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SUMMARY: ROS/redox signaling plays an important role in the regulation of signal transduction and acclimation pathways activated by multiple abiotic stresses and leaf senescence. However, the regulatory events that produce ROS under different stimuli are far from clear. Here, we report the elucidation of the molecular mechanism of an h type thioredoxin, AhTRX h2, positively regulates Al sensitivity and leaf senescence by promoting ROS. AhTRX h2 transcript levels increased greatly during both natural senescence and Al stress condition in peanut. Ectopic expression of AhTRX h2 in Arabidopsis conferred Al sensitivity as well as premature leaf senescence, manifested by multiple indices, including inhibiting root elongation, severe cell death, and accelerated expression of MC1 and CEX17. AhTRX h2 exhibited similar functions to AtTRX h2, as AhTRX h2 was able to restore the phenotypes of the AtTRX h2 defective mutant (trxh2‐4) which showed Al tolerant and late senescence phenotypes. The knock down of AhTRX h2 markedly suppressed Al‐ and senescence‐induced cell death in peanut. AhTRX h2 could recruit catalytic subunit of protein phosphatase 2A (PP2AC2) to form a stable complex. The interaction between AhTRX h2 and AtPP2AC2, as well as AhPP2AC2 and AtTRX h2 was also proved. Overexpression of AhPP2AC2 significantly enhanced Al sensitivity and leaf senescence in Arabidopsis. Protein stability assay revealed that AhTRX h2 was more stable during aging or aluminum stress. Moreover, PP2AC2 could greatly enhance the stability of AhTRX h2 in vivo. Consistent with these observations, overexpression of AhPP2AC2 effectively enhanced AhTRX h2‐induced Al sensitivity and precocious leaf senescence. AhTRX h2 and AhPP2AC2 required ABA and ROS in response to cell death under Al stress and senescence, and it was evidence to suggest that ABA acted upstream of ROS in this process. Together, AhTRX h2 and AhPP2AC2 constitute a stable complex that promotes the accumulation of ABA and ROS, effectively regulate cell death. These findings suggest that TRX h2‐PP2AC2‐mediated pathway may be a widespread mechanism in regulating Al stress and leaf senescence. Siginficance Statement: AhTRX h2 and AhPP2AC2 constitute a stable complex that promotes the accumulation of ABA and ROS, effectively regulate cell death. TRX h2‐PP2AC2‐mediated pathway may be a widespread mechanism in regulating Al stress and leaf senescence. [ABSTRACT FROM AUTHOR]

Introduction: Trehalose is vital for plant metabolism, growth, and stress resilience, relying on Trehalose-6-phosphate synthase (TPS) and Trehalose-6- phosphate phosphatase (TPP) genes. Research on these genes in cultivated peanuts (Arachis hypogaea) is limited. Methods: This study employed bioinformatics to identify and analyze AhTPS and AhTPP genes in cultivated peanuts, with subsequent experimental validation of AhTPS9's role in cold tolerance. Results: In the cultivated peanut genome, a total of 16 AhTPS and 17 AhTPP genes were identified. AhTPS and AhTPP genes were observed in phylogenetic analysis, closely related to wild diploid peanuts, respectively. The evolutionary patterns of AhTPS and AhTPP genes were predominantly characterized by gene segmental duplication events and robust purifying selection. A variety of hormone-responsive and stress-related cis-elements were unveiled in our analysis of cis-regulatory elements. Distinct expression patterns of AhTPS and AhTPP genes across different peanut tissues, developmental stages, and treatments were revealed, suggesting potential roles in growth, development, and stress responses. Under low-temperature stress, qPCR results showcased upregulation in AhTPS genes (AhTPS2-5, AhTPS9-12, AhTPS14, AhTPS15) and AhTPP genes (AhTPP1, AhTPP6, AhTPP11, AhTPP13). Furthermore, AhTPS9, exhibiting the most significant expression difference under cold stress, was obviously induced by cold stress in cultivated peanut, and AhTPS9- overexpression improved the cold tolerance of Arabidopsis by protect the photosynthetic system of plants, and regulates sugar-related metabolites and genes. Discussion: This comprehensive study lays the groundwork for understanding the roles of AhTPS and AhTPP gene families in trehalose regulation within cultivated peanuts and provides valuable insights into the mechanisms related to cold stress tolerance. [ABSTRACT FROM AUTHOR]

