Author: slquinlan

Plant Physiol. 2026 Oct 30:kiag803. doi: 10.1093/plphys/kiag803. Online ahead of print.

ABSTRACT

Soil boron deficiency is a global abiotic stress, negatively impacting on crop yield. In the dicot model species Arabidopsis thaliana, inhibition of root elongation is one of the earliest symptoms of boron deficiency. In the monocot model maize (Zea mays L.), boron deficiency-induced root defects are widely unexplored. In this study, we assessed boron deficiency-induced defects in the primary root system of maize and tested the suitability of phenylboronic acid (PBA) as boron deficiency mimic by performing phenotypic, histological, molecular, and biochemical analyses. Our analyses showed that boron deficiency and PBA resulted in similar defects in primary root elongation and lateral root density. The PBA-induced defects, however, were much stronger than those induced by boron deficiency, particularly regarding lateral root development. We provide evidence that the PBA-induced defects were caused by the boric acid moiety and show that both boron deficiency and PBA altered the levels of auxin and reactive oxygen species. Strikingly, PBA did not affect rhamnogalacturonan-II (RG-II) dimerization. Interference of boron-mediated RG-II crosslinking, however, was previously proposed to be the mode of action of PBA in planta. Our study shows that PBA is particularly suited for the molecular dissection of lateral root development in maize and suggests that PBA does not mimic known molecular boron deficiency responses.

PMID:42960663 | DOI:10.1093/plphys/kiag803

Plant Physiol Biochem. 2026 Oct 26;240:111896. doi: 10.1016/j.plaphy.2026.111896. Online ahead of print.

ABSTRACT

The soybean gene Glyma.20G085100 (Gm20P), contributing to the cqSeed protein-003 QTL, and its paralog Glyma.10G134400 (Gm10P), were edited using the CRISPR/Cas9-based genome editing reagents. Two mutants, a gm20p single mutant and a gm10p gm20p double mutant devoid of editing reagents, were identified. Additional gm10p and gm20p single mutants were isolated from F2 population of the cross between the gm10p gm20p double mutant and the wild-type Thorne. The above mutants were characterized in different growing conditions. Seed protein content of the gm10p single and the gm10p gm20p double mutant were significantly reduced relative to the gm20p single mutant and Thorne, with a concomitant increase in oil and starch content. A delayed maturity phenotype was observed in the gm20p single, the gm10p single, and gm10p gm20p double mutants under field conditions across multiple environments. Under controlled conditions in a growth chamber, prominent delayed maturity was only observed under short-day conditions, while long-day conditions induced phenotypic changes in growth in the gm10p gm20p double mutant, but slight delay in maturity. Transcriptomic analysis revealed that the gm10p gm20p double mutant exhibited repression of genes involved in light signaling, enhanced expression of JAZs in JA signaling, suppression of ABA-responsive and senescence-related genes, and elevation of genes that inhibit IAA signaling. Furthermore, the gm10p gm20p double mutant displayed higher sensitivity to salt and ABA during germination. Collectively, these results suggest that both Gm10P and Gm20P modulate light signaling and impact soybean development, maturity and seed reserve content.

PMID:42945731 | DOI:10.1016/j.plaphy.2026.111896

Am J Bot. 2026 Oct 27:e70282. doi: 10.1002/ajb2.70282. Online ahead of print.

ABSTRACT

PREMISE: Gynodioecy is maintained through female advantage in seed fitness that depends on the sex ratio of a population. We hypothesized that females of Silene acaulis would exhibit floral traits associated with elevated outcross pollination and that sex ratio would impact pollen limitation and inbreeding depression such that female advantage is greatest at high hermaphrodite frequency.

METHODS: We examined how sex ratio affects female advantage by pairing observations of floral morphology and natural pollination with a pollination experiment in two sites that differed in sex ratio. We described the population structure of sex ratio by comparing site sex ratio to local scale sex ratio within 1 m of focal plants.

RESULTS: We found evidence for frequency dependence of female advantage through pollination. As local hermaphrodite abundance increased, females were more likely to receive pollen and set fruit. Sex ratio was spatially structured, and only local sex ratio had significant effects on reproductive processes. Both sexes were similarly severely pollen limited, but longer stigmas on female flowers increased chances of pollen deposition. Hermaphrodites experienced inbreeding depression expressed during seed germination, but inbreeding did not fully explain female advantage.

