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Summary: Arsenic poses a global threat to living organisms, compromising crop security and yield. Limited understanding of the transcriptional network integrating arsenic‐tolerance mechanisms with plant developmental responses hinders the development of strategies against this toxic metalloid.Here, we conducted a high‐throughput yeast one‐hybrid assay using as baits the promoter region from the arsenic‐inducible genes ARQ1 and ASK18 from Arabidopsis thaliana, coupled with a transcriptomic analysis, to uncover novel transcriptional regulators of the arsenic response.We identified the GLABRA2 (GL2) transcription factor as a novel regulator of arsenic tolerance, revealing a wider regulatory role beyond its established function as a repressor of root hair formation. Furthermore, we found that ANTHOCYANINLESS2 (ANL2), a GL2 subfamily member, acts redundantly with this transcription factor in the regulation of arsenic signaling. Both transcription factors act as repressors of arsenic response. gl2 and anl2 mutants exhibit enhanced tolerance and reduced arsenic accumulation. Transcriptional analysis in the gl2 mutant unveils potential regulators of arsenic tolerance.These findings highlight GL2 and ANL2 as novel integrators of the arsenic response with developmental outcomes, offering insights for developing safer crops with reduced arsenic content and increased tolerance to this hazardous metalloid. [ABSTRACT FROM AUTHOR]

Background: The extract from Metasequoia glyptostroboides Hu et Cheng, a rare and endangered species native to China, exhibits numerous biological and pharmacological activities. The species is recalcitrant to rooting during micropropagation, a challenge that has yet to be resolved. In this study, transcriptomic and hormonal analyses were conducted to appreciate the molecular mechanism of adventitious root (AR) formation in optimized rooting conditions. Results: The use of 2/5-strength Woody Plant Medium (WPM) significantly promoted AR formation of M. glyptostroboides shoots while the content of endogenous auxin, cytokinins and gibberellins (GAs) varied at different stages of AR formation. Transcriptomic analysis showed the significant up- or down-regulation of differentially expressed genes (DEGs) associated with plant hormone signal transduction and the phenylpropanoid biosynthesis pathway in response to 2/5-strength WPM. DEGs related to the biosynthesis of indole-3-acetic acid, cytokinins and GAs were identified. Transcript factors involved in 13 families were also revealed. A weighted gene co-expression network analysis indicated a strong correlation between hormones and genes involved in plant hormone signal transduction and the phenylpropanoid biosynthetic pathway. Conclusions: These results indicate that the AR-promoting potential of 2/5-strength WPM in M. glyptostroboides was due to complex interactions between hormones and the expression of genes related to plant hormone signal transduction and the phenylpropanoid biosynthetic pathway. [ABSTRACT FROM AUTHOR]

The root system of a plant is essential for plant growth and development because it absorbs nutrients and water from the soil. The root stem cells are maintained and replenished by the quiescent center and are essential for the formation of the specific root structure. In Arabidopsis , the WUSCHEL-RELATED HOMEOBOX 5 (WOX5) plays a key role in regulating root stem cell fate. However, which factor can directly modulate the stability of WOX5 protein remains totally unknown. Here, we report that the peptidase DA1 (LARGE IN CHINESE) interacts with and cleaves WOX5, resulting in the destabilization of WOX5. Genetic analyses support that DA1 acts through WOX5 to regulate root stem cell function. We further demonstrate that cytokinin (CK) signaling induces the accumulation of DA1 protein, thereby decreasing the abundance of WOX5 protein in the root. Consistent with these results, the mutation in DA1 increases the layers of columella stem cells and influences CK-induced differentiation of columella stem cells. Thus, our results reveal a previously unrecognized mechanism by which the cleavage of WOX5 by DA1 connects CK signaling and root stem cell function in Arabidopsis. [Display omitted] • DA1 interacts with and cleaves WOX5, resulting in the destabilization of WOX5 • DA1 acts through WOX5 to regulate root stem cell function • Cytokinin signaling induces the accumulation of DA1 protein • The cleavage of WOX5 by DA1 connects cytokinin signaling and root stem cell function The transcription factor WOX5 plays a key role in regulating root stem cell fate. Cui et al. find that the peptidase DA1 regulates root stem cell function by interacting with and cleaving WOX5. They further demonstrate that the cleavage of WOX5 by DA1 connects cytokinin signaling and root stem cell function in Arabidopsis. [ABSTRACT FROM AUTHOR]

Bioenergy sorghum's large and deep nodal root system and associated microbiome enables uptake of water and nutrients from and deposition of soil organic carbon into soil profiles, key contributors to the crop's resilience and sustainability. The goal of this study was to increase our understanding of bioenergy sorghum nodal root bud development. Sorghum nodal root bud initiation was first observed on the stem node of the 7th phytomer below the shoot apex. Buds were initiated near the upper end of the stem node pulvinus on the side of the stem opposite the tiller bud, then additional buds were added over the next 6-8 days forming a ring of 10-15 nascent nodal root buds around the stem. Later in plant development, a second ring of nodal root buds began forming on the 17th stem node immediately above the first ring of buds. Overall, nodal root bud development can take ~40 days from initiation to onset of nodal root outgrowth. Nodal root buds were initiated in close association with vascular bundles in the rind of the pulvinus. Stem tissue forming nascent nodal root buds expressed sorghum homologs of genes associated with root initiation (WOX4), auxin transport (LAX2, PIN4), meristem activation (NGAL2), and genes involved in cell proliferation. Expression of WOX11 and WOX5 , genes involved in root stem niche formation, increased early in nodal root bud development followed by genes encoding PLTs, LBDs (LBD29), LRP1, SMB, RGF1 and root cap LEAs later in development. A nodal root bud gene regulatory network module expressed during nodal root bud initiation predicted connections linking PFA5 , SPL9 and WOX4 to genes involved in hormone signaling, meristem activation, and cell proliferation. A network module expressed later in development predicted connections among SOMBRERO , a gene involved in root cap formation, and GATA19 , BBM , LBD29 and RITF1 /RGF1 signaling. Overall, this study provides a detailed description of bioenergy sorghum nodal root bud development and transcriptome information useful for understanding the regulation of sorghum nodal root bud formation and development. [ABSTRACT FROM AUTHOR]

Root cap cuticles (RCCs), comprising mainly very-long-chain fatty acids (VLCFAs), promote salt tolerance by preventing ion influx. Glycosylphosphatidylinositol-anchored lipid transfer protein (LTPG)1 and LTPG2 participate in VLCFA deposition in the extracellular region, aiding RCC formation in the lateral roots. In this study, we investigated whether LTPG1 and LTPG2 have similar functions in the primary roots of young Arabidopsis thaliana. Phenotypic analyses, fluorescence microscopy, and quantitative real-time reverse transcription polymerase chain reaction confirmed that NaCl exposure induced LTPG1 and LTPG2 expression and promoted RCC formation in young primary roots. The loss of RCC in the ltpg1 and ltpg2 mutants resulted in increased NaCl sensitivity of root elongation. NaCl also upregulated the expression of several NaCl-responsive genes in ltpg1 and ltpg2. We conclude that RCC formation via LTPG function is pivotal in enhancing salt tolerance in young primary roots. [ABSTRACT FROM AUTHOR]

SUMMARY: The formation and development of storage roots is the most important physiological process in sweetpotato production. Sucrose transporters (SUTs) regulate sucrose transport from source to sink organs and play important roles in growth and development of plants. However, whether SUTs involved in sweetpotato storage roots formation is so far unknown. In this study, we show that IbSUT1, a SUT, is localized to the plasma membrane. Overexpression of IbSUT1 in sweetpotato promotes the sucrose efflux rate from leaves, leading to increased sucrose levels in roots, thus induces lignin deposition in the stele, which inhibits the storage roots formation and compromises the yield. Heterologous expression of IbSUT1 in Arabidopsis significantly increases the sucrose accumulation and promotes lignification in the inflorescence stems. RNA‐seq and biochemical analysis further demonstrated that IbMYB1 negatively regulates the expression of IbSUT1. Overexpression of IbMYB1 in Arabidopsis reduces the sucrose accumulation and lignification degree in the inflorescence stems. Moreover, co‐overexpression of IbMYB1 and IbSUT1 restores the phenotype of lignin over‐deposition in Arabidopsis. Collectively, our results reveal that IbSUT1 regulates source‐sink sucrose transport and participates in the formation of sweetpotato storage roots and highlight the potential application of IbSUT1 in improving sweetpotato yield in the future. Significance Statement: The formation and development of storage roots is the most important physiological process in sweetpotato production. IbSUT1 plays a crucial role in the formation of storage roots by regulating sucrose transport to affect lignin biosynthesis in roots, which provides valuable information for understanding the mechanisms underlying sweetpotato root development and may have implications for the improvement of sweetpotato yields. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H2O2) is naturally produced by plant cells during normal development and serves as a messenger that regulates cell metabolism. Despite its importance, the relationship between hydrogen peroxide and the target of rapamycin (TOR) pathway, as well as its impact on cell division, has been poorly analyzed. In this study, we explore the interaction of H2O2 with TOR, a serine/threonine protein kinase that plays a central role in controlling cell growth, size, and metabolism in Arabidopsis thaliana. By applying two concentrations of H2O2 exogenously (0.5 and 1 mM), we could correlate developmental traits, such as primary root growth, lateral root formation, and fresh weight, with the expression of the cell cycle gene CYCB1;1, as well as TOR expression. When assessing the expression of the ribosome biogenesis-related gene RPS27B, an increase of 94.34% was noted following exposure to 1 mM H2O2 treatment. This increase was suppressed by the TOR inhibitor torin 2. The elimination of H2O2 accumulation with ascorbic acid (AA) resulted in decreased cell division as well as TOR expression. The potential molecular mechanisms associated with the effects of H2O2 on the cell cycle and TOR expression in roots are discussed in the context of the results. [ABSTRACT FROM AUTHOR]

