Identification of two major QTLs for pod shell thickness in peanut (Arachis hypogaea L.) using BSA-seq analysis.

BACKGROUND: Pod shell thickness (PST) is an important agronomic trait of peanut because it affects the ability of shells to resist pest infestations and pathogen attacks, while also influencing the peanut shelling process. However, very few studies have explored the genetic basis of PST. RESULTS: An F2 segregating population derived from a cross between the thick-shelled cultivar Yueyou 18 (YY18) and the thin-shelled cultivar Weihua 8 (WH8) was used to identify the quantitative trait loci (QTLs) for PST. On the basis of a bulked segregant analysis sequencing (BSA-seq), four QTLs were preliminarily mapped to chromosomes 3, 8, 13, and 18. Using the genome resequencing data of YY18 and WH8, 22 kompetitive allele-specific PCR (KASP) markers were designed for the genotyping of the F2 population. Two major QTLs (qPSTA08 and qPSTA18) were identified and finely mapped, with qPSTA08 detected on chromosome 8 (0.69-Mb physical genomic region) and qPSTA18 detected on chromosome 18 (0.15-Mb physical genomic region). Moreover, qPSTA08 and qPSTA18 explained 31.1-32.3% and 16.7-16.8% of the phenotypic variation, respectively. Fifteen genes were detected in the two candidate regions, including three genes with nonsynonymous mutations in the exon region. Two molecular markers (Tif2_A08_31713024 and Tif2_A18_7198124) that were developed for the two major QTL regions effectively distinguished between thick-shelled and thin-shelled materials. Subsequently, the two markers were validated in four F2:3 lines selected. CONCLUSIONS: The QTLs identified and molecular markers developed in this study may lay the foundation for breeding cultivars with a shell thickness suitable for mechanized peanut shelling.

Outer Sphere Electron Transfer Enabling High-Voltage Aqueous Electrolytes.

Aqueous electrolytes with a low voltage window (1.23 V) and prone side reactions, such as hydrogen evolution reaction and cathode dissolution, compromise the advantages of high safety and low cost of aqueous metal-ion batteries. Herein, introducing catechol (CAT) into the aqueous electrolyte, an outer sphere electron transfer mechanism is initiated to inhibit the water reactivity, achieving an electrochemical window of 3.24 V. In a typical Zn-ion battery, the outer sphere electrons jump from CAT to Zn2+-H2O at a geometrically favorable situation and between the solvation molecules without breaking or forming chemical bonds as that of the inner sphere electron transfers. The excited state π-π stacking further leads to the outer sphere electron transfer occurring at the electrolyte/electrode interface. This high-voltage electrolyte allows achieving an operating voltage two times higher than that of the usual aqueous electrolytes and provides almost the highest energy density and power density for the V2O5-based aqueous Zn-ion full batteries. The Zn//Zn symmetric battery delivers a 4000 h lifespan, and the Zn//V2O5 full battery achieves a ∼380 W h kg-1 energy density and a 92% capacity retention after 3000 cycles at 1 A g-1 and a 2.4 V output voltage. This outer sphere electron transfer strategy paves the way for designing high-voltage aqueous electrolytes.

Transcriptome sequencing and expression analysis in peanut reveal the potential mechanism response to Ralstonia solanacearum infection.

BACKGROUND: Bacterial wilt caused by Ralstonia solanacearum severely affects peanut (Arachis hypogaea L.) yields. The breeding of resistant cultivars is an efficient means of controlling plant diseases. Therefore, identification of resistance genes effective against bacterial wilt is a matter of urgency. The lack of a reference genome for a resistant genotype severely hinders the process of identification of resistance genes in peanut. In addition, limited information is available on disease resistance-related pathways in peanut. RESULTS: Full-length transcriptome data were used to generate wilt-resistant and -susceptible transcript pools. In total, 253,869 transcripts were retained to form a reference transcriptome for RNA-sequencing data analysis. Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis of differentially expressed genes revealed the plant-pathogen interaction pathway to be the main resistance-related pathway for peanut to prevent bacterial invasion and calcium plays an important role in this pathway. Glutathione metabolism was enriched in wilt-susceptible genotypes, which would promote glutathione synthesis in the early stages of pathogen invasion. Based on our previous quantitative trait locus (QTL) mapping results, the genes arahy.V6I7WA and arahy.MXY2PU, which encode nucleotide-binding site-leucine-rich repeat receptor proteins, were indicated to be associated with resistance to bacterial wilt. CONCLUSIONS: This study identified several pathways associated with resistance to bacterial wilt and identified candidate genes for bacterial wilt resistance in a major QTL region. These findings lay a foundation for investigation of the mechanism of resistance to bacterial wilt in peanut.

