Related Publications

Plants (Basel). 2026 Jun 30;15(13):2025. doi: 10.3390/plants15132025.

ABSTRACT

Premature leaf senescence during the late growth stage of Arachis hypogaea (peanut) reduces photosynthetic capacity and restricts pod filling, thereby limiting yield. Although biochar has been widely used for soil improvement due to its porous structure and stability, its long-term effects on sustaining photosynthetic performance and improving yield through nutrient regulation remain insufficiently understood. Based on a long-term field micro-plot experiment established in 2009, four fertilization treatments were evaluated: maize straw return + NPK (CS), pig manure compost + NPK (PMC), biochar + NPK (BIO), and biochar-based fertilizer (BF), with three replicates. Peanut was used as the test crop in 2024. Photosynthetic parameters, SPAD values, leaf N, P, and K contents, nutrient use efficiencies (PNUE, PPUE, PKUE), nutrient ratios, carbon allocation characteristics, and yield were measured at key growth stages. Results showed that the BIO treatment maintained higher net photosynthetic rate and SPAD value at the full-pod maturity stage compared with CS, PMC, and BF. Leaf K content was significantly increased under BIO, while the N:K ratio remained below 2.1, indicating reduced risk of potassium-related nutrient imbalance. The N:P ratio also remained relatively stable, suggesting improved nutrient balance with respect to phosphorus during the late growth stage. BIO showed the highest estimated contribution of photosynthetic carbon to pod dry weight, and yield increased by 19.2-28.6% compared with other treatments. These results indicate that long-term biochar application was associated with sustained late-stage photosynthetic performance and improved leaf nutrient balance, which may contribute to higher peanut yield. This study provides new evidence supporting the potential role of long-term biochar application in sustainable peanut production.

PMID:42452231 | DOI:10.3390/plants15132025

BMC Plant Biol. 2026 Jul 14. doi: 10.1186/s12870-026-09515-5. Online ahead of print.

ABSTRACT

BACKGROUND: Peanut (Arachis hypogaea L.) is an important oilseed crop whose yield is threatened by various abiotic stresses. Glycosyltransferases are crucial for diverse plant functions, including the regulation of plant growth and development, biotic and abiotic stress response, and the biosynthesis of secondary metabolites. However, the mechanism of glycosyltransferases relates to abiotic stresses remains unclear in peanut.

RESULTS: In this study, we isolated a novel gene, AhIRX7, from a salt-tolerant mutant of peanut. The expression of AhIRX7 was strongly induced by NaCl and PEG6000. Overexpression of AhIRX7 led to increased, whereas silenced of AhIRX7 resulted in decreased tolerance of peanut seedlings to salt and drought stresses. Compared to wild-type (WT), the overexpression lines showed significantly increased chlorophyll fluorescence parameters and reduced photodamage under salt and drought stress. Their activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) were markedly enhanced, while the accumulation of superoxide anion (O^2-), hydrogen peroxide (H₂O₂) and malondialdehyde (MDA) were significantly reduced. In contrast, AhIRX7-silenced lines exhibited opposite trends in SOD, POD, and CAT activities, as well as MDA accumulation. Consequently, overexpression of AhIRX7 improved the regulation of photosynthesis, the dynamics of stomatal opening and closing under salt and drought stress in Arabidopsis plants.

CONCLUSIONS: Overall, this study indicated that AhIRX7 gene functions in enhancing drought and salt stresses in peanuts and Arabidopsis, which may serve as a candidate gene for use in improving abiotic stress resistance in crops.

PMID:42449233 | DOI:10.1186/s12870-026-09515-5

Ecotoxicol Environ Saf. 2026 Jul 13;322:120498. doi: 10.1016/j.ecoenv.2026.120498. Online ahead of print.