The sugar transporter (STP) gene family is a key regulator of plant development, which is crucial for the efficient transport and utilization of sugars during plant growth and development. In this study, we identified the MeSTP7 gene, which is highly expressed in cassava fibrous roots, early storage roots, and under hormonal treatment, including IAA, MeJA, ABA, and GA3, and abiotic stressors, such as mannitol and NaCl. A strong response was observed with exoqenous IAA. Transfecting MeSTP7 into Arabidopsis promoted early seedling growth, particularly in lateral root development. The content of endogenous hormones (IAA and MeJA) as well as soluble sugars (sucrose, fructose, and glucose) was elevated in transgenic Arabidopsis. Hormone treatments with IAA, MeJA, GA3, and ABA on transgenic Arabidopsis revealed that transgenic Arabidopsis responded positively to added 20 μM IAA. They also exhibited co-induced regulation of lateral root formation by GA3, MeJA, and ABA. qRT-PCR analysis showed that overexpression of MeSTP7 upregulated the expression of IAA14, ARF7, and ARF19 in Arabidopsis. Under IAA treatment, the expression of these genes was similarly upregulated but downregulated under MeJA treatment. These results suggest that MeSTP7 may promote Arabidopsis seedling development by increasing the content of sucrose, glucose, and fructose in roots, which in turn influences IAA-based hormonal signaling. [ABSTRACT FROM AUTHOR]

Background: Continuously growing teeth are an important innovation in mammalian evolution, yet genetic regulation of continuous growth by stem cells remains incompletely understood. Dental stem cells responsible for tooth crown growth are lost at the onset of tooth root formation. Genetic signaling that initiates this loss is difficult to study with the ever-growing incisor and rooted molars of mice, the most common mammalian dental model species, because signals for root formation overlap with signals that pattern tooth size and shape (i.e., cusp patterns). Bank and prairie voles (Cricetidae, Rodentia, Glires) have evolved rooted and unrooted molars while retaining similar size and shape, providing alternative models for studying roots. Results: We assembled a de novo genome of Myodes glareolus, a vole with high-crowned, rooted molars, and performed genomic and transcriptomic analyses in a broad phylogenetic context of Glires (rodents and lagomorphs) to assess differential selection and evolution in tooth forming genes. Bulk transcriptomics comparisons of embryonic molar development between bank voles and mice demonstrated overall conservation of gene expression levels, with species-specific differences corresponding to the accelerated and more extensive patterning of the vole molar. We leverage convergent evolution of unrooted molars across the clade to examine changes that may underlie the evolution of unrooted molars. We identified 15 dental genes with changing synteny relationships and six dental genes undergoing positive selection across Glires, two of which were undergoing positive selection in species with unrooted molars, Dspp and Aqp1. Decreased expression of both genes in prairie voles with unrooted molars compared to bank voles supports the presence of positive selection and may underlie differences in root formation. Conclusions: Our results support ongoing evolution of dental genes across Glires and identify candidate genes for mechanistic studies of root formation. Comparative research using the bank vole as a model species can reveal the complex evolutionary background of convergent evolution for ever-growing molars. [ABSTRACT FROM AUTHOR]

ABSTRACT Soybean (Glycine max) is an important crop for its nutritional value. Its wild relative, Glycine soja, provides a valuable genetic resource for improving soybean productivity. Root development and differentiation are essential for soybean plants to take up water and nutrients, store energy and anchor themselves. Long noncoding RNAs (lncRNAs) have been reported to play critical roles in various biological processes. However, the spatiotemporal landscape of lncRNAs during early root development and differentiation in soybeans is scarcely characterized. Using RNA sequencing and transcriptome assembly, we identified 1578 lncRNAs in G. max and 1454 in G. soja, spanning various root portions and time points. Differential expression analysis revealed 82 and 69 lncRNAs exhibiting spatiotemporally differential expression patterns in G. max and G. soja, respectively, indicating their involvement in the early stage of root architecture formation. By elucidating multiple competitive endogenous RNA (ceRNA) networks involving lncRNAs, microRNAs and protein‐coding RNAs, we unveiled intricate regulatory mechanisms of lncRNA in early root development and differentiation. Our efforts significantly expand the transcriptome annotations of soybeans, unravel the dynamic landscapes of lncRNAs during early root development and differentiation, and provide valuable resources into the field of soybean root research. [ABSTRACT FROM AUTHOR]

Highlights: Urban trees in urban environments are commonly exposed to stresses, contributing to their health decline; Ectomycorrhizal fungi improve the vigour and resilience of Tilia seedlings, but their performance is dependent on soil pH. Inoculation promotes growth in height, biomass production, mycorrhization status, nutrient uptake, and proline accumulation, and these effects dependent on fungi species and soil pH; Inoculation with EcM can be a strategy to produce healthier saplings that when transplanted to the urban environment will have a better performance. Colonization by Ectomycorrhizal (EcM) fungi is key for the health and performance of plants under different stress scenarios, such as those faced by trees in urban environments. Because urban environments can be lacking EcM fungi, we here assessed the benefits of inoculating Tilia tomentosa seedlings in a pre-transplantation nursery context with the EcM fungi Lactarius deliciosus and Paxillus involutus, using substrates of different pH and facing water-stress. P. involutus had a more evident positive effect in T. tomentosa seedlings and had a good performance in both acidic and alkaline substrate. In acidic substrate the fungus increased the plant height by 0.91-fold, increased the mycorrhization rate by 3.23-fold, expansion rate by 5.03-fold and formation of secondary roots by 0.46-fold, compared to the non-inoculated control. This species also improved the phosphorus content of leaves, which revealed a promotion of nutrient uptake. In alkaline substrate P. involutus increased root dry weight by 3.92-fold and the mycorrhization parameters. In contrast, L. deliciosus only had a positive effect in the improvement of mycorrhization and expansion rates and phosphorus content in the root, effects visible only in alkaline substrate. When exposed to water-stress the increase of proline content was visible in acidic substrate for both fungi, L. deliciosus and P. involutus, and in alkaline substrate for the fungus P. involutus, a response indicative of the enhancement of defenses in stressing scenarios such as water scarcity. We conclude that fungal inoculation improves the vigour and resilience of Tilia seedlings and that it is of utmost importance to select a suitable EcM fungus and to consider the soil pH of the transplanting site. The inoculation approach can be a valuable tool to produce robust seedlings which may have a better performance when transplanted to the challenging urban environment. [ABSTRACT FROM AUTHOR]

Developmental reprogramming allows for flexibility in growth and adaptation to changing environmental conditions. In plants, wounding events can result in new stem cell niches and lateral organs. Adventitious roots develop from aerial parts of the plant and are regulated by multiple stimuli, including wounding. Here, we find that Arabidopsis thaliana seedlings wounded at the hypocotyl-root junction reprogram certain pericycle cells to produce adventitious roots proximal to the wound site. We have determined that competence for this reprogramming is controlled; basal cells close to the wound site can produce adventitious roots, whereas cells distal from the wound site mostly cannot. We found that altering cytokinin response or indole-3-butyric acid (IBA)-to-(indole-3-acetic acid) IAA conversion resulted in an expanded adventitious root competence zone and delineated the connection between these pathways. Our work highlights the importance of endogenous IBA-derived auxin and its interaction with cytokinin in adventitious root formation and the regenerative properties of plants. [Display omitted] • Excision-induced adventitious roots (ARs) form proximal to the wound site • Endogenous IBA-derived auxin promotes AR formation • IBA-derived auxin regulates the zone of AR formation • Cytokinin regulates IBA-derived auxin to control the AR competence zone Damodaran and Strader determine that, in Arabidopsis, adventitious roots created in response to wounding occur proximal to the wound site, suggesting that the wound site sets a zone of competence for cellular reprogramming. Cytokinin and IBA-derived auxin dictate this competence zone. [ABSTRACT FROM AUTHOR]

