Search Results (382)

Between 2022 and 2024, a severe branch dieback disease was observed affecting over 6% of sweet cherry trees of the ‘Tieton’ cultivar in commercial greenhouses in southern Liaoning Province, China. Symptoms primarily occurred at the top of young branches. At the early stage of disease onset, the lesions appeared as dark brown, irregularly shaped areas with a moist surface; as the disease progressed, these lesions turned dry and rotten, leading to tree decline symptoms in sweet cherry trees. Disease diagnosis was carried out in sweet cherry greenhouses across Liaoning Province, where 24 diseased samples were collected and 14 fungal isolates were obtained therefrom. Based on morphological traits, cultural characteristics, and multi-locus phylogenetic analyses of the internal transcribed spacer (ITS) region, beta-tubulin (TUB2) gene, and translation elongation factor 1-α (TEF1) gene, these isolates were identified as Botryosphaeria dothidea. Two representative isolates, namely zdcy-1 and zdcy-2, were selected for pathogenicity assays. Both mycelial plug and spore suspension inoculation methods confirmed the pathogenicity of the pathogen. The biological characteristic assays revealed that the optimal temperature range for the pathogen’s mycelial growth on PDA medium was 25–28 °C, and the optimal pH range was 6.0–8.0. This study improves the understanding of branch dieback disease in sweet cherry orchards in China, enriches the knowledge regarding the geographical distribution, host range, and infection sites of the pathogen, and provides novel insights for the management of sweet cherry diseases. Full article

Quantitative real-time PCR (qPCR) remains a cornerstone method for analyzing gene expression due to its high sensitivity, specificity, and reproducibility. However, for reliable results in relative quantification studies, the choice of an appropriate reference gene is critical to ensure accurate normalization. The expression of commonly used reference genes can vary depending on developmental stage and experimental conditions, making their validation essential. To date, no validated reference genes have been reported for Agrostemma githago L. (corn cockle, Caryophyllaceae). To facilitate research on genes involved in natural product biosynthesis and specialized metabolism regulation, we aimed to identify the most stable reference genes across various plant organs and cultivation conditions of this species. Drawing on previous literature, we have selected seven housekeeping genes widely used for evaluation: actin, β-tubulin, elongation factor 1α, glyceraldehyde-3-phosphate dehydrogenase, histone H3, translation elongation factor 1, and eukaryotic translation initiation factor 5A1 (for which two primer sets were tested). The nucleotide sequences of these potential reference genes were identified from the A. githago transcriptome. Using qRT-PCR, transcript levels of seven potential reference genes were estimated in 40 different A. githago samples, including 25 in vitro samples under various treatment conditions and 15 soil-grown samples representing A. githago organs in different developmental stages. Expression stability of candidate reference genes was assessed using the RefFinder platform, which combines four commonly applied statistical algorithms: geNorm, NormFinder, BestKeeper, and the comparative Δ-Ct method. The results revealed that the selection of optimal reference genes varied based on the particular organ, developmental stage and condition being examined. TIF5A1-2 (one of the two primer pairs tested) and GAPHD consistently exhibited the most stable expression under various conditions in vitro. EF1α and H3 exhibited superior performance across different organs of soil-grown plants. Moreover, our integrated analysis enabled the identification of the two most stable, universal reference genes suitable for normalization in A. githago under all tested conditions—H3 and TIF5A1-2. Our work provides a robust foundation for future transcriptomic and functional studies of the specialized metabolism of A. githago and other related species. Full article