ABSTRACT

Microplastics (MPs) and antibiotics represent escalating emerging contaminants in global agricultural soils, posing substantial threats to crop health and ecosystem functionality worldwide. However, a comprehensive understanding of their joint toxicity and the underlying rhizosphere mechanisms under co-contamination remains elusive, leaving a critical knowledge gap. This study conducted a pot experiment using the globally cultivated peanut (Arachis hypogaea) exposed to polystyrene (PS) or polylactic acid (PLA) MPs (0.25 and 2% w/w) and oxytetracycline (OTC, 10 mg·kg⁻¹), integrating metagenomic sequencing and untargeted metabolomics to elucidate root-zone microecological responses. High-concentration co-exposures significantly suppressed peanut shoot biomass, and OTC was identified as the primary contributor to reduced leaf catalase activity (CAT) (p < 0.01). Metagenomic profiling revealed that co-exposure significantly reshaped the rhizosphere microbiota (R² = 0.939, p = 0.001), enriching Pseudomonadota while inhibiting Actinobacteriota. Untargeted metabolomics detected 3789 metabolites, revealing that co-exposure significantly regulated the accumulation of defensive flavonoids (taxifolin and daidzin) and stress-responsive steroids (ponasterone A). Particularly, the combined exposure of PLA MPs and OTC induced the most severe metabolic disruption in the rhizosphere, generating 374 differential metabolites compared to the PLA-alone treatment. Procrustes analysis confirmed a tight coupling between microbial communities and metabolomes (M² = 0.619, p = 0.004). Network analysis further identified key regulatory nodes (Nocardioides and taxifolin) that bridge the associations between the rhizosphere microenvironment and plant growth traits. This study demonstrates that microbial shifts and metabolic adjustments are essential in mediating plant responses to multi-pollutant stress, providing crucial theoretical and mechanistic insights for global agricultural environmental risk assessment under co-contamination scenarios.

PMID:42442278 | DOI:10.1016/j.ecoenv.2026.120498

Plant Physiol. 2026 Jul 2;201(3):kiag326. doi: 10.1093/plphys/kiag326.

ABSTRACT

An exquisite symbiotic relationship between legumes and rhizobia leads to the development of nitrogen-fixing specialized organs, known as nodules, in nitrate-deficient environments. By contrast, a high level of soil nitrate negatively regulates the pleiotropic phases of root nodule symbiosis (RNS), including rhizobial infection, nodule organogenesis, and leghemoglobin synthesis. Here, we identified a special group of nodule-specific nonsymbiotic leghemoglobin genes (AhLghs) in the crack-entry legume peanut and investigated their functional role and transcriptional regulation. A comparative transcriptomic analysis revealed that the downregulation of nodule inception (AhNIN) and nonsymbiotic leghemoglobin (AhLghs) genes plays a pivotal role in the nitrate-mediated inhibition of RNS in peanut. Knockdown of AhLghs and overexpression of AhLgh1 resulted in lower and higher leghemoglobin content, respectively, corroborating their roles as positive regulators of nitrogen fixation. Knockdown of AhNINs not only inhibited root nodulation but also decreased leghemoglobin content in peanut. Further, DNA-affinity purification sequencing (DAP-seq) analysis identified various nodulation genes, including AhLghs, as targets of AhNINs. Following the validation of DNA-protein interactions via electrophoretic mobility shift assay, transactivation assays revealed that AhNINs positively regulate AhLgh1 after binding to the NIN RESPONSIVE CIS ELEMENT (NRCE) of its promoter. Our work bridges a critical gap in understanding how nitrate influences nonsymbiotic leghemoglobin expression by targeting rhizobia-induced NINs in peanut and offers a potential model suggesting that the nitrate-NIN-Lgh module might represent a key evolutionary event in fine-tuning root nodulation.

PMID:42430218 | DOI:10.1093/plphys/kiag326

G3 (Bethesda). 2026 Jul 8:jkag175. doi: 10.1093/g3journal/jkag175. Online ahead of print.

ABSTRACT

The Runner-type peanut (Arachis hypogaea L.) cultivar 'Tifguard' carries an introgressed chromosomal segment on chromosome A09 from A. cardenasii that confers resistance to root-knot nematode (RKN). Despite this, a proportion of 'Tifguard' plants show RKN symptoms, which could plausibly be attributed to seed mixture or outcrossing. However, recent work has shown that cultivated peanut exhibits surprisingly frequent large-scale chromosomal instability (1-5%), raising the possibility that resistance loss could arise from spontaneous structural genomic change. To test these possibilities, we grew foundation seed in an RKN-infested field and collected symptomatic and asymptomatic plants. Lineages derived by single-seed descent were genotyped using the Axiom Arachis 48K SNP array v2 and whole-genome sequencing. Symptomatic lineages lacked the A. cardenasii introgression on chromosome A09 and instead carried the complete endogenous A. hypogaea A09 region at the expected dosage. There was no evidence of large-scale homoeologous exchange, deletion, or other genomic instability affecting this chromosome. Most susceptible plants were closely related to resistant 'Tifguard' but lacked the A09 introgression, with a smaller proportion assignable to known nematode-susceptible cultivars, implicating seed mixture with a possible contribution from cross-pollination rather than genomic instability. Because resistance depends on a single major-effect segment, rare events have disproportionate phenotypic impact, placing high demands on genetic purity. For important traits conferred by major loci, marker-based testing across seed-increase stages could verify trait retention directly, and is increasingly practical as marker costs decline.