Root growth, nutrient uptake, and nutrient use efficiency of a plant is influenced by the nutrient availability in its growing environment. The aim of this study was to investigate the root morphology, nutrient uptake and use efficiency of Grevillea robusta grown in nitrogen (N)- and phosphorus (P)-limited conditions. A hydroponic experiment was conducted for three months in a glasshouse with four nutrient treatments; (i) N-deficient, (ii) P-deficient, (iii) N/P-deficient (co-limitation of N and P), and (iv) control (sufficient amounts of N, P, and other nutrients in the growth medium). The composition and the concentration of each nutrient in the control solution were custom-made based on the growth requirement of G. robusta. N and P concentration in nutrient-deficient media were maintained at 2 ppm. The impact of N- or P-deficiency and their co-limitation on cluster root formation, organ-specific dry matter and nutrient accumulation, N and P uptake and their use efficiencies were measured. P-deficient conditions produced the highest number of cluster roots (24 ± 4) which was comparatively lower than those of N- and N/P-deficient conditions indicating that P-deficiency is the primary factor influencing the formation of cluster roots in G. robusta. The use efficiency of N and P in biomass formation was significantly (p < 0.05) enhanced when their uptake was reduced in response to N- and P-limitation. The efficient internal use of P by G. robusta under N- and N/P-deficiency is indicated by the significant increase in P-remobilization efficiency under these nutrient-deficient conditions. [ABSTRACT FROM AUTHOR]

Background: Infective endocarditis (IE) is a severe, life-threatening, and relatively common complication after valve replacement operations, with incidence rates varying between 1.8% and 5.8%, with an in-hospital mortality rate of up to 20%. Common microorganisms are (listed by decreasing incidence) Streptococci, Staphylococcus aureus, Enterococci, bacteria of the HACEK group, and fungi. Treatment of IE is complex, typically involving prolonged courses of antibiotics. However, in cases of aortic prosthetic valve endocarditis, root abscess formation with involvement of the aorto-mitral skeleton is not uncommon and complex surgical intervention is required. One of the notable advancements in surgical management is the use of homografts for aortic root endocarditis. Case Reports: We report the first case series of 8 patients successfully operated on for prosthetic valve endocarditis with extensive aortic root abscess formation in Greece at Onassis Cardiac Surgery Center with the use of aortic homograft. All cases were redo surgeries and had good outcomes. Interestingly, one of the cases had extensive aortic root involvement with abscess formation extending to the aorto-mitral fibrous skeleton, requiring aortic root replacement with homograft, aorto-mitral skeleton reconstruction with bovine pericardium and mitral valve replacement with a mechanical prosthesis. Two other patients required concomitant coronary bypass grafting of the right coronary artery with reversed saphenous vein grafts. Conclusions: Aortic root replacement with aortic homograft is the preferred choice for prosthetic valve endocarditis with aortic root abscess formation. Despite the technical complexity needed for implantation, this option offers a second chance for survival in patients with this challenging condition. [ABSTRACT FROM AUTHOR]

HD-Zip proteins are plant-specific transcription factors known for their diverse functions in regulating plant growth, development, and responses to environmental stresses. Among the Medicago truncatula HD-Zip II genes, MtHB2 has been previously linked to abiotic stress responses. In this study, we conducted a functional characterization of MtHB2 in the regulation of root growth and development. Upon auxin stimulation, expression of MtHB2 was promptly up-regulated. Overexpression of MtHB2 in Arabidopsis thaliana led to reduced primary root growth and inhibited lateral root formation. Interestingly, the transgenic plants expressing MtHB2 exhibited differential responses to three types of auxins (IAA, NAA, and 2,4-D) in terms of root growth and development compared to the wild-type plants. Specifically, primary root growth was less affected, and lateral root formation was enhanced in the transgenic plants when exposed to auxins. This differential response suggests a potential role for MtHB2 in modulating auxin transport and accumulation, as evidenced by the reduced sensitivity of the transgenic plants to the auxin transport inhibitor NPA and lower expression levels of auxin-related reporters such as PIN-FORMED (PIN1)::PIN1-GFP, PIN3::PIN3-GFP, PIN7::PIN7-GFP, and DR5::GFP compared to wild-type plants. Additionally, microarray analysis of the root tissues revealed downregulation of several auxin-responsive genes in transgenic seedlings compared to wild-type plants. These findings collectively indicate that MtHB2 plays a critical regulatory role in root growth and development by modulating auxin accumulation and response in the roots. [ABSTRACT FROM AUTHOR]

Summary: The physiological and ecological adaptions of higher plants are driven by anatomical changes that contribute to the evolution of the climbing habit. This not only makes them able to survive in a dry environment but also supports them to undergo secondary growth and complete their reproduction. Some plants even form aerial roots as a survival strategy. In the present study, the anatomy of both aerial and underground roots and stems in Zanonia indica L. (Cucurbitaceae) is investigated. In young stems, vascular bundles (VB) had sieve elements on the inner margin of the protoxylem elements (i.e., bicollateral VB). In stems as well as aerial and underground roots, the axial elements of the secondary xylem were arranged in radial plates separated by wide medullary rays. Aerial and underground roots shared similar features in having exarch protoxylem and distinct narrow piths. Structurally, the secondary xylem was composed of vessels, tracheids, fibres, axial and ray parenchyma cells while extra-fascicular sieve elements were observed only in stems and aerial roots. The formation of aerial roots is a survival mechanism whose significance is discussed with reference to the available literature. [ABSTRACT FROM AUTHOR]

The study of the reproduction characteristics of roses of the garden class Shrub, the definition of the dependence of the hormonal determination of explant rhizogenesis on the concentrations of phytohormones that are part of the nutrient medium, are relevant and has both scientific and practical interest. This study presents the results of studies of hormonal determination of rhizogenesis in explants of cultivars of roses of the garden class Shrub: Gärtnerfreude, Lavender Dream, Pomponella, Red Cascade, Sommerabend cultivated in vitro on nutrient medium containing growth regulators. It has been established that of the nutrient medium modified by the addition of 0.2-1.0 mg/l α-naphthylacetic acid (α-NAA), the most effective was the medium with the content of α-NAA 0.5 mg/l, the content of macro- and microelements half of the Murashige and Skoog prescriptions, and a decrease in the sucrose content to 2.0%. On this medium, the frequency of rhizogenesis averaged 61.2% for the studied cultivars. Hormonal determination of rhizogenesis and efficiency of root formation in vitro in the Shrub rose regenerants depended on the genotype of the plant: cv. Lavender Dream (66.0%) and cv. Sommerabend (67.0%) had the highest rhizogenesis ability. The use of the universal growth regulator Humifield in combination with 0.5 mg/l α-NAA contributed to an increase in the rooting rate of the studied rose cultivars up to 70.0-86.0%. [ABSTRACT FROM AUTHOR]

During nutrient scarcity, plants can adapt their developmental strategy to maximize their chance of survival. Such plasticity in development is underpinned by hormonal regulation, which mediates the relationship between environmental cues and developmental outputs. In legumes, endosymbiosis with nitrogen-fixing bacteria (rhizobia) is a key adaptation for supplying the plant with nitrogen in the form of ammonium. Rhizobia are housed in lateral root-derived organs termed nodules that maintain an environment conducive to Nitrogenase in these bacteria. Several phytohormones are important for regulating the formation of nodules, with both positive and negative roles proposed for gibberellin (GA). In this study, we determine the cellular location and function of bioactive GA during nodule organogenesis using a genetically encoded second-generation GA biosensor, GIBBERELLIN PERCEPTION SENSOR 2 in Medicago truncatula. We find endogenous bioactive GA accumulates locally at the site of nodule primordia, increasing dramatically in the cortical cell layers, persisting through cell divisions, and maintaining accumulation in the mature nodule meristem. We show, through misexpression of GA-catabolic enzymes that suppress GA accumulation, that GA acts as a positive regulator of nodule growth and development. Furthermore, increasing or decreasing GA through perturbation of biosynthesis gene expression can increase or decrease the size of nodules, respectively. This is unique from lateral root formation, a developmental program that shares common organogenesis regulators. We link GA to a wider gene regulatory program by showing that nodule-identity genes induce and sustain GA accumulation necessary for proper nodule formation. Gibberellin patterning is a key difference between nodule organogenesis and lateral root organogenesis. [ABSTRACT FROM AUTHOR]