CONCLUSIONS: We confirm female reproductive advantage in a gynodioecious species and show that it is partly facilitated by superior pollination-mediated seed production due to longer stigmas which maximizes pollen receipt. Female advantage exhibits negative frequency dependence locally, such that female advantage is greatest when nearby hermaphrodites are abundant. These results advance our understanding of links between population reproductive processes and sexual selection.

PMID:42947368 | DOI:10.1002/ajb2.70282

Biochem J. 2026 Oct 28:BCJ20260401. doi: 10.1042/BCJ20260401. Online ahead of print.

ABSTRACT

Plant cell walls are made of complex polymeric networks of diverse polysaccharides, proteins, polyphenolics, and glycoproteins called hydroxyproline-rich glycoproteins (HRGPs), like arabinogalactan proteins or AGPs. Approximately 90 to 98% of the mass of AGPs is composed of polysaccharide components, which are synthesized by a group of enzymes known as glycosyltransferases (GTs). One subset of these enzymes comprises a family of fucosyltransferases (FUTs) that transfer fucose (Fuc) residues to the arabinose (Ara) moiety of AGP. Ten FUTs involved in plant cell wall polymer synthesis have been identified in Arabidopsis thaliana, three of which have been characterized: AtFUT1, a xyloglucan-specific FUT, and AtFUT4 and AtFUT6, which are AGP-specific FUTs. In this study, we determined the crystal structure of AtFUT4 to gain insights into its substrate specificity toward GDP-Fuc (donor substrate) and AGP-based oligo- and polysaccharides (acceptor substrates). Through integrated bioinformatics and biochemical analyses, we identified key features that define acceptor- and donor-specificities. We tested two acceptors, AGPs and the pseudo-substrate arabinotetrose, and identified critical residues that contribute to acceptor recognition. In addition to identifying residue-level interactions, our analysis highlights the importance of structural flexibility: tighter binding of GDP-fucose by AtFUT4 likely enables broader acceptor specificity compared with AtFUT1, while also increasing donor hydrolysis in the absence of acceptor. Overall, the study advances understanding of the structure-function relationship of AtFUT4 in AGP fucosylation and provides a foundation for rational engineering of GTs, particularly FUTs, development of inhibitors, studies of cell wall polysaccharide interactions, and exploration of the roles of AtFUT4 in plant physiology.

PMID:42949158 | DOI:10.1042/BCJ20260401

Plant Biotechnol J. 2026 Oct 28. doi: 10.1111/pbi.70779. Online ahead of print.

ABSTRACT

Plant cell walls are polysaccharide-rich extracellular matrices composed of multiple complex carbohydrate polymer networks, including cellulose, hemicelluloses, pectins, and glycosylated proteins. Polysaccharide deposition critically impacts cell wall structure, and structural microheterogeneity within cell wall glycans also influences polymer rigidity and polymer-polymer interactions. Collections of monoclonal antibodies (mAbs) have been developed to target unique carbohydrate epitopes within cell wall polysaccharides and to investigate how these structural changes impact cellular and plant development. Here, we implement generalizable methods to attach unique DNA barcodes to mAbs that recognize major cell wall polysaccharide classes. By applying these mAbs individually to polysaccharide standards, we demonstrate that bound DNA barcoded antibody abundance can be measured via quantitative PCR. Additionally, we demonstrate that DNA-conjugated antibodies can be pooled to quantitatively analyze polysaccharide epitope composition of polysaccharide standards and fractionated cell wall material by amplifying their unique barcodes via qPCR. These results demonstrate that barcoded polysaccharide-directed mAbs offer sensitive, quantitative insights into cell wall polysaccharide composition and facilitate multiplexed profiling of cell wall polysaccharide abundance. This approach will also enable multiple future high-throughput applications, such as glycome profiling, spatial glycomics, and glycan interaction measurements, that will further our understanding of cell wall compositional impacts on plant physiology.

PMID:42949253 | DOI:10.1111/pbi.70779

Curr Issues Mol Biol. 2026 Sep 22;48(10):973. doi: 10.3390/cimb48100973.