PMID:42417136 | DOI:10.1093/g3journal/jkag175

Plant Dis. 2026 Jul 6. doi: 10.1094/PDIS-02-26-0339-RE. Online ahead of print.

ABSTRACT

Tomato spotted wilt virus (TSWV) and late leaf spot (LLS) are among the major constraints to peanut production. Cultivated peanut has narrow genetic bases and lacks strong sources of resistance. Wild species, on the other hand, harbor diverse and strong resistances to multiple pathogens. In this study, we evaluated advanced breeding lines carrying introgressions from multiple wild Arachis species (A. stenosperma, A. batizocoi, A. valida, and A. cardenasii) across three contrasting field environments and experimental designs in Georgia, USA using complementary incidence- and severity-based phenotyping. Genotype effects were highly significant for both diseases. Several wild-derived lines -particularly those from A. stenosperma ancestry- showed strong and stable TSWV resistance across environments. Interestingly, some lines lacking detectable wild segments also showed high resistance to TSWV, suggesting cryptic or undetected introgressions. LLS resistance was primarily associated with the characteristic A. cardenasii segments on A02 and A03, and lines stacking these introgressions consistently outperformed both cultivated parents and Georgia-06G, the most popular cultivar in the USA. Correlations between TSWV and LLS responses were weak, confirming genetic independence and emphasizing the need to screen both traits. A small subset of lines combined resistance to both diseases, and many also retained resistance loci to root-knot nematode (RKN), expanding their value as multi-trait donors. These findings demonstrate the power of wild introgression breeding for enhancing disease resistance and provide a foundation for deploying stacked alleles through marker-assisted and multi-environment selection.

PMID:42410685 | DOI:10.1094/PDIS-02-26-0339-RE

Zootaxa. 2026 Mar 25;5782(3):581-590. doi: 10.11646/zootaxa.5782.3.10.

ABSTRACT

The present paper presents the results of surveys of groundnut (Arachis hypogaea L.) cultivations in India with respect to Sericinae of Scarabaeidae (Coleoptera). Two new species of Sericini are described: Neosericatelangana Jayashree, Sreedevi & Ahrens, sp. nov. and Maladera rampurensis Jayashree, Sreedevi & Ahrens, sp. nov. Additionally, new records of known species are given including first state records for eight species of Sericini from Telangana and three species from Andhra Pradesh. The habitus and genitalia of the new species are furnished with detailed illustrations.

PMID:42408103 | DOI:10.11646/zootaxa.5782.3.10

Mol Breed. 2026 Jul 1;46(7):67. doi: 10.1007/s11032-026-01689-y. eCollection 2026 Jul.

ABSTRACT

The peanut seed coat serves as a vital protective layer, but the occurrence of fine cracks breaches this integrity, thereby impairing visual quality and elevating the risk of pathogen infection and postharvest mycotoxin contamination. However, knowledge on genetic factors underlying seed coat cracking (SCC) tolerance remains limited. In this study, a population of 521 recombinant inbred line (RIL) was used to identify genetic regions associated with SCC tolerance across three environments. Quantitative trait locus (QTL) mapping identified two stable QTLs on chromosomes 7 and 16, qSCCA07 and qSCCA16, explaining 3.91%-11.83% and 3.63%-7.43% of phenotypic variation, respectively. Besides, the two QTL regions were refined to 272.90 kb and 626.75 kb, respectively, by constructing a high-density genetic map using Kompetitive Allele-Specific PCR (KASP) markers. The QTL-linked markers YZ9102_chr07_1027286 and YZ9102_chr16_12140367 were validated in the RIL population and a germplasm collection. Overall, genomic regions and molecular markers reported in this study provided novel insights into the genetic basis of SCC tolerance, and basis for marker-assisted selection.

SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11032-026-01689-y.