Genome-wide association study and development of molecular markers for yield and quality traits in peanut (Arachis hypogaea L.).

BACKGROUND: This study aims to decipher the genetic basis governing yield components and quality attributes of peanuts, a critical aspect for advancing molecular breeding techniques. Integrating genotype re-sequencing and phenotypic evaluations of seven yield components and two grain quality traits across four distinct environments allowed for the execution of a genome-wide association study (GWAS). RESULTS: The nine phenotypic traits were all continuous and followed a normal distribution. The broad heritability ranged from 88.09 to 98.08%, and the genotype-environment interaction effects were all significant. There was a highly significant negative correlation between protein content (PC) and oil content (OC). The 10× genome re-sequencing of 199 peanut accessions yielded a total of 631,988 high-quality single nucleotide polymorphisms (SNPs), with 374 significant SNP loci identified in association with the nine traits of interest. Notably, 66 of these pertinent SNPs were detected in multiple environments, and 48 of them were linked to multiple traits of interest. Five loci situated on chromosome 16 (Chr16) exhibited pleiotropic effects on yield traits, accounting for 17.64-32.61% of the observed phenotypic variation. Two loci on Chr08 were found to be strongly associated with protein and oil contents, accounting for 12.86% and 14.06% of their respective phenotypic variations, respectively. Linkage disequilibrium (LD) block analysis of these seven loci unraveled five nonsynonymous variants, leading to the identification of one yield-related candidate gene and two quality-related candidate genes. The correlation between phenotypic variation and SNP loci in these candidate genes was validated by Kompetitive allele-specific PCR (KASP) marker analysis. CONCLUSIONS: Overall, molecular markers were developed for genetic loci associated with yield and quality traits through a GWAS investigation of 199 peanut accessions across four distinct environments. These molecular tools can aid in the development of desirable peanut germplasm with an equilibrium of yield and quality through marker-assisted breeding.

Heterostructured Graphene@Silica@Iron Phenylphosphinate for Fire-Retardant, Strong, Thermally Conductive Yet Electrically Insulated Epoxy Nanocomposites.

The portfolio of extraordinary fire retardancy, mechanical properties, dielectric/electric insulating performances, and thermal conductivity (λ) is essential for the practical applications of epoxy resin (EP) in high-end industries. To date, it remains a great challenge to achieve such a performanceportfolio in EP due to their different and even mutually exclusive governing mechanisms. Herein, a multifunctional additive (G@SiO2@FeHP) is fabricated by in situ immobilization of silica (SiO2) and iron phenylphosphinate (FeHP) onto the graphene (G) surface. Benefiting from the synergistic effect of G, SiO2 and FeHP, the addition of 1.0 wt% G@SiO2@FeHP enables EP to achieve a vertical burning (UL-94) V-0 rating and a limiting oxygen index (LOI) of 30.5%. Besides, both heat release and smoke generation of as-prepared EP nanocomposite are significantly suppressed due to the condensed-phase function of G@SiO2@FeHP. Adding 1.0 wt% G@SiO2@FeHP also brings about 44.5%, 61.1%, and 42.3% enhancements in the tensile strength, tensile modulus, and impact strength of EP nanocomposite. Moreover, the EP nanocomposite exhibits well-preserved dielectric and electric insulating properties and significantly enhanced λ. This work provides an integrated strategy for the development of multifunctional EP materials, thus facilitating their high-performance applications.

Rational prediction of immunogenicity clustering through cross-reactivity analysis of thirteen SARS-CoV-2 variants.

SARS-CoV-2 breakthrough infections in vaccinated individuals underscore the threat posed by continuous mutating variants, such as Omicron, to vaccine-induced immunity. This necessitates the search for broad-spectrum immunogens capable of countering infections from such variants. This study evaluates the immunogenicity relationship among SARS-CoV-2 variants, from D614G to XBB, through Guinea pig vaccination, covering D614G, Alpha, Beta, Gamma, Delta, BA.1, BA.2, BA.2.75, BA.2.75.2, BA.5, BF.7, BQ.1.1, and XBB, employing three immunization strategies: three-dose monovalent immunogens, three-dose bivalent immunogens, and a two-dose vaccination with D614G followed by a booster immunization with a variant strain immunogen. Three distinct immunogenicity clusters were identified: D614G, Alpha, Beta, Gamma, and Delta as cluster 1, BA.1, BA.2, and BA.2.75 as cluster 2, BA.2.75.2, BA.5, BF.7, BQ.1.1, and XBB as cluster 3. Broad-spectrum protection could be achieved through a combined immunization strategy using bivalent immunogens or D614G and XBB, or two initial D614G vaccinations followed by two XBB boosters. A comparison of neutralizing antibody levels induced by XBB boosting and equivalent dosing of D614G and XBB revealed that the XBB booster produced higher antibody levels. The study suggests that vaccine antigen selection should focus on the antigenic alterations among variants, eliminating the need for updating vaccine components for each variant.