Roots play an important role in plant growth, including providing essential mechanical support, water uptake, and nutrient absorption. Nanomaterials play a positive role in improving plant root development, but there is limited knowledge of how nanomaterials affect lateral root (LR) formation. Poly (acrylic) acid coated nanoceria (cerium oxide nanoparticles, PNC) are commonly used to improve plant stress tolerance due to their ability to scavenge reactive oxygen species (ROS). However, its impact on LR formation remains unclear. In this study, we investigated the effects of PNC on LR formation in Arabidopsis thaliana by monitoring ROS levels and Ca2+ distribution in roots. Our results demonstrate that PNC significantly promote LR formation, increasing LR numbers by 26.2%. Compared to controls, PNC-treated Arabidopsis seedlings exhibited reduced H2O2 levels by 18.9% in primary roots (PRs) and 40.6% in LRs, as well as decreased O 2 · − levels by 47.7% in PRs and 88.5% in LRs. When compared with control plants, Ca2+ levels were reduced by 35.7% in PRs and 22.7% in LRs of PNC-treated plants. Overall, these results indicate that PNC could enhance LR development by modulating ROS and Ca2+ levels in roots. In this study, we showed that cerium oxide nanoparticles (PNC) promoted lateral root formation in Arabidopsis thaliana by modulating reactive oxygen species and Ca2+ distribution in both primary and lateral roots. Results indicated that applying PNC to plants have potential to improve the development of root system and thus overall plant growth performance. Adopting nanobiotechnology to stimulate plant root system may be beneficial to sustainable agriculture. [ABSTRACT FROM AUTHOR]

Plants have an amazing ability to adapt to their environment, and this extends beyond biochemical responses and includes developmental changes that help them better exploit resources and survive. The plasticity observed in individual plant morphology is associated with robust developmental pathways that are influenced by environmental factors. However, there is still much to learn about the mechanisms behind the formation of the root system. In Arabidopsis thaliana, the root system displays a hierarchical structure with primary and secondary roots. The process of lateral root (LR) organogenesis involves multiple steps, including LR pre-patterning, LR initiation, LR outgrowth, and LR emergence. The study of root developmental plasticity in Arabidopsis has led to significant progress in understanding the mechanisms governing lateral root formation. The importance of root system architecture lies in its ability to shape the distribution of roots in the soil, which affects the plant's ability to acquire nutrients and water. In Arabidopsis, lateral roots originate from pericycle cells adjacent to the xylem poles known as the xylem-pole-pericycle (XPP). The positioning of LRs along the primary root is underpinned by a repetitive pre-patterning mechanism that establishes primed sites for future lateral root formation. In a subset of primed cells, the memory of a transient priming stimulus leads to the formation of stable pre-branch sites and the establishment of founder cell identity. These founder cells undergo a series of highly organized periclinal and anticlinal cell divisions and expansion to form lateral root primordia. Subsequently, LRP emerges through three overlying cell layers of the primary root, giving rise to fully developed LRs. In addition to LRs Arabidopsis can also develop adventitious lateral roots from the primary root in response to specific stress signals such as wounding or environmental cues. Overall, this review creates an overview of the mechanisms governing root lateral root formation which can be a stepping stone to improved crop yields and a better understanding of plant adaptation to changing environments. [ABSTRACT FROM AUTHOR]

• This is the first report on the in vitro propagation of Coelogyne mossiae Rolfe: an endangered endemic orchid of Western Ghats, India. • Among the eight media used, MS media was efficient for asymbiotic seed germination with protocorm (stage IV) establishment. • NAA was proficient in establishing multiple shoot buds and root initials from protocorm explants. • Significant changes in the anatomical characters and biochemicals revealed the adaptability of hardened plants. Coelogyne mossiae Rolfe, an unexplored taxon given its red-listed status by IUCN was selected for in vitro propagation studies due to its conservational significance. The mature pods harboring viable seeds were subjected to inoculation on eight different nutrient media, revealing full-strength Murashige and Skoog (MS) media as highly efficient for seed germination (96.65 %) and subsequent stages of seedling development. Protocorm explants are used for micropropagation on MS media supplemented with various plant growth regulators (PGRs). α- Naphthaleneacetic acid (NAA) in the concentration of 0.5 mg/L facilitated optimal shoot induction resulting in an average of 2.39 multiple buds and 2.46 cm shoot length while 1.0 mg/L 6-Benzyl amino purine (BAP) augmented cultures provided 2.32 multiple shoot buds with an average 1.92 cm height. Half macro-MS augmented with 0.5 mg/L BAP promoted pseudobulb elongation (0.73 cm) while 0.5 mg/L NAA supported root formation (8.33 roots with an average length of 1.12 cm). The resultant plants were acclimatized in pots containing coco peat and brick pieces, exhibiting a survival rate of 63.23 %. The anatomical characteristics of the hardened plants provided insight into factors conducive to their adaptability. Also, the 3-month-old hardened plants demonstrated significantly greater total photosynthetic pigment (0.4915±0.00 mg g-1), total carbohydrate content (72.33±1.69 mg SSE/g), and total protein content (40.26±0.53 mg BSAE/g) when compared to in vitro plants. These findings underscore the potential of in vitro propagation techniques in the conservation and sustainable utilization of Coelogyne mossiae. [ABSTRACT FROM AUTHOR]

Conventional in vitro propagation using semisolid Murashige and Skoog (MS) culture systems is costly, labor-intensive, and requires substantial space for large-scale plant production. This study investigated the application of a temporary immersion bioreactor (TIB) system for the micropropagation of the banana cultivar Kluai Numwa Pakchong 50, as a promising platform for economical commercial production. The cultivation parameters affecting plantlet multiplication, including plant growth regulator (PGR) use, explant density, and immersion frequency, were examined. Additionally, the ex vitro acclimatization of well-developed in vitro plantlets was also evaluated. Using liquid MS medium supplemented with 7.5 mg/L 6-benzylaminopurine (BAP) in the TIB system yielded significantly better results than the conventional semisolid MS control system, producing more shoots (5.60 shoots/explant) and leaves (2.80 leaves/explant) with longer shoot length (2.19 cm). Optimal conditions in the TIB system included an inoculum density of five explants per culture vessel and an immersion frequency of once every 6 or 8 h for 2 min. For root induction, 0.5 mg/L indole-3-butyric acid (IBA) proved more effective than 1-naphthaleneacetic acid (NAA). After 30 days of ex vitro acclimatization, plantlets regenerated from the TIB system demonstrated high survival rates, vegetative growth performance, and root formation efficiency comparable to those from the semisolid culture system. These findings establish the TIB system as a promising platform for the mass propagation of the Kluai Numwa Pakchong 50 banana. The protocol developed in this study could potentially be adapted for large-scale production of other banana varieties. [ABSTRACT FROM AUTHOR]

The Cysteine‐rich secretory proteins (CRISPS), Antigen 5 (Ag5), and Pathogenesis‐related 1 (PR‐1) protein (CAP) superfamily members are found in multiple eukaryotic organisms, including yeasts, animals, and plants. Although one of the plant CAP family genes, PR‐1 is known to respond to pathogen infection in plants, the functions of other CAP family genes in Arabidopsis remain largely unknown. In this study, we conducted a comprehensive analysis of the similarities, loci, and expression patterns of 22 Arabidopsis CAP genes/proteins, providing a clue to elucidate their molecular functions. According to the promoter‐β‐glucuronidase (GUS) analysis, members of the Arabidopsis CAP family were expressed in various young tissues or organs, such as root and shoot meristems, reproductive tissues, and particularly at the lateral root initiation site before the formation of the lateral root primordium, with distinct expression specificity. In particular, CAP51, CAP52, and CAP53 were specifically expressed in the cortical cells at the lateral root developing regions, suggesting that these genes may function in lateral root development. Thus, the expression patterns of Arabidopsis CAP family genes suggest that CAP family proteins may have certain function in the expressed organs or tissues in Arabidopsis plant. [ABSTRACT FROM AUTHOR]