PMID:42404757 | PMC:PMC13328760 | DOI:10.1007/s11032-026-01689-y

Mol Biol Rep. 2026 Jul 4;53(1):1098. doi: 10.1007/s11033-026-12295-8.

ABSTRACT

BACKGROUND: Soil salinity is a major abiotic stress that severely restricts peanut (Arachis hypogaea L.) growth, yield, and quality. As peanut is highly sensitive to saline-alkaline conditions, identifying transcription factors involved in salt stress tolerance is of considerable importance. Dehydration-responsive element-binding (DREB) transcription factors are known regulators of abiotic stress responses; however, their functional roles in peanut remain poorly characterized.

METHODS AND RESULTS: In this study, the AhDREB gene, encoding a DREB transcription factor, was overexpressed in peanut to investigate its regulatory function under salt stress. Transgenic T1 lines (TA1-1, TA1-6, and TA1-10) were generated via Agrobacterium-mediated transformation and verified by PCR, RT-PCR, and Western blot analyses. Under salt stress (250 mM NaCl), AhDREB transcript levels increased by 3.39-, 3.27-, and 4.06-fold in TA1-1, TA1-6, and TA1-10, respectively, compared with non-stressed controls. The downstream osmolyte biosynthetic genes AhP5CR and AhBADH were significantly upregulated, with expression increases of 2.66-3.07-fold and 2.01-4.04-fold, respectively. Consistently, proline and glycine betaine contents were markedly elevated, reaching up to 9.71- and 9.37-fold higher levels in TA1-10 plants than in controls. Among the transgenic lines, TA1-10 exhibited the highest transcriptional activity and osmolyte accumulation.

CONCLUSIONS: These results demonstrate that AhDREB enhances salt tolerance in peanut by transcriptionally activating AhP5CR and AhBADH, thereby promoting osmolyte biosynthesis and improving osmotic adjustment under saline conditions. This study provides the first functional characterization of AhDREB as a novel transcription factor regulating salt stress responses in peanut.

PMID:42400699 | DOI:10.1007/s11033-026-12295-8

RSC Adv. 2026 Jul 2. doi: 10.1039/d6ra01700b. Online ahead of print.

ABSTRACT

Next-generation energy storage systems demand advanced electrode materials that offer both high performance and long-term sustainability. Binary (MgO/SiO₂) and ternary (MgO/SiO₂/GO) nanocomposites prepared in the current work were used to investigate the suitability of these materials as electrode materials for supercapacitors with a view towards embedding biomass-derived carbon (BDC) obtained from peanut shells (Arachis hypogaea L.), which were activated using NaOH; thereby producing activated carbon (AC) of peanut shells (AC) peanut shells are renewable carbon matrices with good porosity for ion dispersion and charge storage. The ternary MgO/SiO₂/GO system exhibited both redox activity and mechanical integrity, which were investigated, and the incorporated GO offered increased surface area and electrical conductivity. Structural and morphological (XRD, SEM, FTIR spectroscopy and XPS) analyses confirmed the formation of porous nanocomposites. The ternary MgO/SiO₂/GO-AC electrode showed a better capacitive performance than that of the binary MgO/SiO₂-AC electrode when evaluated in an aqueous three-electrode configuration. Cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS) measurements were performed. The ternary composite supercapacitor electrode showed an extraordinary specific capacitance of 473 F g^-1 (scan rate at 10 mV s^-1) and a current density of 482 F g^-1 at 1 A g^-1 in a 6 M KOH electrolyte, which was higher than that of the binary nanocomposites (NCs). In addition, it revealed 94.14% capacity retention and over 95% coulombic efficiency along with an outstanding cycling stability up to 5000 GCD cycles. The MgO/SiO₂/GO electrode exhibited a high specific capacitance of 482 F g^-1 at 1 A g^-1, providing a high energy density of 67 Wh kg^-1 at a power density of 2415 W kg^-1, with good retention at higher power densities. Consequently, the MgO/SiO₂/GO-AC electrode exhibits potential for application in high-performance electrochemical supercapacitors in the near future.

PMID:42395715 | PMC:PMC13324999 | DOI:10.1039/d6ra01700b

J Ind Microbiol Biotechnol. 2026 Jan 8;53:kuag017. doi: 10.1093/jimb/kuag017.