Solanum nigrum L. berries extract ameliorated the alcoholic liver injury by regulating gut microbiota, lipid metabolism, inflammation, and oxidative stress.

Solanum nigrum L. (SN) berry is an edible berry containing abundant polyphenols and bioactive compounds, which possess antioxidant and antiinflammatory properties. However, the effects of SN on alcohol-induced biochemical changes in the enterohepatic axis remain unclear. In the current study, a chronic ethanol-fed mice ALD model was used to test the protective mechanisms of SN berries. Microbiota composition was determined via 16S rRNA sequencing, we found that SN berries extract (SNE) improved intestinal imbalance by reducing the Firmicutes to Bacteroides ratio, restoring the abundance of Akkermansia microbiota, and reducing the abundance of Allobaculum and Shigella. SNE restored the intestinal short-chain fatty acids content. In addition, liver transcriptome data analysis revealed that SNE primarily affected the genes involved in lipid metabolism and inflammatory responses. Furthermore, SNE ameliorated hepatic steatosis in alcohol-fed mice by activating AMP-activated protein kinase (AMPK), acetyl-CoA carboxylase (ACC), peroxisome proliferator-activated receptor α (PPAR-α). SNE reduced the expression of toll-like receptor 4 (TLR4), myeloid differentiation factor-88 (MyD88) nuclear factor kappa-B (NF-κB), which can indicate that SNE mainly adjusted LPS/TLR4/MyD88/NF-κB pathway to reduce liver inflammation. SNE enhanced hepatic antioxidant capacity by regulating NRF2-related protein expression. SNE alleviates alcoholic liver injury by regulating of gut microbiota, lipid metabolism, inflammation, and oxidative stress. This study may provide a reference for the development and utilization of SN resources.

3D printing MXene-based electrodes for supercapacitors.

3D printing, as an advanced and promising strategy for processing electrode for energy storage devices, such as supercapacitors and batteries, has garnered considerable interest in recent decades. The interest in 3D printed electrodes stems from its exceptional performance and manufacturing features, including customized sizes and shapes and the layer-by-layer processing principle, etc., especially integrating with MXene which allows the manufacturing of electrodes from different raw materials and possessing desired electrochemical properties. Herculean challenges, such as material compatibility of the printing inks, nondurable interfacial or bulk mechanical strength of the printed electrodes, and sometimes the low capacitance, lead to inferior electrochemical performance and hinder the practical applications of this promising technology. In this review, we firstly summarize the representative 3D printing methods, then, review the MXene-based 3D printing electrodes made from different materials, and last, provide electrochemical performance of 3D printing MXene-based electrodes for supercapacitors. Furthermore, based on a summary on the recent progress, an outlook on these promising electrodes for sustainable energy devices is provided. We anticipate that this review could provide some insights into overcoming the challenges and achieving more remarkable electrochemical performance of 3D printing supercapacitor electrodes and offer perspectives in the future for emerging energy devices.

Zn-ion ultrafluidity via bioinspired ion channel for ultralong lifespan Zn-ion battery.

Rechargeable aqueous Zn-ion batteries have been deemed a promising energy storage device. However, the dendrite growth and side reactions have hindered their practical application. Herein, inspired by the ultrafluidic and K+ ion-sieving flux through enzyme-gated potassium channels (KcsA) in biological plasma membranes, a metal-organic-framework (MOF-5) grafted with -ClO4 groups (MOF-ClO4) as functional enzymes is fabricated to mimic the ultrafluidic lipid-bilayer structure for gating Zn2+ 'on' and anions 'off' states. The MOF-ClO4 achieved perfect Zn2+/SO4 2- selectivity (∼10), enhanced Zn2+ transfer number ([Formula: see text]) and the ultrafluidic Zn2+ flux (1.9 × 10-3 vs. 1.67 mmol m-2 s-1 for KcsA). The symmetric cells based on MOF-ClO4 achieve a lifespan of over 5400 h at 10 mA cm-2/20 mAh cm-2. Specifically, the performance of the PMCl-Zn//V2O5 pouch cell keeps 81% capacity after 2000 cycles at 1 A g-1. The regulated ion transport, by learning from a biological plasma membrane, opens a new avenue towards ultralong lifespan aqueous batteries.