ABSTRACT

The use of wheat as forage remains underutilized, particularly in the southeastern U.S., despite its potential to fill seasonal forage gaps when warm-season forages are dormant. Genetic improvement of forage yield traits in wheat has been limited. A genome-wide association study on 182 soft red winter wheat lines was conducted to identify quantitative trait loci for five forage yield traits. The panel was evaluated across four environmental-year combinations in Georgia (2023-2025). ANOVA revealed significant phenotypic variation, with heritability ranging from low to moderate in combined locations and from low to high within individual locations. Correlation analysis revealed significant positive associations between growth stages (GS), forage height (FHt), fresh forage weight (FWt), and dry forage weight (DWt). Using 47,339 SNP markers, we identified 192 marker-trait associations. Twenty-two major-effect QTLs explained 10% of the phenotypic variance, of which six were multi-trait. Chromosomes 7A, 1B, and 6B harbor key regions for FHt, FWt, and DWt. Accumulating favorable alleles showed significant increases in FHt (7 cm), FWt (1611.2 kg/ha), DWt (58.6 kg/ha), and germination counts (G) (4.5%), while reducing GS (0.81 units). QTLs (QFht.uga-7A, QFht.uga-4A) were possibly allelic with known loci, and the remaining 20 QTLs appeared novel. Candidate genes were identified for 10 of 22 QTLs related to plant growth and development. This study provides promising candidates for forage yield improvement in wheat under forage-production systems, supporting marker-assisted selection. Upon further validation, these results can be used in breeding for desirable plant architecture to improve wheat potential for forage yield.

PMID:42939511 | DOI:10.3390/cimb48100973

Appl Environ Microbiol. 2026 Oct 26:e0125626. doi: 10.1128/aem.01256-26. Online ahead of print.

ABSTRACT

Oak wilt, caused by Bretziella fagacearum, is a destructive disease of Quercus species. Symptoms consist of leaf scorch, dieback, defoliation, vascular discoloration, and eventual death. Prompt diagnosis is crucial for timely management that involves laborious and expensive practices such as sanitation, cutting of infected trees, and proactive tree removal to create a buffer zone, root trenching, and/or fungicide injections. Due to these resource-intensive management tactics, laboratory test accuracy and speed are paramount. Diagnoses of oak wilt currently rely on culturing, nested PCR, or qPCR, but all these methods have limitations, ranging from ambiguous results to high barriers to application. We developed a rapid, robust, and sensitive loop-mediated isothermal amplification (LAMP) diagnostic test using primers and probes that target a section of the internal transcribed spacer region of the rDNA of the oak wilt pathogen, B. fagacearum. This assay can detect B. fagacearum from pure isolates and environmental samples, including branch sapwood, leaf petioles, nitidulid sap beetle vectors, and degraded fungal mats. The LAMP assay developed here is sensitive to a detection limit as low as 1 pg/μL and can detect the pathogen in under 20 min. This real-time LAMP-based diagnostic test is thoroughly validated to specifically detect the oak wilt pathogen, B. fagacearum, and is demonstrated to detect the fungus from a variety of routinely collected sample types. Our rapid molecular detection protocol can provide a useful tool for diagnostic labs, forest health practitioners, and researchers studying oak wilt.IMPORTANCEOak wilt is a deadly disease of oaks that represents a growing threat to natural and planted forests throughout eastern North America. To enhance the speed and accuracy of molecular diagnostics for this disease, we designed a molecular test using loop-mediated isothermal amplification (LAMP) to reliably and rapidly detect the oak wilt pathogen, Bretziella fagacearum. To optimize the practicality of this assay in real-world conditions, we developed a rigorous validation process that incorporated the known breadth of genetic diversity of the oak wilt pathogen, sample tissue range, and a panel of non-target fungi to assess the potential for false positives. The novel assay is demonstrated to be highly specific and can detect B. fagacearum from host sapwood, leaf petioles, and nitidulid sap beetles, serving as a versatile new tool for forest health surveillance. Our approach also represents a thorough framework for researchers interested in the development of rapid molecular methods for the detection of forest microbes more broadly.

PMID:42929542 | DOI:10.1128/aem.01256-26

Cell Rep. 2026 Oct 22;45(11):118188. doi: 10.1016/j.celrep.2026.118188. Online ahead of print.

ABSTRACT

Effective survival after injury requires the precise coordination of immune activation and tissue regeneration, yet the molecular mechanisms balancing these opposing processes remain poorly understood. Here, we identify proline transporters as key regulators of this trade-off in plants. Genetic disruption of two wound-induced proline transporters, ProT2 and ProT3, enhances regenerative capacity and abolishes salicylic acid (SA)-mediated suppression of regeneration while preserving SA-responsive gene expression and SA-mediated antibacterial resistance. Mechanistically, a ProT3-CPK1 complex modulates wound-induced reactive oxygen species (ROS), sustaining a ROS level that restricts de novo root regeneration (DNRR) after wounding. Notably, pharmacological inhibition of proline transport functionally separates immune activation from regenerative suppression and promotes regeneration across multiple plant species. These findings support the role of proline transporters as a regulatory hub integrating stress-induced proline metabolism, SA signaling, and ROS homeostasis to coordinate immunity and regeneration, and highlight chemical inhibition of proline transport as a strategy to improve regeneration without compromising immune defense.