ABSTRACT

Resveratrol is a high-value polyphenolic compound widely utilized in nutraceutical, cosmetic, and pharmaceutical applications. However, most microbial production systems rely on glucose as the primary carbon source, which limits flexibility for integrating alternative and renewable feedstocks. In this study, we developed an engineered Escherichia coli platform to investigate resveratrol biosynthesis under xylose-supporting conditions, using food-grade D-xylose as the carbon source. A heterologous pathway consisting of Populus tomentosa 4-coumarate: CoA ligase (Pt4CL) and Arachis hypogaea stilbene synthase (AhSTS) was introduced to convert externally supplied p-coumaric acid (PCA) into resveratrol. To improve precursor availability, intracellular malonyl-CoA supply was enhanced by introducing matB and matC from Streptomyces coelicolor A3(2) and overexpressing the acetyl-CoA carboxylase complex (ACC) from E. coli. Xylose assimilation was further strengthened by expressing xylE, xylA, and xylB, while carbon catabolite repression was alleviated using CRISPR interference (CRISPRi) targeting the glucose transporter gene ptsG. Under shake-flask conditions, the engineered strain produced up to 23.9 mg/L resveratrol from food-grade D-xylose, accompanied by near-complete xylose consumption and 93%-94% precursor conversion. This corresponded to an overall fermentation yield of approximately 12.5 mg resveratrol per g xylose consumed. Similar titers (27 mg/L) were obtained in a 5-L bioreactor, indicating stable pathway performance under controlled fermentation conditions. Overall, these results show that E. coli can be engineered to support efficient precursor-to-product conversion under xylose-supported conditions, providing a useful proof-of-concept framework for integrating alternative carbon sources into microbial production platforms for aromatic compounds. One sentence summary An engineered Escherichia coli system integrates xylose utilization, malonyl-CoA pathway optimization, and CRISPRi regulation to support resveratrol biosynthesis under xylose-supported conditions.

PMID:42392196 | PMC:PMC13358167 | DOI:10.1093/jimb/kuag017

Water Environ Res. 2026 Jul;98(7):e70465. doi: 10.1002/wer.70465.

ABSTRACT

In this research work, the desorption of malachite green dye from water by means of adsorption onto NaOH-activated carbon obtained from agricultural waste sources including coconut husks and peanut shells is examined. Scanning Electron Microscopy, X-Ray Diffraction, and Fourier Transform Infrared Spectroscopy were applied for activated coconut husk carbon and activated groundnut shell carbon. The activated coconut husk carbon demonstrated a remarkable removal efficiency of 95.6%, whereas the activated groundnut shell carbon exhibited a removal efficiency of 92.1% at an optimal pH of 7-8, adsorbent dosage of 0.03 g, and initial dye concentration of 20 ppm. The adsorption mechanism followed the Freundlich isotherm model with an R² value of 0.98 and 0.99 for activated coconut husk carbon and activated groundnut shell carbon. Furthermore, electrodes for groundnut and coconut shells were made, and these were then electrochemically characterized using methods such as electrochemical impedance spectroscopy, linear sweep voltage measurement, and cyclic voltammetry. Maximum dye removal of 90% was obtained at 40 min for reaction time with an initial dye concentration of 20 ppm.

PMID:42389904 | PMC:PMC13349442 | DOI:10.1002/wer.70465

BMC Plant Biol. 2026 Jun 29. doi: 10.1186/s12870-026-09283-2. Online ahead of print.

ABSTRACT

BACKGROUND: Plant architecture is a key agronomic trait of peanut (Arachis hypogaea L.), which is closely associated with yield, stress resistance, and suitability for mechanical harvesting. However, research on the genetics and gene mining of peanut plant architecture remains relatively limited, thereby hindering the genetic improvement of peanut plant architecture.

RESULTS: Most cultivated peanut varieties exhibit an erect or semi-prostrate growth habit, whereas wild peanut species predominantly display a trailing growth habit. In the present study, a recombinant inbred line (RIL) population, designated as the TI population was developed by crossing the female parent Tifrunner with the male parent IpaDur, a synthetic amphidiploid derived from cross of Arachis ipaënsis × Arachis duranensis. Traits related to plant architecture, including lateral branch angle (LBA), lateral branch length (LBL), main stem height (MSH), main stem thickness (MST), lateral branch thickness (LBT), internode length (IL), number of branches (NBS), and biomass (BIO), were evaluated across three environments. Based on a high-density genetic linkage map, 20 QTLs associated with these traits were identified, which explained 6.04%-18.68% of the phenotypic variance (PVE). A locus controlling LBA, LBL, and MST was mapped to an overlapping interval (122.57-137.18 Mb) on chromosome 14. Phenotypic effect analysis revealed that this wild species-derived segment is crucial for controlling the typical morphogenesis of wild-type peanut species. In addition, we identified a set of genotypes derived from cultivated-wild hybrid population, which exhibited the convergence of one or more favorable agronomical traits.