Uncontrollable side reactions at the metal interface have been identified as the root cause of the formation of a fragile solid electrolyte interphase, leading to irreversible sodium loss in sodium metal batteries. Here, we proposed an interface engineering strategy that employed a carboxyl functionalized cellulose separator to provide strong dipole moments and induce the cleavage of P−F bond to construct a solid electrolyte interphase (SEI) rich in NaF. In addition, we employed nuclear magnetic resonance technology confirmed that the separator with strong dipole moments prevented the reduction of organic solvents by attracting electrons, thereby inhibiting the formation of organic oligomers. SEI with high NaF content and few oligomers is smooth and robust, obviously decreasing the interface impedance of the Na anode. The symmetric Na||Na cells, equipped with the functionalized separator, efficiently operated for 1400 hours with a stable 72 mV overpotential at 0.25 mA cm−2, exhibiting low energy barrier and fast ion transport kinetics. The Na||Na3V2(PO4)3 cell also showed stable cycling performance, with the capacity remaining at 94.83 % of the initial capacity after 1000 cycles at 1C. The proposed separator could control the formation and composition of SEI, paving the way for the development of long‐life sodium metal batteries. [ABSTRACT FROM AUTHOR]

AbstractUltrastructural changes and visual symptoms resulting from nutritional disorders involving boron, manganese, iron, zinc, copper, molybdenum, and nickel depend on the species of the plant, and are unknown in passion fruit plants (Passiflora edulis Sims). A hydroponic experiment evaluated the symptoms of nickel addition and micronutrient deficiency in passion fruit seedlings “BRS Gigante Amarelo” and determined the micronutrient contents in leaf and root tissue, root development, ultrastructural changes (leaf tissue deformations) and dry matter accumulation when visual symptoms were observed. Results showed that the order of manifestation of deficiencies was Fe > Mn > Zn > Cu > Mo > B. Nickel toxicity appeared 40 days after the experiment was started, presenting chlorosis in the new leaves followed by general yellowing and some white parts. Boron omission of resulted in deformations in the leaf limbus and loss of apical dominance, showing deformation of the growth points. Mn omission caused reduction of growth and generalized chlorosis of young leaves with a thick reticulum. Iron omission of resulted in internerval chlorosis with a fine lattice appearance. Omission of zinc and copper resulted in deformation and elongation of the leaves, reducing height and root development. Molybdenum omission caused chlorosis in the older leaves, which was observed to spread over time. Iron was the nutrient that most reflected symptoms of deficiency by the formation of root hairs. The findings of this research suggest that the knowledgement of plant micronutrients status permits an understanding of the physiological responses of passion fruit plants to crop fertilization. [ABSTRACT FROM AUTHOR]

Raffinose mitigates plant heat, drought, and cold stresses; however, whether raffinose contributes to plant waterlogging tolerance is unknown. The maize raffinose synthase mutant zmrafs-1 had seedlings that lack raffinose, generated fewer and shorter adventitious roots, and were more sensitive to waterlogging stress, while overexpression of the raffinose synthase gene, ZmRAFS , increased raffinose content, stimulated adventitious root formation, and enhanced waterlogging tolerance of maize seedlings. Transcriptome analysis of null segregant seedlings compared with zmrafs-1 , particularly when waterlogged, revealed that the expression of genes related to galactose metabolism and the auxin biosynthetic pathway were up-regulated by raffinose. Additionally, indole-3-acetic acid content was significantly decreased in zmrafs-1 seedlings and increased in ZmRAFS -overexpressing seedlings. Inhibition of the hydrolysis of raffinose by 1-deoxygalactonojirimycin decreased the waterlogging tolerance of maize seedlings, the expression of genes encoding proteins related to auxin transport-related genes, and the indole-3-acetic acid level in the seedlings, indicating that the hydrolysis of raffinose is necessary for maize waterlogging tolerance. These data demonstrate that raffinose catabolism stimulates adventitious root formation via the auxin signaling pathway to enhance maize waterlogging tolerance. [ABSTRACT FROM AUTHOR]

The triple response phenotype is characteristic for seedlings treated with the phytohormone ethylene or its direct precursor 1-aminocyclopropane-carboxylic acid, and is often employed to find novel chemical tools to probe ethylene responses. We identified a benzoxazole-urea derivative (B2) partially mimicking ethylene effects in a triple response bioassay. A phenotypic analysis demonstrated that B2 and its closest analogue arinole (ARI) induced phenotypic responses reminiscent of seedlings with elevated levels of auxin, including impaired hook development and inhibition of seedling growth. Specifically, ARI reduced longitudinal cell elongation in roots, while promoting cell division. In contrast to other natural or synthetic auxins, ARI mostly acts as an inducer of adventitious root development, with only limited effects on lateral root development. Quantification of free auxins and auxin biosynthetic precursors as well as auxin-related gene expression demonstrated that ARI boosts global auxin levels. In addition, analyses of auxin reporter lines and mutants, together with pharmacological assays with auxin-related inhibitors, confirmed that ARI effects are facilitated by TRYPTOPHAN AMINOTRANSFERASE1 (TAA1)-mediated auxin synthesis. ARI treatment in an array of species, including Arabidopsis, pea, tomato, poplar, and lavender, resulted in adventitious root formation, which is a desirable trait in both agriculture and horticulture. [ABSTRACT FROM AUTHOR]

ABSTRACT Water and soil nutrients are the vital ingredients of crop production, and their efficient uptake is essentially dependent on root development, majorly regulated by auxin. For a water‐loving crop like rice, how water availability regulates nutrient acquisition, additionally, how ambient nutrient level modulates water uptake, and the role of auxin therein is not well studied. While investigating the cross‐talks among these components, we found water to be essential for auxin re‐distribution in roots and shaping the root architecture. We also found that supplementing rice seedlings with moderate concentrations of mineral nutrients facilitated faster water uptake and greater nutrient enrichment in leaves compared to adequate nutrient supplementation. Additionally, moderate nutrient availability favoured greater stomatal density, stomatal conductance, photosynthesis, transpiration rate and water use efficiency when water was not limiting. Further, auxin supplementation enhanced root formation in rice, while affecting their water uptake ability, photosynthesis and transpiration causing differential mineral‐specific uptake trends. The present study uncovers the existence of an intricate crosstalk among water, nutrients and auxin signalling the knowledge of which will enable optimizing the growth conditions for speed breeding of rice and harnessing the components of auxin signalling to improve water and nutrient use efficiency of rice. [ABSTRACT FROM AUTHOR]

Cynanchum acutum L. (Asclepiadaceae) is a perennial vine weed widespread in the Mediterranean region. In Israel, it is native to areas such as the Golan Heights, Galilee, and the northern Negev. Recently, its range has expanded to the Arava Valley in the southern part of Israel. In this study, we investigate the biology and phenology of C. acutum plants originating from both native and invasive populations. To achieve this, we utilized rhizomes from the invasive area in the southern region characterized by a hyper-arid desert climate (Yahel), and from the northern region characterized by a temperate climate (Gvat). Additionally, we examine chemical-based weed management approaches for controlling C. acutum. Rhizomes collected from the northern region showed higher emergence rates at temperatures between 15-30°C, whereas at 35°C, rhizomes from the southern region exhibited a higher emergence rate. Phenology experiments conducted simultaneously at southern and northern locations revealed that plants from the northern location flowered first at both sites. However, flowering initiation occurred ~20 days earlier on average when plants from both populations were grown at the southern site. Pre-emergence herbicide treatments using indaziflam and pyroxasulfone were effective in inhibiting C. acutum root formation. According to the percentage of emergence, pendimethalin showed higher emergence (93% and 100%) in comparison to indaziflam (10% and 93%) and pyroxasulfone (72% and 70%) (2020 and 2021, respectively). Treatments including the herbicide fluroxypyr, as well as the treatment of glyphosate + saflufenacil + surfactant were highly effective in controlling C. acutum plants. These results offer valuable insights into effective weed management strategies for addressing C. acutum infestations. Moreover, our findings underscore the remarkable plasticity of this species and shed light on how populations originating from diverse habitats may have adapted to distinct environmental conditions. [ABSTRACT FROM AUTHOR]