The function of the highly conserved GTPase LepA, a homolog of elongation factor EF-G, remains unknown in translation. However, there is biochemical data that it implicates in the 30S ribosomal subunit biogenesis. Here, using cryo-electron microscopy, we characterized 30S subunits isolated from an Escherichia coli strain with a deleted lepA gene. The cryo-EM maps for ∆lepA 30S particles were divided into classes corresponding to consecutive assembly intermediates: from particles characterized by unformed helices h44/h45 of the central decoding center (CDR) and highly flexible head, through intermediates with a distorted CDR and a partial stabilization of the head, to near-mature 30S subunits with correctly docked h44 in the CDR, accessible 3′ end of 16S rRNA for translation but significant flexibility in head domain. Cryo-EM analysis of ΔlepA 30S intermediates revealed that they predominantly proceed to nearly mature functional state and exhibit suboptimal flexibility in the head domain. This finding suggests that LepA likely contributes to the final proper stabilization of the 3′ domain of the 30S subunit during ribosome assembly. Full article

The detection of zeranol in grazing cattle could be explained by the metabolization of the mycotoxin, zearalenone (ZEA), which was proven to be naturally contaminating the grasses harboring the Fusarium species. Previous studies have suggested that members of the Fusarium incarnatum–equiseti species complex (FIESC) could be responsible for this contamination. Therefore, the objective of this study is to determine the species composition of FIESC isolates isolated from natural and cultivated pastures previously intended for livestock feed in Argentina and to analyze their ability to produce ZEA. Twenty-five Fusarium isolates were characterized by a phylogenetic analysis of the translation elongation factor 1α, and their ZEA production was quantified by cultivation in rice and subsequent analysis by UPLC-MS/MS. The phylogenetic analysis revealed a high genetic diversity identifying five isolates as species already described in the FIESC and six linages which could represent putative new phylogenetic species. In addition, 76% of the isolates were able to produce ZEA, even in high quantities. In conclusion, grasses used for grazing cattle in Argentina harbor a high diversity of FIESC species, many of which are potentially new and capable of producing ZEA, confirming their role as a likely source of this mycotoxin contamination in pastures and improving our understanding of mycological risk in livestock production systems. Full article

Background/Objectives: The selection and validation of species-specific housekeeping genes (HKGs) have become increasingly common in functional genomics, with application of quantitative Polymerase Chain Reaction (qPCR) or cDNA-based qPCR (RT-qPCR). Despite the Macrobrachium amazonicum having RNA-seq studies available, there are still no data on the most stable and consistent HKGs for use in relative gene expression analyses. Therefore, the present study aimed to identify and validate seven HKGs in M. amazonicum: Eukaryotic Translation Initiation Factor (EIF), 18S ribosomal RNA (18S), Ribosomal Protein L18 (RPL18), β-actin, α-tubulin (α-tub), Elongation Factor 1-α (EF-1α), and Glyceraldehyde-3-phosphate Dehydrogenase (GAPDH). Methods: The HKGs were identified in the M. amazonicum transcriptome, characterized for identity confirmation, and compared against public databases. Subsequently, RT-qPCR assays were prepared using muscle, hepatopancreas, gills, testis, androgenic gland, and ovary to assess the stability of the HKG markers, employing the comparative ∆Ct, BestKeeper, NormFinder, and GeNorm methods. Results: All candidate HKGs identified showed high similarity with other decapods. Reactions performed with these markers demonstrated high specificity, PCR efficiency, and elevated coefficients of determination. The comprehensive ranking, indicated that no single HKG was stable across all tissues, with HKGs showing the best stability being tissue-specific. The most stable HKGs were RPL18 and 18S. GAPDH, historically used as an HKG, showed the poorest performance in stability ranking for most tissues tested, whereas β-actin was most suitable only for ovarian. Conclusions: These data reinforce the need for species-specific HKG validation and provide an appropriate panel of reference markers for gene expression studies in the M. amazonicum. Full article

