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Corn stunt is a vector-transmitted disease that provokes physiological disorders expressed in leaves, stalks, and ears, ultimately resulting in premature plant death. Despite its agronomic importance, the quantitative relationship between corn stunt severity and early plant mortality has not been clearly elucidated. This study fills this gap by examining how incremental corn stunt severity affects the incidence of premature death and how different corn genotypes influence this relationship. Data were collected from three independent experiments conducted at different locations in Brazil, where disease severity and percentage of early plant death were recorded. Using a linear mixed-effect model, we found a significant increase in the probability of premature death with the increase in corn stunt severity. Furthermore, our analysis demonstrated that genetic background plays a central role in this pathosystem, with certain genotypes exhibiting enhanced resistance that mitigates the impact of corn stunt on plant mortality. These results indicate the potential for selective breeding efforts to identify and propagate genotypes that exhibit lower susceptibility to premature death under high disease pressure.

Hop stunt viroid (HSVd) is an emerging threat to sweet cherry production in China, yet its geographic distribution and genomic characteristics remain poorly understood. Here, we report the first occurrence of HSVd in cherry in Hebei Province and the complete genome sequences of three local isolates: YT-HSVd&#x2011;1 (PQ580329), YT-HSVd&#x2011;14 (PQ580330), and YT-HSVd&#x2011;15 (PQ580350). Phylogenetic analysis placed them within a distinct Plum&#x2011;type clade alongside isolates SC&#x2011;17, SC&#x2011;13 (Shandong sweet cherry), FP2 (Japanese plum; AB098502.1), HSVd.apr9, and HSVd.apr10 (Moroccan apricot), sharing 91.45-97.01% nucleotide identity with other known HSVd variants. Additionally, we developed a cherry&#x2011;adapted SYBR Green I&#x2011;based RT&#x2011;qPCR assay using optimized primer sets (HSVd&#x2011;q117F/R and HSVd&#x2011;q168F/R) at 10&#x202f;&#x3bc;mol&#xb7;L&#x207b;&#xb9; with annealing temperatures of 55.0&#x202f;&#x2103; and 56.9&#x202f;&#x2103;, respectively. The assay demonstrated high sensitivity, with detection limits of 12.9 and 1.29 copies&#xb7;&#xb5;L-1 and excellent reproducibility (Ct value CV < 5%). When applied to field samples, HSVd was reliably detected (100% detection rate) across all tested tissues, showing the highest viral titer in branch bark, followed by leaves and fruit stalks, and the lowest in fruit peels. This study provides the first complete HSVd genomes from Hebei Province and establishes a rapid, sensitive detection tool to support future surveillance and etiological research.

Sweet potato chlorotic stunt virus (SPCSV) is a major pathogen that threatens sweet potato production. It frequently acts synergistically with other viruses, causing severe yield losses and quality decline. A rapid and efficient detection method is therefore essential for preventing and controlling the spread of this virus. Here, we developed a reverse transcription real-time fluorescence recombinase-aided amplification (RT-RAA) assay using human apurinic/apyrimidinic endonuclease 1 (hAPE1, designated as tool enzyme E10). This enzyme exhibits high AP endonuclease activity but extremely low exonuclease activity, so that amplification products remain intact rather than being degraded as commonly occurs with the traditionally used Exonuclease III (ExoIII), thereby preserving product integrity for subsequent analysis. The established RT-hAPE1-RAA assay for SPCSV can be completed within 10 minutes and has a sensitivity of 100 ag/&#x3bc;L, corresponding to approximately 26 copies/&#x3bc;L of a recombinant pUC57 plasmid (3,484 bp) containing a 774bp SPCSV coat protein gene. Gel electrophoresis confirmed that E10 preserved viral amplification fragments intact, whereas ExoIII caused significant degradation. When testing 43 field-collected sweet potato samples, the method demonstrated a sensitivity of 94.4% and a specificity of 100%, showing high concordance with RT-qPCR results . Furthermore, E10 maintained stable cleavage activity across diverse target sequences, indicating its broad applicability. This work provides a rapid, sensitive, and reliable tool for SPCSV detection and offers technical support for the on-site diagnosis of sweet potato viral diseases.