CONCLUSIONS: Using a cultivar-wild hybrid population, 20 QTLs for plant architecture were identified in peanut. A wild-derived genomic segment was found to control typical wild-type morphogenesis. Novel germplasm pyramiding multiple agronomic favorable traits were selected. This study provides key theoretical insights and valuable resources for utilizing wild species in peanut improvement.

PMID:42374207 | DOI:10.1186/s12870-026-09283-2

Plant Dis. 2026 Jun 26. doi: 10.1094/PDIS-03-26-0454-RE. Online ahead of print.

ABSTRACT

Venturia effusa, the causal agent of pecan scab, drives the spray program in Georgia's pecan production. Miravis Top (difenoconazole, FRAC 3 + pydiflumetofen, FRAC 7) has been widely adopted for pecan scab management in recent years due to the high efficacy of its SDHI component, pydiflumetofen. In late summer 2025, a severe outbreak occurred in a commercial orchard in South Georgia despite a well-maintained spray program that included Miravis Top. While resistance to demethylation inhibitor (DMI) fungicides and other fungicide classes in V. effusa has been well documented, resistance to pydiflumetofen has not been reported. Symptomatic leaves and nuts were collected from cultivars 'Desirable' and 'Pawnee' located on a commercial farm in Georgia. Thirty-five single-spore isolates were obtained and compared with a historic baseline population (n = 12; 1993-1994) presumed unexposed to SDHIs. In mycelial growth assays, baseline isolates showed a mean EC₅₀ of 0.012 µg/ml pydiflumetofen, whereas values from outbreak isolates ranged from reduced sensitive (0.047-0.091 µg/ml; n = 7) to moderate resistant (0.281-0.895 µg/ml; n = 10) and high resistant (1.17-6.70 µg/ml; n = 18), with resistance factors >500. Sequencing of VesdhB, VesdhC, and VesdhD genes identified six amino acid (aa) substitutions associated with reduced sensitivity: H252R (VeSdhB), K73R; M82I; N84S (VeSdhC), and D150E and D150G (VeSdhD). All moderate to high resistant isolates carried at least one substitution, except for a subset of moderate resistant isolates that exhibited the lowest EC₅₀ values within this group. The most resistant isolate (Ve25-22) carried two mutations, K73R (VeSdhC) and D150G (VeSdhD). Cross-sensitivity assays with fluopyram, isofetamid, and benzovindiflupyr showed incomplete cross-resistance with pydiflumetofen (moderate correlations), but a strong correlation between fluopyram and isofetamid (r = 0.998, P < 0.001). Notably, isolates carrying the M82I substitution in VeSdhC were high resistant to both fluopyram and isofetamid. This study provides the first evidence of reduced sensitivity to pydiflumetofen in V. effusa linked to target-site substitutions in the VeSdhB, VeSdhC, and VeSdhD subunits and highlights the importance of resistance management strategies, including monitoring pathogen populations, rotating fungicide modes of action, using fungicide mixtures, and limiting the number of applications.

PMID:42363620 | DOI:10.1094/PDIS-03-26-0454-RE

Front Plant Sci. 2026 Jun 10;17:1838203. doi: 10.3389/fpls.2026.1838203. eCollection 2026.