PMID:42911812 | DOI:10.1016/j.celrep.2026.118188

Microb Genom. 2026 Oct;12(10). doi: 10.1099/mgen.0.001868.

ABSTRACT

Campylobacter jejuni is a leading cause of foodborne illness worldwide, yet infection sources are not always clear. We used whole-genome sequencing to compare C. jejuni from bird faeces collected in cherry orchards in Michigan to 214 clinical isolates from Michigan patients and 1,286 published bird-derived C. jejuni genomes. The bird isolates from Michigan possess class D β-lactamases and multiple virulence genes and belong to seven sequence types (STs), including three novel STs. Two isolates obtained from different bird species differed by only a single core-genome SNP despite being collected on different days, while a genetically similar lineage was observed in American robins sampled a year apart. Although the bird- and human-derived strains cluster within a core gene phylogeny, they differ by >4,000 core-genome SNPs. Relative to 1,286 genomes, Michigan bird isolates do not form a single cluster but are distributed throughout the core gene multilocus sequence typing tree. Analysis of shared STs identified genomes from dogs, water, chickens and human clinical infections that differ from Michigan bird isolates by only 10-38 core-genome SNPs. These findings demonstrate that Michigan birds harbour diverse C. jejuni lineages, with some belonging to widely distributed genotypes that are related to isolates from different bird species, host types and geographic locations. Although the substantial genomic separation between Michigan bird and human isolates indicates that they are not related, they were collected during different time periods and geographic locations, thereby limiting our ability to make comparisons. Improving understanding of the diversity, host range and transmission dynamics of wildlife-associated C. jejuni lineages is critical for strengthening source attribution studies and guiding food safety policy in agroecosystems.

PMID:42909482 | DOI:10.1099/mgen.0.001868

Front Plant Sci. 2026 Oct 5;17:1935720. doi: 10.3389/fpls.2026.1935720. eCollection 2026.

ABSTRACT

Winter wheat is grown worldwide primarily for grain, yet it also serves as an important cool-season forage, supporting livestock production when other feed is scarce. Wheat can be utilized as grazed pasture or harvested as hay, silage, and straw, and is widely used as dual-purpose (forage + grain) and double-cropping systems. During vegetative growth, wheat forage is highly palatable and nutritive, typically containing 20-30% crude protein (CP), and >80% digestibility, supporting rapid liveweight gains in beef cattle. However, forage quality is highly dynamic: as wheat matures, CP and energy decline, while neutral detergent fiber (NDF), acid detergent fiber (ADF), and lignin increase, reducing intake potential and digestibility. Forage quality is also affected by moisture, fertilization, and wheat class. At comparable developmental stages, winter and spring wheat generally show little inherent differences in forage quality, indicating that maturity and management are the major determinants of quality. This review synthesizes current knowledge on wheat forage in dual-purpose and grazing systems, emphasizing dry matter, CP, NDF, ADF, acid detergent lignin, relative feed value, and relative forage quality as key indicators of biomass, nutritive value, intake potential, and digestibility. We further assess developmental shifts in these traits and their consequences on livestock intake, animal performance, and grazing management, together with forage evaluation methods such as near-infrared reflectance spectroscopy. We also examine genetic and genomic approaches for improving forage traits. Wheat breeding has historically prioritized grain yield and straw characteristics, genomic dissection of forage quality remains limited. Nevertheless, recent genome-wide association, QTL mapping, and genomic selection studies targeting water-soluble carbohydrates, fiber fractions, and digestibility-related traits highlight promising avenues for improvement. Overall, wheat forage can provide exceptionally valuable winter feed resources, but its quality is governed by strong developmental, environmental, and genetic effects. Improved screening methods and breeding targets, such as combining high protein and energy with agronomic resilience, are needed to exploit wheat’s dual-purpose potential. This review integrates agronomic, animal nutrition, and genetic perspectives to guide future research and breeding of high-quality forage wheat.

PMID:42899183 | PMC:PMC13679537 | DOI:10.3389/fpls.2026.1935720