Radial collateral ligament injuries of the thumb are rare, especially in adolescent athletes. We present a case of a 17-year-old female cheerleader who sustained a complete radial collateral ligament tear while basing during a cheerleading stunt. The patient presented to the emergency department with pain in the right thumb after catching a falling flyer. Examination of the first metacarpophalangeal joint of the right thumb revealed tenderness and laxity. Radiographic imaging showed no fracture. Magnetic resonance imaging confirmed a complete radial collateral ligament tear. She underwent surgical repair with full recovery. This case highlights an uncommon thumb ligament injury in a non-traditional mechanism. Emergency physicians should consider radial collateral ligament tears in patients with metacarpophalangeal joint tenderness, even when radiographs are normal.

Citrus yellow vein clearing virus (CYVCV) is the causative agent of the yellow vein clearing disease (YVCD), a worldwide and highly destructive disease in lemon (Citrus lemon) and sour orange trees (C. aurantium). The typical symptoms of vein clearing are believed to be associated with CYVCV infection in citrus, so virus-specific diagnostic systems are currently used to confirm infection. In the present study, virome analysis based on high-throughput sequencing (HTS) on a lemon plant showing YVCD revealed mixed infection of CYVCV, iris domestica betaflexyviridae 1 (IDBV), and hop stunt viroid (HSVd). This multiple infection was confirmed in other two lemon plants with similar symptoms using virus/viroid specific primers. This is the first report of IDBV in lemon. Through molecular characterization and the reconstruction of phylogenetic relationships, a possible origin of the viruses/viroid identified in lemon has been hypothesized. Such mixed infections raise new questions about their role in the expression of YVCD symptoms observed on lemon.

Sweet cherry (Prunus avium) is a commercially vital fruit crop in China. Hop stunt viroid (HSVd) infection in sweet cherry causes dappled fruit. This study investigated the mechanism of dappled fruit formation in HSVd-infected sweet cherry using integrated metabolomics and transcriptomics. Dappled and non-dappled peel tissues were sampled at the color change and ripening stages. Ultra-performance liquid chromatography-tandem mass spectrometry identified 181 flavonoid metabolites, with peonidin-3-O-rutinoside, cyanidin-3-O-glucoside, peonidin-3-O-glucoside, cyanidin-3-O-arabinoside, cyanidin 3-xyloside, and cinchonain Ic being significantly enriched in dappled areas. RNA-seq revealed 3,287 differentially expressed genes, with PaCHS, PaCHI, PaDFR, and PaANS upregulated in dappled areas at the early stage, correlating with anthocyanin accumulation. KEGG enrichment highlighted anthocyanin and flavonoid biosynthesis pathways as central to pigmentation. This study suggests that HSVd disrupts anthocyanin biosynthesis to induce dappled pigmentation, offering novel insights into viroid-host interactions affecting fruit color in sweet cherry.

Tetracycline, a widely used antibiotic, accumulates in agricultural soils and poses significant risks to crop development and soil health. This study elucidates novel mechanisms of TC phytotoxicity by demonstrating its specific binding to the structurally conserved A-site of ribosomal small subunit RNA (SSU rRNA) in plant mitochondria and chloroplasts-organelles of prokaryotic origin. Through integrated physiological, transcriptomic, and structural analyses, we show that TC disrupts ribosomal function, induces oxidative stress, and impairs photosynthesis and antioxidant defense in soybean, and unbalances the SSU/LSU (ribosomal large subunit RNA) rRNA ratio. We further developed a comprehensive Ecological Risk Index (ERI) framework that integrates soil physicochemical properties, enzyme activities, microbial metabolism, and community structure to evaluate soil microecological shifts under TC stress. Metagenomic analysis uncovered functional adaptations in microbial nitrogen/phosphorus cycling and emphasized the role of multidrug resistance genes-rather than tetracycline-specific resistance-via mobile genetic elements, including those from ssDNA viruses. Our findings provide unprecedented insights into the evolutionary conservation of ribosomal targets of antibiotics and establish a holistic framework for assessing the ecological impact of antibiotic residues in agroecosystems.