ABSTRACT

Peanut (Arachis hypogaea L.) is an important crop in the world, serving as a key source of edible oil and protein. Comprehensive genomic and phenotypic analyses were conducted on 87 accessions from the U.S. peanut mini-core collection using 217 Gb of high-quality resequencing data to identify the candidate genes and markers that underlie the leaf spot resistance and seed dormancy in peanuts. A total of 87,726 SNPs were identified and mapped across 20 chromosomes, revealing a higher SNP density in the B subgenome (35.55 SNPs/Mb) compared to the A subgenome (33.26 SNPs/Mb). Phylogenetic, population structure, and principal component analyses consistently partitioned the accessions into three distinct gene pools designated as Group 1, 2, and 3. Group 1, comprising primarily Arachis hypogaea, included 28 genotypes; Group 2, mainly fastigiata types, comprised 18 accessions; while Group 3, displaying the highest diversity, contained mixed genotypes from the other groups. Linkage disequilibrium analysis indicated an LD decay distance of approximately 63.1 kb, confirming that the marker density was sufficient for GWAS. Significant SNP associations at a suggestive threshold of p< 1.14 × 10^-1 were identified for leaf spot, seed germination and dormancy agronomic traits. As a result, three candidate genes were identified: Ah11g381400, homologous to Arabidopsis ATE1, was associated with early leaf spot resistance; Ah16g445600, a homolog of ERF34, was linked to late leaf spot resistance; and Ah19g214100, homologous to ICE1, emerged as a central regulator affecting both germination and dormancy. These findings provide actionable targets for marker-assisted selection to enhance disease resilience and seed quality in breeding programs.

PMID:42359412 | PMC:PMC13290452 | DOI:10.3389/fpls.2026.1838203

Plants (Basel). 2026 Jun 18;15(12):1889. doi: 10.3390/plants15121889.

ABSTRACT

Peanut (Arachis hypogaea L.) is a major oil and economic crop, yet genetic transformation remains inefficient and time-consuming, hindering functional genomics and molecular breeding. In this study, we found that the use of GRF, GIF and WOX genes improved the efficiency of Agrobacterium-mediated peanut hairy-root transformation. Here, we identified multiple peanut Growth-Regulating Factor (GRF) genes, GRF-Interacting Factor (GRF-GIF) fusion genes and WUSCHEL-related homeobox (WOX) genes, constructed high-expression vectors, and delivered them into A. rhizogenes to infect 3-5 cm peanut stem segments cut from 30-day-old seedlings. Statistical analysis of the data showed that, relative to the empty-vector control, expression of these developmental regulators markedly enhanced hairy-root growth: the number of roots per explant increased by 1.3-2.4-fold. Observations using reporter constructs showed that growth factors (besides 2S-PL-GUS and GRF-2A-T-GUS) improved the transformation efficiency of hairy roots, among which the highest transformation efficiency of GRF-2A (396)-GIF-GUS was 85.14 ± 2.94%. Collectively, these findings provide an efficient and rapid platform for the study of peanut gene function.

PMID:42357208 | PMC:PMC13306245 | DOI:10.3390/plants15121889

Plants (Basel). 2026 Jun 11;15(12):1798. doi: 10.3390/plants15121798.

ABSTRACT

Legume-rhizobium symbiosis represents a crucial biological nitrogen fixation system. The AP2/ERF transcription factor ERN1 plays a vital role in nodulation of model legumes; however, its function in peanut (Arachis hypogaea), a typical crack-entry infection legume, remains unclear. To explore this, we performed transcriptome sequencing of peanut roots at 3 days post-inoculation (dpi) with rhizobium. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses showed that differentially expressed genes (DEGs) were mainly enriched in DNA-binding transcription factor activity, plant-pathogen interaction, and plant hormone signal transduction pathways. The most strongly up-regulated gene was AhERN1, which was highly expressed in peanut roots and nodules. Subcellular localization indicated that AhERN1 was a nuclear-localized protein, and yeast transcriptional activation assays confirmed that AhERN1 functions as a transcriptional activator relying on its C-terminal domain. Furthermore, hairy root overexpression of AhERN1 significantly increased the number of peanut nodules. Collectively, these results reveal that AhERN1 acts as a positive regulator to promote rhizobium-induced nodule development in peanut, providing new insights into the regulatory mechanism of nodulation in dalbergoid legumes.

PMID:42357117 | PMC:PMC13306481 | DOI:10.3390/plants15121798

Plants (Basel). 2026 Jun 8;15(12):1768. doi: 10.3390/plants15121768.