Plant trehalose has been regarded to play a key role in various biological processes during the growth and development stages. Trehalose-6-phosphate synthase (TPS) and trehalose-6-phosphate phosphatase (TPP) are two important enzymes for the synthesis of plant trehalose. Up till now, the TPS and TPP gene families have been identified and characterized in numerous higher plant species, but are rarely recorded in peanuts (Arachis hypogaea). In this study, a comprehensive search was performed to identify all putative TPS and TPP proteins in the peanut genome using Arabidopsis TPS and TPP proteins as queries. We then analyzed the characteristics of TPS and TPP members, including physic-chemical parameters, subcellular localization, phylogeny relationships, gene duplication, and expression patterns by various computational tools. As a result, a total of 17 ArahyTPS and 15 ArahyTPP genes were identified and annotated in the peanut genome, which was expanded by segmental duplication events. Our Neighbor-Joining based phylogenetic tree indicated that the ArahyTPS and ArahyTPP proteins could be categorized into three and two major branches. Gene structures and protein features analysis exhibited that the ArahyTPS and ArahyTPP proteins shared high structural and functional similarities. Based on previous RNA-Seq datasets, a majority of the ArahyTPS and ArahyTPP genes were found to specifically express in at least one major organ/tissue during the growth and development. This work will not only lead to a solid foundation on reveal the potential roles of ArahyTPS and ArahyTPP gene families in peanuts but also provide evidence to related trehalose research in other higher plant species. [ABSTRACT FROM AUTHOR]

Introduction: The TGA transcription factors, plays a crucial role in regulating gene expression. In cultivated peanut (Arachis hypogaea), which faces abiotic stress challenges, understanding the role of TGAs is important. Methods: In this study, we conducted a comprehensive in analysis of the TGA gene family in peanut to elucidate their regulatory mechanisms and expression patterns under abiotic stress and hormone treatments. Furthermore, functional studies on the representative AhTGA gene in peanut cultivars were conducted using transgenic Arabidopsis and soybean hair roots. Results: The genome-wide analysis revealed that a total of 20 AhTGA genes were identified and classified into five subfamilies. Collinearity analysis revealed that AhTGA genes lack tandem duplication, and their amplification in the cultivated peanut genome primarily relies on the whole-genome duplication of the diploid wild peanut to form tetraploid cultivated peanut, as well as segment duplication between the A and B subgenomes. Promoter and Protein-protein interaction analysis identified a wide range of cis-acting elements and potential interacting proteins associated with growth and development, hormones, and stress responses. Expression patterns of AhTGA genes in different tissues, under abiotic stress conditions for low temperature and drought, and in response to hormonal stimuli revealed that seven AhTGA genes from groups I (AhTGA04, AhTGA14 and AhTGA20) and II (AhTGA07, AhTGA11, AhTGA16 and AhTGA18) are involved in the response to abiotic stress and hormonal stimuli. The hormone treatment results indicate that these AhTGA genes primarily respond to the regulation of jasmonic acid and salicylic acid. Overexpressing AhTGA11 in Arabidopsis enhances resistance to cold and drought stress by increasing antioxidant activities and altering endogenous hormone levels, particularly ABA, SA and JA. Discussion: The AhTGA genes plays a crucial role in hormone regulation and stress response during peanut growth and development. The findings provide insights into peanut's abiotic stress tolerance mechanisms and pave the way for future functional studies. [ABSTRACT FROM AUTHOR]

The pollen receptor-like protein kinase (PRK) family, an LRR receptor-like protein kinase, not only plays a role in pollen development and fertilization, but also plays a role in stress response. Based on the analysis of transcriptome data that generated in our previous study, we found that AhPRK4 was an aluminum-responsive gene. To explore the role of AhPRK4 in response to aluminum stress, we analyzed the expression of AhPRK4 by qRT-PCR in ‘ZH2’ (Al-sensitive) and ‘99-1507’ (Al-tolerant), clarified the protein structure and genetic relationship of AhPRK4 by sequence analysis, phylogenetic tree construction and other genetic analysis, constructed the recombinant plasmid by homologous recombination, obtained the intracellular domain recombinant protein of AhPRK4 by prokaryotic expression technology and determined the activity of the recombinant protein by incubation with phosphorylated antibodys. The results were as follows: (1) The transcription level of AhPRK4 was up-regulated after different aluminum treatments time and different aluminum concentrations, indicating that AhPRK4 was an aluminum inducible gene. (2) The AhPRK4 protein had 673 amino acids with transmembrane domain, signal peptide and phosphorylation active sites, belonging to the LRR-III protein kinase family. (3) The GST-AhPRK4-CD recombinant protein was induced in vitro and verified by Western Blot. And the recombinant protein had phosphorylated on both serine/threonine and tyrosine residues, but had no significant auto-phosphorylation activity. In conclusion, AhPRK4 is an aluminum responsive gene, which participates in the regulation of short-term aluminum stress and is phosphorylated in vitro.