Streptococcus suis is an important zoonotic pathogen responsible for severe infections in pigs and humans. Its capacity to survive within phagocytic cells is considered a key virulence mechanism that contributes to dissemination and persistence in host tissues. This study employed comparative proteomic profiling to investigate intracellular adaptation of S. suis serotypes 2 (SS2) and 14 (SS14) during infection of human U937 macrophages. Five isolates originating from humans and pigs were analyzed using gel electrophoresis with liquid chromatography–tandem mass spectrometry (GeLC–MS/MS), revealing 118 differentially expressed proteins grouped into 11 functional categories. Translation-related proteins represented the largest group (48%), including upregulated ribosomal subunits (30S: S2, S5, S7, S8, S12, S15; 50S: L1, L5, L18, L22, L24, L33, L35) and translation factors such as GidA/TrmFO and RimP. Enrichment of carbohydrate metabolism and DNA replication proteins, including phosphoenolpyruvate carboxylase (PEP), UDP-N-acetylglucosamine pyrophosphorylase (GlmU), and ATP-dependent DNA helicase RuvB, indicated metabolic reprogramming and stress adaptation under intracellular conditions. Stress-response proteins such as molecular chaperone DnaK were also induced, supporting their multifunctional, “moonlighting” roles in virulence and host interaction. Comparative analysis showed that SS2 expressed a broader range of adaptive proteins than SS14, consistent with its higher virulence potential. These findings reveal conserved intracellular responses centered on translation, energy metabolism, and stress tolerance, which enable S. suis to survive within human macrophages. Integration of these intracellular proteomic signatures with previous exoproteomic, peptidomic, and network-based studies highlights translational and metabolic proteins—particularly DnaK, enolase, elongation factor EF-Tu, and GlmU—as multifunctional candidates linking survival and immunogenicity. This work establishes a comparative proteomic foundation for understanding S. suis intracellular adaptation and highlights potential targets for future vaccine or therapeutic development against this zoonotic pathogen. Full article

Wheat is a major staple crop in Xinjiang, China; however, comprehensive data on Fusarium mycotoxin contamination in wheat from this region remain limited. Despite recent observations of Fusarium head blight (FHB), few studies have characterized the mycotoxin profiles in wheat from Xinjiang, especially regarding emerging mycotoxins. This study aimed to systematically investigate the occurrence of both conventional and emerging mycotoxins in freshly harvested wheat from Xinjiang, to evaluate the effects of sampling year and geographical region on mycotoxin contamination levels, and to identify the Fusarium species responsible for mycotoxin production. A total of 151 freshly harvested wheat samples were collected from Southern and Northern Xinjiang in 2023 and 2024. Mycotoxins were quantified using high-performance liquid chromatography–tandem mass spectrometry (HPLC-MS/MS). Fusarium isolates were obtained and identified through the translation elongation factor 1-alpha (TEF-1α) gene sequencing. Genotyping was assessed by genotype-specific multiplex PCR, and mycotoxigenic potential was detected by rice culture assays. A high incidence (72.9%) of co-contamination with multiple mycotoxins was observed. Conventional mycotoxins such as deoxynivalenol (DON) and zearalenone (ZEN) were detected in 31.1% and 41.1% of samples. Notably, emerging mycotoxins, including enniatins (ENNs) and beauvericin (BEA), were present at significantly higher concentrations than those reported in some regions of China. Significant spatiotemporal variation was observed, with markedly higher contamination levels of emerging mycotoxins in 2024, particularly in Northern Xinjiang, where the symptoms of FHB epidemic occurred due to the humid climate and maize–wheat rotation system. Fusarium graminearum was identified as the primary producer of conventional mycotoxins, while F. acuminatum and F. avenaceum were mainly associated with emerging mycotoxins except BEA. This study provides the first comprehensive dataset on the co-occurrence of conventional and emerging Fusarium mycotoxins in wheat from Xinjiang and highlights significant spatiotemporal variations influenced by environmental factors. These findings underscore the necessity for continuous, region-specific monitoring and effective risk management strategies to address the evolving mycotoxin threat in Xinjiang’s wheat. Future research should focus on characterizing the populations of Fusarium toxin-producing fungi and the long-term impacts of mycotoxin exposure on food safety. Full article