Within species, individuals of the same age can differ in size. Previously, parental genetics, nutrition, space and social interactions have been suggested to explain different growth rates. However, direct effects of larger individuals on the physiology and growth of smaller individuals are poorly understood. In this study, we investigated how larger individuals of the marine worm Platynereis dumerilii can impact the growth of smaller conspecifics. Comparing growth distributions in communally and individually reared worms, we show that larger worms suppress the growth of smaller ones. Furthermore, we were able to demonstrate that this suppression is chemically mediated. The chemical cue does not originate from faeces but is water soluble, stable for several days and smaller than 3&#x2005;kDa. Our findings highlight the importance of non-reproduction-related chemical signalling, showing evidence that dominant individuals can chemically suppress the growth of their conspecifics. This study provides new insights into how hierarchy can be established and maintained in a population and is particularly relevant for the growing community studying this model species.

Diseases caused by Begomovirus are a severe obstacle for dicotyledonous plants worldwide. In Bihar, a northern Indian state, we have been seeing indicators of stunting and chlorosis in lentil plants, with an incidence of 2.90%. Based on the series of tests between 2021 and 2024, the suspected organism was determined to be Begomovirus. After restriction digestion, HindIII and BglI, the RCA of three DNA samples revealed a linearized DNA of about&#x2009;~&#x2009;2.7&#xa0;kb. With a genomic organization consisting of two ORFs in virion-sense and five ORFs in complementary sense separated by IR region, the associated virus was discovered to have 2746 nucleotide for DNA-A. When compared to the isolates of Mungbean yellow mosaic India virus (MYMIV), the genome sequences of DNA-A and DNA-B exhibited the highest nucleotide identity (98%). A single recombination event has been detected in DNA-A, with the major and minor parent classified as MYMIV isolates from Bangladesh and Paskistan, respectively. Two overlapping primers were designed using nucleotide sequence of MYMIV-Lentil isolate in order to amplify the virus's genome. DNA-A and DNA-B showed PCR-mediated amplification rates of 70.8 and 69.6%, respectively, when both primer sets were used. In order to ensure linked virus, whitefly-mediated transmission was tried in a controlled environment. In five examined lentil types, a meagre transmission rate (6.1-7.8%) was observed. The present evidence that a virus infects lentil crop rather than other microbe that cause stunting offers valuable insight for developing effective management measures.

Global climate change is the impact of combined abiotic and biotic stresses negatively affecting plant health and productivity. This study investigated the molecular and cellular responses of Nicotiana benthamiana L. plants to wild-type tomato bushy stunt virus (wtTBSV) infection under conditions of pre-existing heat stress. The experiments were conducted under controlled temperature regimes of 30 &#xb0;C and 37 &#xb0;C in combination with virus challenge. Morphological and biochemical analyses in plants under the influence of combined stress showed the alleviation of disease symptoms, reduction in virus content and reduced expression levels of viral proteins P19 and P33. Under conditions of combined stress, accumulation of hydrogen peroxide and malondialdehyde, as well as activation of the antioxidant enzyme catalase, especially in root tissues, were observed. Notably, at 37 &#xb0;C, virus infection was suppressed despite high levels of oxidative stress, whereas at 30 &#xb0;C, a marked decrease in the expression of host factors was observed. The results indicate that thermal stress modulates virus-host interactions and activates defense mechanisms, including antioxidant and RNA interference pathways. Therefore, temperature adaptation can be considered as a promising strategy for enhancing plant resistance to viral pathogens under climate changes.

The Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway has recently emerged as an important regulator of musculoskeletal development. Inhibition of the pathway with small-molecule JAK inhibitors (jakinibs) may improve tendon development and healing. The goal of the present study was to characterize the effects of blocking JAK1 and 2 during a key postnatal musculoskeletal growth phase in Sprague-Dawley rats (postnatal day (PND) 7-28). We administered vehicle or baricitinib via chow (3&#x202f;mg, or 10&#x202f;mg/kg BW/day), which blocks JAK1 and JAK2, for 21 days and characterized the resulting systemic and musculoskeletal effects. We found a striking reduction in overall growth of the juvenile rats with baricitinib treatment, with a reduction in body weight of &#x223c;30% for males and &#x223c;20% for females at PND 28. The spleen was smaller in size with baricitinib treatment, even after normalization to body weight. Bone and tendon similarly showed decreases in mechanical properties without dramatic changes in material properties. Consistent with the role of JAK2 in growth hormone signaling, circulating IGF-1 levels were &#x223c;65% lower in animals fed baricitinib. Our findings suggest that oral administration of baricitinib impairs postnatal growth and development in juvenile rats, likely through the GH/JAK2/IGF-1 axis. The clinical translation of these preclinical data and potential for similar adverse clinical effects of baricitinib in pediatric subjects is unknown. Baricitinib could provide effective treatment for acromegaly, but clinicians should be cautioned of this potential side effect and strongly consider using alternative treatments in children who have yet to reach full size.