Peanut Arachis hypogaea is a segmental allotetraploid in the section Arachis of the genus Arachis along with the Section Rhizomataceae. Section Arachis has several diploid species along with Arachis hypogaea and A. monticola. The section Rhizomataceae comprises polyploid species. Several species in the genus are highly tolerant to biotic and abiotic stresses and provide excellent sets of genotypes for studies on differential gene expression. Though there were several studies in this direction, more studies are needed to identify more and more gene combinations. Next generation RNA-seq based differential gene expression study is a powerful tool to identify the genes and regulatory pathways involved in stress tolerance. Transcriptomic and proteomic study of peanut plants under biotic stresses reveals a number of differentially expressed genes such as R genes (NBSLRR, LRR-RLK, protein kinases, MAP kinases), pathogenesis related proteins (PR1, PR2, PR5, PR10) and defense related genes (defensin, F-box, glutathione Stransferase) that are the most consistently expressed genes throughout the studies reported so far. In most of the studies on biotic stress induction, the differentially expressed genes involved in the process with enriched pathways showed plant-pathogen interactions, phenylpropanoid biosynthesis, defense and signal transduction. Differential gene expression studies in response to abiotic stresses, reported the most commonly expressed genes are transcription factors (MYB, WRKY, NAC, bZIP, bHLH, AP2/ERF), LEA proteins, chitinase, aquaporins, Fbox, cytochrome p450 and ROS scavenging enzymes. These differentially expressed genes are in enriched pathways of transcription regulation, starch and sucrosemetabolism, signal transduction and biosynthesis of unsaturated fatty acids. These identified differentially expressed genes provide a better understanding of the resistance/tolerancemechanism, and the genes for manipulating biotic and abiotic stress tolerance in peanut and other crop plants. There are a number of differentially expressed genes during biotic and abiotic stresses were successfully characterized in peanut or model plants (tobacco or Arabidopsis) by genetic manipulation to develop stress tolerance plants, which have been detailed out in this review and more concerted studies are needed to identify more and more gene/ gene combinations. [ABSTRACT FROM AUTHOR]

Peanut Arachis hypogaea is a segmental allotetraploid in the section Arachis of the genus Arachis along with the Section Rhizomataceae. Section Arachis has several diploid species along with Arachis hypogaea and A. monticola. The section Rhizomataceae comprises polyploid species. Several species in the genus are highly tolerant to biotic and abiotic stresses and provide excellent sets of genotypes for studies on differential gene expression. Though there were several studies in this direction, more studies are needed to identify more and more gene combinations. Next generation RNA-seq based differential gene expression study is a powerful tool to identify the genes and regulatory pathways involved in stress tolerance. Transcriptomic and proteomic study of peanut plants under biotic stresses reveals a number of differentially expressed genes such as R genes (NBS-LRR, LRR-RLK, protein kinases, MAP kinases), pathogenesis related proteins (PR1, PR2, PR5, PR10) and defense related genes (defensin, F-box, glutathione S-transferase) that are the most consistently expressed genes throughout the studies reported so far. In most of the studies on biotic stress induction, the differentially expressed genes involved in the process with enriched pathways showed plant-pathogen interactions, phenylpropanoid biosynthesis, defense and signal transduction. Differential gene expression studies in response to abiotic stresses, reported the most commonly expressed genes are transcription factors (MYB, WRKY, NAC, bZIP, bHLH, AP2/ERF), LEA proteins, chitinase, aquaporins, F-box, cytochrome p450 and ROS scavenging enzymes. These differentially expressed genes are in enriched pathways of transcription regulation, starch and sucrose metabolism, signal transduction and biosynthesis of unsaturated fatty acids. These identified differentially expressed genes provide a better understanding of the resistance/tolerance mechanism, and the genes for manipulating biotic and abiotic stress tolerance in peanut and other crop plants. There are a number of differentially expressed genes during biotic and abiotic stresses were successfully characterized in peanut or model plants (tobacco or Arabidopsis) by genetic manipulation to develop stress tolerance plants, which have been detailed out in this review and more concerted studies are needed to identify more and more gene/gene combinations.

Summary: Legumes can host nitrogen‐fixing rhizobia inside root nodules. In model legumes, rhizobia enter via infection threads (ITs) and develop nodules in which the infection zone contains a mixture of infected and uninfected cells. Peanut (Arachis hypogaea) diversified from model legumes c. 50–55 million years ago. Rhizobia enter through 'cracks' to form nodules in peanut roots where cells of the infection zone are uniformly infected. Phylogenomic studies have indicated symbiosis as a labile trait in peanut. These atypical features prompted us to investigate the molecular mechanism of peanut nodule development.Combining cell biology, genetics and genomic tools, we visualized the status of hormonal signaling in peanut nodule primordia. Moreover, we dissected the signaling modules of Nodule INception (NIN), a master regulator of both epidermal infection and cortical organogenesis.Cytokinin signaling operates in a broad zone, from the epidermis to the pericycle inside nodule primordia, while auxin signaling is narrower and focused. Nodule INception is involved in nodule organogenesis, but not in crack entry. Nodulation Pectate Lyase, which remodels cell walls during IT formation, is not required. By contrast, Nodule enhanced Glycosyl Hydrolases (AhNGHs) are recruited for cell wall modification during crack entry.While hormonal regulation is conserved, the function of the NIN signaling modules is diversified in peanut. [ABSTRACT FROM AUTHOR]