Surveys conducted in a nursery located in eastern Sicily, southern Italy, revealed the presence of plants of Vachellia nilotica (syn. Acacia arabica), V. farnesiana (syn. A. farnesiana) and Pithecellobium dulce showing symptoms of trunk and branch canker, shoot dieback and general decline. Laboratory fungal isolation from wood tissues showed high percentage of Diaporthe-like (60–62%) and Botryosphaeriaceae-like fungi (21–85%) constantly associated with the diseased samples. Subsequent molecular characterization of recovered isolates was based on sequencing of the complete internally transcribed spacer region (ITS), the translation elongation factor 1-alpha (tef1) and the beta-tubulin (tub2) regions, followed by multi-locus phylogenetic analyses. The isolates collected from symptomatic tissues were phylogenetically characterized as Diaporthe foeniculina and Neofusicoccum parvum. Pathogenicity tests were conducted on Acacia and P. dulce plants and results showed that both species were pathogenic, being able to induce necrotic lesions on the stem. To our knowledge this is the first report worldwide of D. foeniculina and N. parvum infecting A. arabica, A. farnesiana and P. dulce. Full article

Fusarium crown rot (FCR) is a devastating fungal disease of wheat in China that causes substantial yield losses and deterioration of grain quality. To clarify the pathogen composition and associated mycotoxin risks of FCR in Hebei Province, a comprehensive field survey was conducted during the critical growth stage from flowering to maturity (April to May) of the 2024 wheat season from 46 sites. Fungal isolates were obtained from symptomatic wheat stem bases and were identified through morphological and molecular analyses. In total, 156 Fusarium isolates were obtained, and from these isolates, 12 Fusarium species were identified based on species-specific PCR and DNA sequencing of the translation elongation factor 1-α (TEF1) loci. Of these Fusarium isolates, 118 were identified as Fusarium pseudograminearum, 16 identified as F. graminearum and the remaining isolates consisted of F. acuminatum, F. asiaticum, F. boothii, F. culmorum, F. equiseti, F. flocciferum, F. incarnatum, F. proliferatum, F. sinensis, and F. verticillioides. The results revealed that F. pseudograminearum with the 15ADON genotype was the predominant species, accounting for 75.64% of all the isolates, followed by F. graminearum. Trichothecene genotyping revealed that 91.53% of the F. pseudograminearum strains possessed the 15ADON genotype (108 isolates), while 8.47% exhibited the 3ADON genotype (10 isolates). Although differences were observed within F. pseudograminearum in MAT1-1 and MAT1-2 distributions among different sampling regions, a well-balanced mating type ratio was identified across Hebei Province. Population genetic analysis based on composite genotypes (trichothecene and mating type) revealed moderate to high genetic diversity within the F. pseudograminearum population. Recent studies on causal Fusarium species, trichothecene genotypes, and their distribution in China are compared and discussed. These findings may have implications in managing this significant fungal disease. Full article

Acer saccharum Marsh., valued for its ornamental, material, and edible uses, is an important temperate tree species in the Northern Hemisphere. A blight disease affecting branches of A. saccharum was first identified in 2023 in Shandong, China. The causal agent was identified as Botryosphaeria wangensis G.Q. Li & S.F. Chen based on cultural and morphometric characteristics. Phylogenetic analysis was performed by amplifying and sequencing the internal transcribed spacer (ITS) region of rDNA, the translation elongation factor 1α (tef1) partial gene, the β-tubulin (tub2) partial gene, and the second largest subunit of RNA polymerase II (rpb2), in combination with morphological data. Symptoms observed in the field were replicated in a pathogenicity test through inoculation of A. saccharum branches, thus satisfying Koch’s postulates. To our knowledge, this is the first report worldwide of B. wangensis infecting A. saccharum. Full article