WOXs are a class of plant-specific transcription factors that play key roles in plant growth and stress responses. However, the mechanism by which WOXs influence adventitious root development in Rosa hybrida remains unclear. In this study, RcWOX gene family in rose was identified and phylogenetically analyzed using bioinformatics analysis. A total of 381 RcWOX gene members were localized on seven chromosomes except of nine members. The main cis-acting elements involved in hormonal, light, developmental, and abiotic stress responses were identified in the promoters of RcWOX genes, suggesting their regulation by these signals. Nine RhWOX genes had significant different expression during rooting process of rose. RhWOX331, RhWOX308, RhWOX318 were positive with the formation of rose roots. RhWOX331 was positively involved in the formation of adventitious root primordia, which gene coding a transcription factor localized in the nucleus. The HOX conserved domain in the protein contributed to the self-activating activity of RhWOX331. We obtained genetically modified Arabidopsis to validate the function of RhWOX331. Overexpression of RhWOX331 gene alleviated the inhibition of root length of A. thaliana primary roots by high concentration of IBA and NPA, and significantly increased the number of lateral roots on the primary roots, as well as the height of A. thaliana plants. Additionally, RhWOX331 promoted adventitious root formation in A. thaliana and mitigated hormonal inhibition by exogenous 6-BA, NPA, and GA3. The RhWOX331 promoter contained cis-acting elements such as ABRE, Box 4 and CGTCA-motif et.al. GUS activity analysis showed that the gene acted at the cotyledon attachment site. Taken together, these studies identified a significant expansion of the RcWOX gene family, inferred roles of certain branch members in adventitious root formation, elucidated the function of RhWOX331 in adventitious root initiation, and laid the foundation for further research on the function of WOX gene family in roses. [ABSTRACT FROM AUTHOR]

Respiratory Burst Oxidase Homologues (RBOHs) are involved in plant growth, development, and stress adaptation. How OsRBOHs affect root hair formation and consequently nutrient acquisition and drought resistance in rice is not well understood. We knocked out six OsRBOH genes in rice that were expressed in roots and identified OsRBOHE as the only one affecting root hair formation. OsRBOHE was strongly expressed in the root epidermis, root hairs and tiller buds. OsRBOHE is localised at the plasma membrane. Knockout of OsRBOHE decreased reactive oxygen species generation in the root hairs and tiller buds, downregulated genes involved in cell wall biogenesis, and decreased root hair length and tillering by 90% and 30%, respectively. Knockout of OsRBOHE decreased phosphorus acquisition only in low available P soil under aerobic conditions, but not in high P soil or under flooded conditions when P was likely not limited by diffusion. Knockout of OsRBOHE markedly decreased drought resistance of rice plants through the effect on root hair formation and the associated rhizosheath. Taken together, OsRBOHE is crucial for root hair formation and tillering and consequently on drought resistance in rice. The contribution of root hairs to P acquisition in rice is limited to aerobic soil. [ABSTRACT FROM AUTHOR]

Propagation of cuttings is the primary method of rose multiplication. Aux/IAA, early response genes to auxin, play an important role in regulating the process of adventitious root formation in plants. However, systematic research on the identification of RhAux/IAA genes and their role in adventitious root formation in roses is lacking. In this study, 34 RhAux/IAA genes were identified by screening the rose genome, distributed on seven chromosomes, and classified into three clades based on the evolutionary tree. An analysis of the cis-acting elements in the promoters of RhAux/IAA genes revealed the presence of numerous elements related to plant hormones, the light signal response, the growth and development of plants, and abiotic stress. RNA-seq analysis identified a key RhIAA25 gene that may play an important role in the generation of adventitious roots in roses. Subcellular localization, yeast self-activation, and tissue-specific expression experiments indicated that RhIAA25 encoded a nuclear protein, had no yeast self-activated activity, and was highly expressed in the stem. The overexpression of RhIAA25 promoted the elongation of the primary root in Arabidopsis but inhibited adventitious root formation. This study systematically identified and analyzed the RhAux/IAA gene family and identified a key gene, RhIAA25, that regulates adventitious root generation in roses. This study offers a valuable genetic resource for investigating the regulatory mechanism of adventitious root formation in roses. [ABSTRACT FROM AUTHOR]

Background/Objectives: Rehmannia glutinosa, a highly valuable medicinal plant in China, is encountering severe replant disease. Replant disease represents a complex stress driven by multiple principal factors (RDFs), including allelochemicals, microbes, and their interactions. miRNAs are recognized as key regulators of plant response to stresses; however, their specific roles within RDFs are not entirely clear. Methods: This study builds six RDF treatments, comprising R. glutinosa continuously planted (SP), normally planted (NP), and NP treated with ferulic acid (FA), Fusarium oxysporum (FO), and a combination of FA with FO (FAFO). sRNA-seq technology was used to identify crucial miRNAs in response to diverse RDFs. Results: In total, 30 sRNA datasets were generated from the SP, NP, FA, FO, and FAFO samples. A total of 160 known and 41 novel miRNAs (RgmiRNAs) were identified in the R. glutinosa genome based on the sRNA database. Abundance analysis revealed that RgmiRNAs in SP exhibited a distinct expression profile in comparison with others. Of these, 124, 86, 86, and 90 RgmiRNAs were differentially expressed in SP, FA, FO, and FAFO compared with NP. Target analysis indicated that RgmiRNAs downregulated in both SP and RDFs impede the organism growth of R. glutinosa. RgmiRNAs upregulated in SP can disrupt root formation and nutrient metabolism, in which, two RgmiR398 were uniquely expressed in SP. It was confirmed to target RgCSD genes. The expression patterns of RgmiR398 and RgCSD indicated that replant disease induces the oxidative damage of R. glutinosa through RgmiR398. Conclusions: RgmiRNA profiling under RDFs provides a theoretical basis for the further clarification of RgmiRNA function in replant disease. [ABSTRACT FROM AUTHOR]

Background: The aim of this case report was to present a translational approach to tooth autotransplantation using jiggling forces to enlarge the periodontal ligament (PDL) space before autotransplantation, with the goal of improving treatment success and long‐term survival. Methods: A 23‐year‐old patient, undergoing orthodontic therapy and with an unrestorable maxillary first molar, was proposed to have a healthy and fully‐erupted maxillary third molar transplanted in the socket of the first molar. Jiggling forces were applied to the third molar to enlarge the PDL space and facilitate the preservation of PDL fibers on the root surfaces during the extraction. Results: Jiggling forces induced hypermobility and widened PDL space of the third molar. The autotransplantation was successful and the patient was followed regularly over a 27‐year period. At the 27‐year visit, the patient showed optimal chewing function, oral plaque control, and absence of gingivitis. The transplanted molar exhibited periodontal health and absence of mobility. Probing depth of 5 mm and radiographic external root resorption was noted on a localized area of the transplanted tooth which had experienced traumatic and unintentional removal of PDL fibers during the extraction. Conclusions: A translational approach was proposed by integrating knowledge from the fields of orthodontics, trauma from occlusion, and replantation. It validated the crucial importance of maintaining healthy PDL fibers on the root surface and demonstrated clinically the successful autotransplantation of a fully formed third molar into the socket of a first molar with a retention of 27 years. Key points: Why is this case new information?This case provided evidence of successful autotransplantation of a molar with complete root formation. It reported the longest‐term follow‐up (27 years) present in the literature. Most importantly, it used a translational medicine approach to apply concepts from the fields of orthodontics and traumatic occlusion to improve the success of the autotransplantation procedure. What are the keys to the successful management of this case?Jiggling forces induced tooth hypermobility and increased the PDL space of the tooth planned for autotransplantation. In turn, they facilitated the atraumatic extraction and preservation of the PDL fibers on the transplanted tooth, improving the success of the reattachment of periodontal fibers. What are the primary limitations to success in this case?Traumatic extraction resulting in the unintended removal of PDL fibers from the tooth planned for autotransplantation, or intentional removal of PDL fibers with root planing are expected to decrease the success rate of the autotransplantation procedure. This is due to the lack of viable PDL cells necessary for reattachment. [ABSTRACT FROM AUTHOR]

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The purpose of the study is to optimize the trophic and hormonal determination of raspberry reproduction in vitro and post-aseptic adaptation ex vitro. The research was carried out on the remontant raspberry variety Delniwa of Polish selection. Laboratory studies were carried out in the conditions of the Tevitta TM laboratory (Ltd "Agrofirm Blagodatne," Cherkasy region), and experiments were laid in four stages: introduction into aseptic culture, multiplication, induction of rhizogenesis, and post-aseptic adaptation, including photoautotrophic grafting. A medium for obtaining an aseptic culture and a media for multiplication have been selected. The rate of regeneration of explants of different origins, and the percentage of regenerants from them, was compared. The dynamics of the influence of cytokinin concentrations during long-term reproduction in vitro were revealed. Cultivation on a medium with a high content of benzylaminopurine and kinetin showed the effect of accumulation of phytotoxicity. The expediency of growing graft donors for grafting at low kinetin concentrations to improve the induction of rhizogenesis is substantiated. Regenerants from media with a predominance of auxins over cytokinins had a higher regeneration potential. According to indicators of suitability for survival, perlite substrates prevailed over peat ones; however, regenerants of a smaller height were formed on them. The symptoms and harmful effects of excessive watering on plants have been established. A biomethod of insect control using insectivorous plants of the genus Drosera has been developed. The rate of rhizogenesis in bioreactor conditions with humidified and carbon dioxide-enriched air significantly exceeded root formation in conventional moist chambers. The duration of growing an adapted and well-rooted seedling in a bioreactor was 21 days, compared to 30 or more days in the control version of the experiment. The plants did not lose turgor when planted in closed soil. Adapted regenerants are successfully used as a planting material and can be used in photoautotrophic microclonal propagation as donors of cuttings. Under such conditions, the regeneration efficiency is maintained for five cutting generations. [ABSTRACT FROM AUTHOR]