Plant viruses have evolved from being viewed exclusively as pathogens into versatile and powerful tools for modern biotechnology. Among them, Tomato bushy stunt virus (TBSV) holds a special place due to its well-studied molecular biology and unique structural properties. This review systematizes the knowledge on TBSV's dual role as a multifunctional platform. On one hand, we cover its application as a viral vector for the highly efficient expression of recombinant proteins in plants, as well as a tool for functional genomics, including Virus-Induced Gene Silencing (VIGS) and the delivery of CRISPR/Cas9 gene-editing components. On the other hand, we provide a detailed analysis of the use of the stable and monodisperse TBSV virion in nanobiotechnology. Its capsid serves as an ideal scaffold for creating next-generation vaccine candidates, platforms for targeted drug delivery to tumor cells, and as a building block for the programmable self-assembly of complex nanoarchitectures. In conclusion, key challenges limiting the widespread adoption of the platform are discussed, including the genetic instability of vectors and difficulties in scalable purification, along with promising strategies to overcome them.

A single-gene mutation inhibits maize silk growth, delivering a novel genetic approach to pollination control with an attractive potential for application in baby corn breeding.

Hop stunt viroid (HSVd) infects a variety of natural hosts, including fruit trees, leading to significant economic losses worldwide. This survey aimed to assess the incidence of HSVd in fruit trees in southern Kazakhstan. Out of 482 fruit trees examined, 28 (5.81%) were found to be infected with HSVd. The incidence was significantly higher in stone fruit trees (8.15%; 22/270) compared to pome fruit trees (2.82%; 6/212; p = 0.0133). Apricots had the highest infection rate at 12.66% (10/79), while pears had the lowest rate at 2.08% (1/48). Fifteen of the identified viroids were cloned for full-genome sequencing. Sequence analysis revealed a high percentage of nucleotide sequence similarity (99-100%) among the Kazakhstani HSVd isolates, suggesting a possible unique origin for the infection. We also identified several SNPs of HSVd that have not been previously documented. A phylogenetic analysis indicated that the Kazakhstani HSVd variants clustered together in a separate group, distinct from the five known groups of HSVd. This potentially new group displayed differences in its predicted secondary structure compared to other viroid groups. These findings emphasize the need for the development of effective control measures for HSVd and other viroids affecting fruit trees.

Watermelon chlorotic stunt virus (WmCSV), a bipartite begomovirus, poses a severe and expanding threat to global cucurbit and watermelon production, driving an urgent need to unravel its genetic diversity indices and evolutionary complexities. To elucidate its evolutionary history, this study investigated the genetic diversity, evolutionary dynamics, and global dispersal of its genomic components, DNA-A (WmA) and DNA-B (WmB). The analyses uncovered striking contrasts between the components. WmB exhibited markedly greater genetic diversity (&#x3c0; = 0.0508 vs. 0.0119 for WmA), a slightly faster evolutionary rate (1.26 &#xd7; 10-4 vs. 1.44 &#xd7; 10-3 substitutions/site/year), and a far more complex recombination profile, with 34 events detected compared to only one in WmA. The abundance of recombination breakpoints in WmB underscores its central role in shaping genomic variability and adaptive potential. Phylogenetic analyses of both components unveil eight robustly supported clades per segment, predominantly shaped by geographical boundaries, hinting at localized evolutionary trajectories with constrained long-distance gene flow, with the exception of Oman. Bayesian time-scaled phylogenies and phylogeographic reconstructions further illuminate distinct dissemination pathways, suggesting an intriguing origin, with WmA likely emerging from the United States and WmB tracing back to Saudi Arabia, while the Middle East emerges as a dynamic epicenter for regional spread and subsequent incursions into the Americas. Together, these findings reveal contrasting evolutionary forces driving WmCSV diversification and provide critical insights into its origins and ongoing global emergence.