Genome-Wide Association Studies of Embryogenic Callus Induction Rate in Peanut (Arachis hypogaea L.).

The capability of embryogenic callus induction is a prerequisite for in vitro plant regeneration. However, embryogenic callus induction is strongly genotype-dependent, thus hindering the development of in vitro plant genetic engineering technology. In this study, to examine the genetic variation in embryogenic callus induction rate (CIR) in peanut (Arachis hypogaea L.) at the seventh, eighth, and ninth subcultures (T7, T8, and T9, respectively), we performed genome-wide association studies (GWAS) for CIR in a population of 353 peanut accessions. The coefficient of variation of CIR among the genotypes was high in the T7, T8, and T9 subcultures (33.06%, 34.18%, and 35.54%, respectively), and the average CIR ranged from 1.58 to 1.66. A total of 53 significant single-nucleotide polymorphisms (SNPs) were detected (based on the threshold value -log10(p) = 4.5). Among these SNPs, SNPB03-83801701 showed high phenotypic variance and neared a gene that encodes a peroxisomal ABC transporter 1. SNPA05-94095749, representing a nonsynonymous mutation, was located in the Arahy.MIX90M locus (encoding an auxin response factor 19 protein) at T8, which was associated with callus formation. These results provide guidance for future elucidation of the regulatory mechanism of embryogenic callus induction in peanut.

Chloroplast and whole-genome sequencing shed light on the evolutionary history and phenotypic diversification of peanuts.

Cultivated peanut (Arachis hypogaea L.) is a widely grown oilseed crop worldwide; however, the events leading to its origin and diversification are not fully understood. Here by combining chloroplast and whole-genome sequence data from a large germplasm collection, we show that the two subspecies of A. hypogaea (hypogaea and fastigiata) likely arose from distinct allopolyploidization and domestication events. Peanut genetic clusters were then differentiated in relation to dissemination routes and breeding efforts. A combination of linkage mapping and genome-wide association studies allowed us to characterize genes and genomic regions related to main peanut morpho-agronomic traits, namely flowering pattern, inner tegument color, growth habit, pod/seed weight and oil content. Together, our findings shed light on the evolutionary history and phenotypic diversification of peanuts and might be of broad interest to plant breeders.

[Spatial differentiation and mechanism of carbon source/sink of forest swamps in riverside of Changbai Mountains, China]. / 长白山河滨森林湿地碳源/汇空间分异规律及机制.

To quantify the carbon source/sink function of riparian zone swamps and explore the feedback relationship with climate change, we measured the annual fluxes of soil greenhouse gas, soil carbon emission, net vegetation carbon sequestration and related environmental factors (temperature, water level, etc.) by static chamber-gas chromatography and relative growth equation methods in three kinds of forest swamps (Alnus sibirica swamp, Betula platyphylla swamp, and Larix olgensis swamp) distributed along the water reduction gradient of lowland to highland in the stream riparian zone of Changbai Mountains. The results showed that the annual fluxes of CH4(0.19-0.85 mg·m-2·h-1), CO2(60.81-228.63 mg·m-2·h-1), and N2O (-0.02-0.05 mg·m-2·h-1) showed spatial variations along the water gradient of lowland to highland, with a trend of first constant then decreasing, decreasing, and first absorption then emission, respectively. The spatial variations of annual fluxes of these greenhouse gases were controlled by water levels. The annual net carbon sequestration of vegetation (2.61-3.45 t C·hm-2·a-1) was constant along the water gradient, which was mainly promoted by nitrate nitrogen content. The carbon source/sink and global warming potential (GWP) undergo regular changes along water gradients. The A. sibirica swamp was a carbon sink (1.93 t C·hm-2·a-1), the B. platyphylla swamp was a weak carbon source (-0.18 t C·hm-2·a-1), and the L. olgensis swamp was a strong carbon source (-2.51 t C·hm-2·a-1). The spatial variation of carbon source/sink in forest swamps was jointly promoted by water level and nitrate nitrogen content. A. sibirica swamp exhibited a strong cooling effect with a strong negative feedback effect on climate change (-5.88 t CO2·hm-2·a-1). L. olgensis swamp exhibited a strong warming effect with a strong positive feedback effect (10.97 t CO2·hm-2·a-1). B. platyphylla swamp exhibited a weak warming effect, approximately neutral (2.95 t CO2·hm-2·a-1). The spatial variation of GWP in forest swamps was mainly inhibited by water level.