The aim of the study is to determine the evapotranspiration by stages of development, with which, in an indirect way, quickly and easily predict and manage the irrigation regime of head celery. A field experiment was conducted with celery in the Plovdiv region, grown under irrigated conditions. There are six options, irrigated with different irrigation rates, are set as follows: option 1) 130%, option 2) 100%, option 3) 70%, option 4) 50% and option 5) 30% of the calculated rate, option 6) without irrigation. In the hypothetical optimal variant, a pre-irrigation humidity of 80% of the FC (field capacity) was maintained in the 0-40 cm layer. The development period is divided into three sub-periods: 1 - from the interception of seedlings to the beginning of root formation; 2 - beginning of growth of the root crop and 3 stage - Intensive growth until harvesting. ETc was established by phases of development for celery, and in the layer 0-0.4m a maximum (3.8 and 4.42) was recorded in phase 2 - the beginning of the formation of the root crop, respectively for the variants irrigated with 100% and 130 % of the norm. With the same options, but at a depth of 0-0.5m ETc is 4.81 and 5mm. In the first phase of development, celery spends about 155 mm in variants 1 and 2, between 110 and 95 in variants 3 and 4 and between 78 and 60 mm in variants 5 and 6. [ABSTRACT FROM AUTHOR]

A three-year field experiment was conducted with celery under irrigated conditions in the Plovdiv region 42° 08‘ 06“ N024° 44‘ 43“ E and 160 m above sea level. The purpose of the development is to establish the biophysical coefficients (Z, R and Ks) of the evapotranspiration of the crop and to recommend the most suitable ones for managing the irrigation regime. The experiment spanned three distinct years, each characterized by varying climatic factors. Throughout all three years, vegetation precipitation was insufficient and unevenly distributed. Post statistical analysis, they were defined as wet, medium and dry. The soil is an alluvial meadow with a bulk density of 1.33 g/cm3 for the 0-0.4m layer where soil moisture was monitored. Real evapotranspiration data of celery, obtained via the weight-thermostat method with regular soil sampling, were used. Three phases of celery development are distinguished, the first being from the interception of seedlings to the beginning of the formation of the root crop, the second - covering the beginning of growth of the root crop and the third phase - from intensive growth to harvest. The Z-factor values by phase were 0.14, 0.21, and 0.24 for R – 0.24, 0.4 and 0.6, and for Kc – 0.65, 1.01 and 1.51. [ABSTRACT FROM AUTHOR]

Populus spp. is an economically valuable tree worldwide, known for its adaptability, fast growth, and versatile wood, often cultivated in short-rotation plantations. Effective propagation is crucial for rapid genetic improvement and global demand for forest products and biomass energy. This study focused on the rooting and growth of poplar cuttings, examining shoot collection timing and growth stimulant treatments across four hybrids: Populus deltoides × P. nigra (Agathe F), P. maximowiczii × P. trichocarpa (Arges), P. deltoides × P. trichocarpa (Donk), and an interspecific hybrid Populus × canadensis (F-448). The experiment used hybrid poplar cuttings collected in spring 2022 and 2023, planted in controlled climates with a randomized block design. Cuttings were soaked for 24 h in growth stimulants, namely indole-3-butyric acid, cinnamic acid, and indole-3-acetic acid. After 12 weeks, rooting percentage and seedling height were assessed. The study found that the optimal time for collecting poplar cuttings for best rooting is late winter to early spring, specifically from March to early April, with shoots collected after early April showing the lowest rooting potential. The growth stimulants significantly influenced the growth of poplar seedlings. There was a tendency for lower concentrations to increase root formation and seedling height, while higher concentrations had adverse effects. Despite variations in growth rates, a consistent growth pattern was observed across different shoot collection dates for all genomic groups. [ABSTRACT FROM AUTHOR]

This article explores the development of adventitious roots in rose cuttings and the factors that contribute to successful root formation. The study uses imaging and spectroscopy techniques to investigate the differences between easy-to-root and hard-to-root rose cultivars. The researchers find that cell wall composition plays a crucial role in the emergence of adventitious roots. The findings highlight the importance of integrated approaches to overcome propagation challenges. The article suggests that a better understanding of the physiology of rooting recalcitrance could lead to more effective propagation strategies. [Extracted from the article]

Adventitious root (AR) formation is one of the most important developmental processes in vegetative propagation. Although genotypic differences in rose rooting ability are well known, the causal factors are not well understood. The rooting of two contrasting genotypes, 'Herzogin Friederike' and 'Mariatheresia', was compared following a multiscale approach. Using magnetic resonance imaging, we non-invasively monitored the inner structure of stem cuttings during initiation and progression of AR formation for the first time. Spatially resolved Fourier-transform infrared spectroscopy characterized the chemical composition of the tissues involved in AR formation. The results were validated through light microscopy and complemented by immunolabelling. The outcome demonstrated similarity of both genotypes in root primordia formation, which did not result in root protrusion through the shoot cortex in the difficult-to-root genotype 'Mariatheresia'. The biochemical composition of the contrasting genotypes highlighted main differences in cell wall-associated components. Further spectroscopic analysis of 15 contrasting rose genotypes confirmed the biochemical differences between easy- and difficult-to-root groups. Collectively, our data indicate that it is not the lack of root primordia limiting AR formation in these rose genotypes, but the firmness of the outer stem tissue and/or cell wall modifications that pose a mechanical barrier and prevent root extension and protrusion. [ABSTRACT FROM AUTHOR]

Exploring plant growth-promoting (PGP) bacterial activity of microbial components aggregated by wastewater treatment can reduce dependence on fossil fuel-derived fertilisers. This study describes the isolation and identification of bacteria from microalgae-bacteria flocs (MaB-flocs) generated in high-rate algal oxidation ponds (HRAOP) of an integrated algal pond system (IAPS) remediating municipal wastewater. Amplified 16S rRNA gene sequence analysis determined the molecular identity of the individual strains. Genetic relatedness to known PGP rhizobacteria in the NCBI GenBank database was by metagenomics. Isolated strains were screened for the production of indoles (measured as indole-3-acetic acid; IAA) and an ability to mineralise ${\rm NH}_4^ +$ NH 4 + , ${\rm PO}_4^{3-}$ PO 4 3 − , and K +. Of the twelve bacterial strains isolated from HRAOP MaB-flocs, four produced indoles, nine mineralised ${\rm NH}_4^ +$ NH 4 + , seven solubilised P, and one K. Potential of isolated strains for PGP activity according to one-way ANOVA on ranks was: ECCN 7b > ECCN 4b > ECCN 6b > ECCN 3b = ECCN 10b > ECCN 1b = ECCN 5b > ECCN 8b > ECCN 2b > ECCN 12b > ECCN 9b = ECCN 11b. Further study revealed that cell-free filtrate from indole-producing cultures of Aeromonas strain ECCN 4b, Enterobacter strain ECCN 7b, and Arthrobacter strain ECCN 6b promoted mung bean adventitious root formation suggestive of the presence of auxin-like biological activity. [ABSTRACT FROM AUTHOR]