ABSTRACT

Global warming-triggered heat stress severely restricts plant growth and crop productivity. Peanut (Arachis hypogaea L.), a vital oilseed and cash crop that is susceptible to high temperatures throughout its growth cycle, exhibits inhibited peg and pod development, growth retardation, and premature leaf senescence under heat stress, which ultimately causes substantial yield losses. Heat shock factors (Hsfs) serve as core regulatory modulators of plant abiotic stress tolerance, among which the HsfB subfamily exerts a critical function in thermotolerance modulation. Nevertheless, the biological functions of peanut HsfB genes remain largely uncharacterized. In the present study, a total of 16 HsfB subfamily members were identified from the peanut genome, possessing highly conserved gene structures and protein motifs. Phylogenetic analysis revealed that the peanut AhHsfB genes are classified into four distinct subfamilies. Chromosomal localization analysis indicated that these 16 AhHsfB genes are unevenly distributed across nine peanut chromosomes. Transcriptomic profiling demonstrated that the transcript levels of AhHsfB genes were significantly upregulated by 6- to 120-fold upon heat stress exposure. Subcellular localization and transcriptional activity assays further validated that AhHsfB1-5A is a nucleus-localized protein with intrinsic transcriptional activation activity. Ectopic overexpression of AhHsfB1-5A in Arabidopsis thaliana remarkably enhanced seed germination ability and antioxidant capacity under heat stress conditions, with a maximum 18.84% increase in green seedling rate. This study systematically characterizes the HsfB subfamily in peanut and elucidates the positive regulatory role of AhHsfB1-5A in plant thermotolerance. These findings deepen our understanding of the role of HsfB and provide valuable genetic resources for molecular breeding of heat-resistant peanut varieties.

PMID:42357087 | PMC:PMC13307298 | DOI:10.3390/plants15121768

Ying Yong Sheng Tai Xue Bao. 2026 May;37(5):1477-1487. doi: 10.13287/j.1001-9332.202605.009.

ABSTRACT

We conducted a field experiment to investigate the effects of biochar derived from three feedstocks (pig manure, peanut shell, and maize straw) on the nutrient limitation status of soil microbial communities and the abundance of functional genes involved in organic carbon degradation in a Phyllostachys edulis forest. Each biochar was applied at a rate of 20 t·hm^-2, with soil without biochar amendment as control. We measured soil and microbial properties after two years. The results showed that all biochar types significantly increased soil pH, soil organic carbon, total phosphorus, and available phosphorus contents. Pig manure biochar significantly reduced soil C:P and alleviated the stoichiometric imbalance between microbial biomass and soil resources. All biochar treatments significantly increased β-glucosidase activity (by 46.5%-131.1%) but decreased the activities of β-N-acetylglucosaminidase (by 20.6%-51.1%) and acid phosphatase (by 23.1%-56.4%). Biochar application significantly intensified microbial carbon limitation while reduced phosphorus limitation and decreased microbial carbon use efficiency, with the most pronounced reduction being observed under pig manure biochar. Biochar application significantly increased the abundances of functional genes of starch, hemicellulose, cellulose, pectin and lignin degradation, following the order of pig manure biochar > peanut shell biochar > maize straw biochar. Random forest analysis indicated that soil total phosphorus and available phosphorus contents were the key factors influencing microbial carbon limitation. Partial least squares path modeling (PLS-PM) indicated that biochar inputs increased microbial carbon limitation by elevating soil pH and alleviating the C:P imbalance, which in turn reduced carbon use efficiency. The degree of microbial carbon limitation exhibited a significant positive effect on the abundance of micro-bial carbon degradation functional genes. In conclusion, biochar from different feedstocks could regulate microbial nutrient limitation by altering soil pH and nutrient stoichiometric balance, thereby affecting microbial carbon metabolic efficiency.

PMID:42350124 | DOI:10.13287/j.1001-9332.202605.009

N Engl J Med. 2026 Jun 25;394(24):2449-2458. doi: 10.1056/NEJMcp2314424.

ABSTRACT

Early introduction of peanut protein reduces allergy prevalence by approximately 80%, with efficacy diminishing as introduction is delayed. Appropriate prevention involves ingestion of approximately 2 g of peanut protein weekly for infants at low risk and 4 to 6 g weekly for infants at high risk. Population-level implementation that targets all infants achieves greater reduction in disease burden than approaches that target only high-risk groups, although disparities exist among some ethnic groups and groups with restricted access to care. Peanut immunotherapy initiated in younger children (1 to 3 years of age) shows superior efficacy and higher rates of clinical remission as compared with immunotherapy initiated in older children. The natural history of untreated peanut allergy follows a trajectory of increasing peanut-specific IgE levels and clinical reactivity over time, underscoring the importance of early intervention during this narrow developmental window.

PMID:42341303 | DOI:10.1056/NEJMcp2314424