Maize (Zea mays L.) is a cornerstone of food security and livestock production in Paraguay. However, its productivity and grain safety are increasingly threatened by Fusarium species because of their pathogenic capacity and ability to produce mycotoxins. In this study, symptomatic maize leaves collected from commercial fields in Pirapó, Itapúa, during the 2022 growing season were processed to isolate and characterize fungal pathogens. Three isolates displaying typical Fusarium morphology were obtained and examined through macroscopic and microscopic traits. Molecular identification was conducted using translation elongation factor 1-α 1-α (TEF) sequences, followed by phylogenetic inference using maximum likelihood and Bayesian methods. The Paraguayan isolates (PYF-MZE22-01, -02, -03) clustered with the ex-type strain Fusarium awaxy CBS139380 in a strongly supported clade, confirming species identity. This finding constitutes the first record of F. awaxy associated with maize in Paraguay, thereby expanding its known geographical distribution. Considering that members of the Fusarium fujikuroi species complex are recognized producers of regulated mycotoxins, the detection of F. awaxy raises concerns regarding its pathogenic potential and possible implications for food safety. These results underscore the importance of integrating molecular diagnostics, toxigenic profiling, and surveillance programs to monitor emerging Fusarium taxa in South American agroecosystems. Full article

The genus Cunninghamella is widely distributed, primarily saprotrophic, occasionally endophytic and phytopathogenic. Analysis based on the internal transcribed spacer (ITS), the large subunit (LSU) of ribosomal DNA, and translation elongation factor 1 alpha (TEF1α), along with morphological comparisons, resulted in a discovery of eight new species. Molecular phylogenetic analyses placed each of these new species within well-supported clades. Cunninghamella crassior sp. nov., with short and thick spines, and C. fusca sp. nov. with brown sporangiola, are sister clades to each other. C. diffundens sp. nov., containing dispersed granules in sporangiola, is closely related to C. irregularis Zhao. C. tuberculata sp. nov., producing sporangiola with nodule-like protrusions. C. fulvicolor sp. nov., sister to C. irregularis, forms yellowish-brown pigmented colonies. C. guttulata sp. nov., with teardrop-shaped sporangiola, and C. inaequalis sp. nov., with uneven sporangiola, are both closely related to C. regularis Zhao. C. monosporangiola sp. nov., characterized by only one sporangiolum on some vesicles, is sister to C. verrucosa Zhao. This study represents the eleventh installment in a series investigating early-diverging fungal diversity in China and expands the number of accepted species in Cunninghamella to 39. Full article

Sporothrix schenckii is a pathogenic fungus with both clinical and environmental origins that was traditionally described as a single species but is increasingly recognized as being genetically diverse. In this study, we analyzed multiple isolates recovered from human sporotrichosis cases and environmental sources across Latin America (Mexico, Guatemala, Colombia). We conducted a polyphasic analysis of 16 isolates, integrating morphological data with multilocus sequence analysis (MLSA) targeting the internal transcribed spacer (ITS), calmodulin (CAL), β-tubulin (BT2), and translation elongation factor 1-α (TEF) gene regions. Phylogenetic relationships were resolved via maximum likelihood, and genetic structure was corroborated via four independent clustering methods: minimum spanning tree, principal component analysis, multidimensional scaling, and self-organizing maps. MLSA reidentified six isolates as S. globosa and confirmed the absence of S. brasiliensis in the cohort. The remaining S. schenckii s. str. isolates were resolved into three clades (A, B, and C). Notably, clade B (EH748, EH194, and EH257) formed a genetically divergent cluster with the highest nucleotide diversity (π = 0.03556) and was consistently segregated by all clustering algorithms. Clinical and environmental isolates were phylogenetically intermingled, supporting an active environmental reservoir for human infections. Phenotypic data, including colony size and conidial and yeast dimensions, varied but did not clearly distinguish between clinical and environmental origins. Our study provides compelling molecular evidence for a previously unrecognized, highly divergent clade within S. schenckii s. str., indicative of ongoing cryptic speciation. These findings refine the taxonomy of medically important Sporothrix species and reveal a distinct epidemiological profile for sporotrichosis in the studied regions, separate from the S. brasiliensis-driven epizootic. This highlights the critical role of molecular surveillance for accurate diagnosis, treatment, and public health strategies. Full article

