reserves and enhancing the carbon investment for growth.

Neighbourhood benthic configuration reveals hidden co-occurrence social diversity.

Ecological interactions among benthic communities are crucial for shaping marine ecosystems. Understanding these interactions is essential for predicting how ecosystems will respond to environmental changes, invasive species, and conservation management. However, determining the prevalence of species interactions at the community scale is challenging. To overcome this challenge, we employ tools from social network analysis, specifically exponential random graph modelling (ERGM). Our approach explores the relationships among animal and plant organisms within their neighbourhoods. Inspired by companion planting in agriculture, we use spatiotemporal co-occurrence as a measure of mixed species interaction. In other words, the variety of community interactions based on co-occurrence defines what we call 'co-occurrence social diversity'. Our objective is to use ERGM to quantify the proportion of interactions at both the simple paired level and the more complex triangle level, enabling us to measure and compare co-occurrence social diversity. Applying our approach to the Spanish coastal zone across eight sites, five depths, and sunlit/shaded aspects, we discover that 80% of sessile communities, consisting of over a hundred species, exhibit co-occurrence social diversity, with 5% of species consistently forming associations with other species. These organism-level interactions probably have a significant impact on the overall character of the site. This article is part of the theme issue 'Connected interactions: enriching food web research by spatial and social interactions'.

Comprehensive metabolome characterization of leaves, internodes, and aerial roots of Vanilla planifolia by untargeted LC-MS and GC × GC-MS.

Untargeted metabolomics is a powerful tool that provides strategies for gaining a systematic understanding of quantitative changes in the levels of metabolites, especially when combining different metabolomic platforms. Vanilla is one of the world's most popular flavors originating from cured pods of the orchid Vanilla planifolia. However, only a few studies have investigated the metabolome of V. planifolia, and no LC-MS or GC-MS metabolomics studies with respect to leaves have been performed. The aim of the study was to comprehensively characterize the metabolome of different organs (leaves, internodes, and aerial roots) of V. planifolia. Characterization of the metabolome was achieved using two complementary platforms (GC × GC-MS, LC-QToF-MS), and metabolite identification was based on a comparison with in-house databases or curated external spectral libraries. In total, 127 metabolites could be identified with high certainty (confidence level 1 or 2) including sugars, amino acids, fatty acids, organic acids, and amines/amides but also secondary metabolites such as vanillin-related metabolites, flavonoids, and terpenoids. Ninty-eight metabolites showed significantly different intensities between the plant organs. Most strikingly, aglycons of flavonoids and vanillin-related metabolites were elevated in aerial roots, whereas its O-glycoside forms tended to be higher in leaves and/or internodes. This suggests that the more bioactive aglycones may accumulate where preferably needed, e.g. for defense against pathogens. The results derived from the study substantially expand the knowledge regarding the vanilla metabolome forming a valuable basis for more targeted investigations in future studies, e.g. towards an optimization of vanilla plant cultivation.

Advances in CircRNAs in the Past Decade: Review of CircRNAs Biogenesis, Regulatory Mechanisms, and Functions in Plants.

Circular RNA (circRNA) is a type of non-coding RNA with multiple biological functions. Whole circRNA genomes in plants have been identified, and circRNAs have been demonstrated to be widely present and highly expressed in various plant tissues and organs. CircRNAs are highly stable and conserved in plants, and exhibit tissue specificity and developmental stage specificity. CircRNAs often interact with other biomolecules, such as miRNAs and proteins, thereby regulating gene expression, interfering with gene function, and affecting plant growth and development or response to environmental stress. CircRNAs are less studied in plants than in animals, and their regulatory mechanisms of biogenesis and molecular functions are not fully understood. A variety of circRNAs in plants are involved in regulating growth and development and responding to environmental stress. This review focuses on the biogenesis and regulatory mechanisms of circRNAs, as well as their biological functions during growth, development, and stress responses in plants, including a discussion of plant circRNA research prospects. Understanding the generation and regulatory mechanisms of circRNAs is a challenging but important topic in the field of circRNAs in plants, as it can provide insights into plant life activities and their response mechanisms to biotic or abiotic stresses as well as new strategies for plant molecular breeding and pest control.

Intensification of Rindera graeca transgenic roots proliferation and deoxyshikonin secretion in wave-agitated disposable bioreactor

For millennia, plants have been a source of natural medicines used by humankind. In vitro cultures of plant organs, e.g., transgenic roots, provide a suitable environment for maintaining plant biomass and continuously producing plant-derived bioproducts. The in vitro cultures of plant biomass can be efficiently scaled up using disposable bioreactors with wave-type agitation conditions. The study aimed to investigate the influence of wave-type agitation conditions supported by the WAVE 25 bioreactor on biomass proliferation and secondary metabolite production offered by the in vitro system of Rindera graeca transgenic root culture. Two morphologically different pellets of R. graeca biomass have been observed: highly ramified for cultures performed at ReL < 4000 and compacted for cultures performed at ReL > 5200. The growth of transgenic root biomass cultured in the WAVE 25 bioreactor at ReL = 1325 was over two times higher than for cultures performed in small-scale systems of oscillatory shaken Erlenmeyer flasks.