Cassava serves as a crucial raw material and sustenance staple in developing countries, extensively used in the production of starch, bioethanol, and various bioproducts. However, the cultivation of cassava is increasingly challenged by diseases, particularly the cassava mosaic virus. Therefore, efficient propagule systems are needed to provide disease‐free plants to sustain production. This study aimed to develop a rapid propagation method to increase the production of planting material. Various propagation media were assessed for their impact on root formation and plantlet vigour using a 3 × 4 factorial in a Randomized Complete Block Design during April 2023 to September 2023. Three cassava cultivars (KU50, RY9, and HB60) were tested against four media (distilled water, 250 mg·L−1 IBA, SAH solution, and IBA + SAH combination). Subsequently, the optimal medium was used to compare three propagation techniques (leaf bud, mini, and normal cutting) across the cassava cultivars. Aeroponic systems were then employed for further shoot multiplication, evaluating growth and survival metrics. In the first experiment, RY9 had better growth parameters, while KU50 had the highest survival rate at 82%. Applying the SAH was the optimal solution when compared to other media tested. It significantly enhanced the plantlet height (7.30 cm), survival percentage (71.61%), plantlet vigour index (1513.60), and allometric coefficient (0.55). The leaf bud technique had the highest multiplication trait values, whereas the mini‐cutting method had the highest survival rate, and normal cutting had superior performance compared to leaf bud and mini‐cutting for the plant growth parameters. Plantlets produced through mini‐cutting (93%) and leaf bud propagation (92%) had a higher survival rate than those produced using normal cutting (46%) in the aeroponic system under greenhouse conditions. The study revealed a homogeneity in growth and survival traits across the cassava cultivars evaluated in aeroponic cultivation. These findings demonstrated the potential of using leaf bud or mini‐cutting propagation techniques for multiplication in aeroponic cultivation to produce high‐quality plantlets on a large‐scale production. [ABSTRACT FROM AUTHOR]

The development of rotary files and other endodontic instrument techniques have revolutionised treatment by enhancing canal preparation and producing rounder, smoother canals that are constructed of Nickel-Titanium (NiTi) alloy. There are two types of movements in these instruments: rotary continuous and reciprocating. Rotary continuous movements involve torsion and flexion, and can cause instrument fractures. An alternative approach to avoid the issue is proposed, which involves reciprocating movement. The present literature review compares the incidence of dentinal crack formation in root canal walls when using stainless steel and NiTi rotary systems. It highlights the potential complications, such as tooth fracture and increased bacterial susceptibility due to contact between instruments and dentinal walls. [ABSTRACT FROM AUTHOR]

Summary: Building sustainable platforms to produce biofuels and specialty chemicals has become an increasingly important strategy to supplement and replace fossil fuels and petrochemical‐derived products. Terpenoids are the most diverse class of natural products that have many commercial roles as specialty chemicals. Poplar is a fast growing, biomassdense bioenergy crop with many species known to produce large amounts of the hemiterpene isoprene, suggesting an inherent capacity to produce significant quantities of other terpenes. Here we aimed to engineer poplar with optimized pathways to produce squalene, a triterpene commonly used in cosmetic oils, a potential biofuel candidate, and the precursor to the further diversified classes of triterpenoids and sterols. The squalene production pathways were either re‐targeted from the cytosol to plastids or co‐produced with lipid droplets in the cytosol. Squalene and lipid droplet co‐production appeared to be toxic, which we hypothesize to be due to disruption of adventitious root formation, suggesting a need for tissue specific production. Plastidial squalene production enabled up to 0.63 mg/g fresh weight in leaf tissue, which also resulted in reductions in isoprene emission and photosynthesis. These results were also studied through a technoeconomic analysis, providing further insight into developing poplar as a production host. [ABSTRACT FROM AUTHOR]

The identification of chemicals that modulate plant development and adaptive responses to stresses has attracted increasing attention for agricultural applications. Recent basic studies have identified functional amino acids that are essential for plant organogenesis, indicating that amino acids can regulate plant growth. In this study, we newly identified 2‐aminopimelic acid (2APA), a nonproteinogenic amino acid, as a novel bioactive compound involved in root morphogenesis. This biological effect was confirmed in several plant species. Our phenotypic analysis revealed that the bioactive 2APA is an l‐form stereoisomer. Overall, our study identified a promising root growth regulator and provided insight into the intricate metabolism related to root morphology. [ABSTRACT FROM AUTHOR]

Plants communicate underground by secreting multiple amino acids (AAs) through their roots, triggering defense mechanisms against cadmium (Cd) stress. However, the specific roles of the individual AAs in Cd translocation and detoxification remain unclear. This study investigated how exogenous AAs influence Cd movement from the roots to the shoots in Cd-resistant and Cd-sensitive Chinese cabbage cultivars (Jingcui 60 and 16-7 cultivars). The results showed that methionine (Met) and cysteine (Cys) reduced Cd concentrations in the shoots of Jingcui 60 by approximately 44% and 52%, and in 16-7 by approximately 43% and 32%, respectively, compared to plants treated with Cd alone. However, threonine (Thr) and aspartic acid (Asp) did not show similar effects. Subcellular Cd distribution analysis revealed that AA supplementation increased Cd uptake in the roots, with Jingcui 60 preferentially storing more Cd in the cell wall, whereas the 16-7 cultivar exhibited higher Cd concentrations in the organelles. Moreover, Met and Cys promoted the formation of Cd-phosphate in the roots of Jingcui 60 and Cd-oxalate in the 16-7 cultivar, respectively. Further analysis showed that exogenous Cys inhibited Cd transport to the xylem by downregulating the expression of HMA2 in the roots of both cultivars, and HMA4 in the 16-7 cultivar. These findings provide insights into the influence of exogenous AAs on Cd partitioning and detoxification in Chinese cabbage plants. [ABSTRACT FROM AUTHOR]

(1) The development of sweet potato storage roots is impacted by nitrogen (N) levels, with excessive nitrogen often impeding development. Starch synthesis enzymes such as sucrose synthase (SUS) and ADP-glucose pyrophosphorylase (AGPase) are pivotal in this context. Although the effects of excessive nitrogen on the formation of sweet potato storage roots are well documented, the specific responses of IbSUSs and IbAGPases have not been extensively reported on. (2) Pot experiments were conducted using the sweet potato cultivar "Pushu 32" at moderate (MN, 120 kg N ha−1) and excessive nitrogen levels (EN, 240 kg N ha−1). (3) Nine IbSUS and nine IbAGPase genes were categorized into three and two distinct subgroups based on phylogenetic analysis. Excessive nitrogen significantly (p < 0.05) suppressed the expression of IbAGPL1, IbAGPL2, IbAGPL4, IbAGPL5, IbAGPL6, IbAGPS1, and IbAGPS2 in fibrous roots and IbSUS2, IbSUS6, IbSUS7, IbSUS8, IbSUS9, IbAGPL2, and IbAGPL4 in storage roots, and then significantly (p < 0.05) decreased the SUS and AGPase activities and starch content of fibrous root and storage root, ultimately reducing the storage root formation of sweet potato. Excessive nitrogen extremely significantly (p < 0.01) enhanced the expression of IbAGPL3, which was strongly negatively correlated with the number and weight of storage roots per plant. (4) IbAGPL3 may be a key gene in the response to excessive nitrogen stress and modifying starch synthesis in sweet potato. [ABSTRACT FROM AUTHOR]

SUMMARY: Legumes have evolved a nitrogen‐fixing symbiotic interaction with rhizobia, and this association helps them to cope with the limited nitrogen conditions in soil. The compatible interaction between the host plant and rhizobia leads to the formation of root nodules, wherein internalization and transition of rhizobia into their symbiotic form, termed bacteroids, occur. Rhizobia in the nodules of the Inverted Repeat‐Lacking Clade legumes, including Medicago truncatula, undergo terminal differentiation, resulting in elongated and endoreduplicated bacteroids. This transition of endocytosed rhizobia is mediated by a large gene family of host‐produced nodule‐specific cysteine‐rich (NCR) peptides in M. truncatula. Few NCRs have been recently found to be essential for complete differentiation and persistence of bacteroids. Here, we show that a M. truncatula symbiotic mutant FN9285, defective in the complete transition of rhizobia, is deficient in a cluster of NCR genes. More specifically, we show that the loss of the duplicated genes NCR086 and NCR314 in the A17 genotype, found in a single copy in Medicago littoralis R108, is responsible for the ineffective symbiotic phenotype of FN9285. The NCR086 and NCR314 gene pair encodes the same mature peptide but their transcriptional activity varies considerably. Nevertheless, both genes can restore the effective symbiosis in FN9285 indicating that their complementation ability does not depend on the strength of their expression activity. The identification of the NCR086/NCR314 peptide, essential for complete bacteroid differentiation, has extended the list of peptides, from a gene family of several hundred members, that are essential for effective nitrogen‐fixing symbiosis in M. truncatula. Significance Statement: Our results demonstrate the requirement of NCR086/NCR314, which are members of the nodule‐specific cysteine‐rich peptide family, for effective symbiotic interaction between Medicago truncatula and the tested rhizobia strains. The NCR086/NCR314 peptides are encoded by a highly similar gene pair in M. truncatula A17 that was duplicated following the separation of lines M. truncatula A17 and Medicago littoralis R108. [ABSTRACT FROM AUTHOR]