Plants, as sessile organisms, rely on sophisticated gene regulatory networks (GRNs) to adapt to dynamic environmental conditions. Among the central components of these networks are the interconnected pathways of light signaling and circadian rhythms, which together optimize growth, development, and stress resilience. While light and circadian pathways have been extensively investigated independently, their integrative coordination in mediating climate change adaptation responses remains a critical knowledge gap. Light perception via photoreceptors initiates transcriptional reprogramming, while the circadian clock generates endogenous rhythms that anticipate daily and seasonal changes. This review explores the molecular integration of light and circadian signaling, emphasizing how their crosstalk fine-tunes GRNs to balance resource allocation, photomorphogenesis, and stress adaptation. We highlight recent advances in systems biology tools, e.g., single-cell omics, CRISPR screens that unravel spatiotemporal regulation of shared hubs like phytochrome-interacting factors (PIFs), ELONGATED HYPOCOTYL 5 (HY5), and CIRCADIAN CLOCK ASSOCIATED 1 (CCA1). Here, we synthesize mechanistic insights across model and crop species to bridge fundamental molecular crosstalk with actionable strategies for enhancing cropresilience. Moreover, we have tried to discuss agricultural implications in engineering light–clock interactions for the enhancement in crop productivity under climate change scenarios. Through synthesizing mechanistic insights and translational applications, this work will help underscore the potential for manipulating light–circadian networks to promote sustainability in agriculture. Full article

The fruiting stage of soybean (Glycine max L.) is critical for determining both its yield and quality, thereby influencing global production. While some studies have provided partial explanations for the occurrence of Fusarium species on soybean seeds and pods, the fungal diversity affecting soybean pods in Sichuan Province, a major soybean cultivation region in Southwestern China, remains inadequately understood. In this study, 182 infected pods were collected from a maize–soybean relay strip intercropping system. A total of 10 distinct pod-infecting fungal genera (132 isolates) were identified, and their pathogenic potential on soybean seeds and pods was evaluated. Using morphological characteristics and DNA barcode markers, we identified 43 Fusarium isolates belonging to 8 species, including F. verticillioides, F. incarnatum, F. equiseti, F. proliferatum, F. fujikuroi, F. oxysporum, F. chlamydosporum, and F. acutatum through the analysis of the translation elongation factor gene (EF1-α) and RNA polymerases II second largest subunit (RPB2) gene. Multi-locus phylogenetic analysis, incorporating the Internal Transcribed Spacer (rDNA ITS), β-tubulin (β-tubulin), Glyceraldehyde 3-phosphate dehydrogenase (GADPH), Chitin Synthase 1 (CHS-1), Actin (ACT), Beta-tubulin II (TUB2), and Calmodulin (CAL) genes distinguished 37 isolates as 6 Colletotrichum species, including C. truncatum, C. karstii, C. cliviicola, C. plurivorum, C. boninense, and C. fructicola. Among these, F. proliferatum and C. fructicola were the most dominant species, representing 20.93% and 21.62% of the isolation frequency, respectively. Pathogenicity assays revealed significant damage from both Fusarium and Colletotrichum isolates on soybean pods and seeds, with varying isolation frequencies. Of these, F. proliferatum, F. acutatum, and F. verticillioides caused the most severe symptoms. Similarly, within Colletotrichum genus, C. fructicola was the most pathogenic, followed by C. truncatum, C. karstii, C. cliviicola, C. plurivorum, and C. boninense. Notably, F. acutatum, C. cliviicola, C. boninense, and C. fructicola were identified for the first time as pathogens of soybean pods under the maize–soybean strip intercropping system in Southwestern China. These findings highlight emerging virulent pathogens responsible for soybean pod decay and provide a valuable foundation for understanding the pathogen population during the later growth stages of soybean. Full article