Summary: The simultaneous symbiosis of leguminous plants with two root mutualists, endophytic fungi and rhizobia is common in nature, yet how two mutualists interact and co‐exist before infecting plants and the concomitant effects on nodulation are less understood.Using a combination of metabolic analysis, fungal deletion mutants and comparative transcriptomics, we demonstrated that Bradyrhizobium and a facultatively biotrophic fungus, Phomopsis liquidambaris, interacted to stimulate fungal flavonoid production, and thereby primed Bradyrhizobial nodulation signaling, enhancing Bradyrhizobial responses to root exudates and leading to early nodulation of peanut (Arachis hypogaea), and such effects were compromised when disturbing fungal flavonoid biosynthesis.Stress sensitivity assays and reactive oxygen species (ROS) determination revealed that flavonoid production acted as a strategy to alleviate hyphal oxidative stress during P. liquidambaris–Bradyrhizobial interactions. By investigating the interactions between P. liquidambaris and a collection of 38 rhizobacteria, from distinct bacterial genera, we additionally showed that the flavonoid‐ROS module contributed to the maintenance of fungal and bacterial co‐existence, and fungal niche colonization under soil conditions.Our results demonstrate for the first time that rhizobial nodulation signaling can be primed by fungi before symbiosis with host plants and highlight the importance of flavonoid in tripartite interactions between legumes, beneficial fungi and rhizobia. [ABSTRACT FROM AUTHOR]

The far-red-impaired response 1 (FAR1) transcription family were initially identified as important factors for phytochrome A (phyA)-mediated far-red light signaling in Arabidopsis ; they play crucial roles in controlling the growth and development of plants. The reported reference genome sequences of Arachis , including A. duranensis , A. ipaensis , A. monticola , and A. hypogaea , and its related species Glycine max provide an opportunity to systematically perform a genome-wide identification of FAR1 homologous genes and investigate expression patterns of these members in peanut species. Here, a total of 650 FAR1 genes were identified from four Aarchis and its closely related species G. max. Of the studied species, A. hypogaea contained the most (246) AhFAR1 genes, which can be classified into three subgroups based on phylogenic relationships. The synonymous (Ks) and non-synonymous (Ka) substitution rates, phylogenetic relationship and synteny analysis of the FAR1 family provided deep insight into polyploidization, evolution and domestication of peanut AhFAR1 genes. The transcriptome data showed that the AhFAR1 genes exhibited distinct tissue- and stage-specific expression patterns in peanut. Three candidate genes including Ahy_A10g049543 , Ahy_A06g026579 , and Ahy_A10g048401 , specifically expressed in peg and pod, might participate in pod development in the peanut. The quantitative real-time PCR (qRT-PCR) analyses confirmed that the three selected genes were highly and specifically expressed in the peg and pod. This study systematically analyzed gene structure, evolutionary characteristics and expression patterns of FAR1 gene family, which will provide a foundation for the study of genetic and biological function in the future. [ABSTRACT FROM AUTHOR]

The far-red-impaired response 1 (FAR1) transcription family were initially identified as important factors for phytochrome A (phyA)-mediated far-red light signaling in Arabidopsis; they play crucial roles in controlling the growth and development of plants. The reported reference genome sequences of Arachis, including A. duranensis, A. ipaensis, A. monticola, and A. hypogaea, and its related species Glycine max provide an opportunity to systematically perform a genome-wide identification of FAR1 homologous genes and investigate expression patterns of these members in peanut species. Here, a total of 650 FAR1 genes were identified from four Aarchis and its closely related species G. max. Of the studied species, A. hypogaea contained the most (246) AhFAR1 genes, which can be classified into three subgroups based on phylogenic relationships. The synonymous (Ks) and non-synonymous (Ka) substitution rates, phylogenetic relationship and synteny analysis of the FAR1 family provided deep insight into polyploidization, evolution and domestication of peanut AhFAR1 genes. The transcriptome data showed that the AhFAR1 genes exhibited distinct tissue- and stage-specific expression patterns in peanut. Three candidate genes including Ahy_A10g049543, Ahy_A06g026579, and Ahy_A10g048401, specifically expressed in peg and pod, might participate in pod development in the peanut. The quantitative real-time PCR (qRT-PCR) analyses confirmed that the three selected genes were highly and specifically expressed in the peg and pod. This study systematically analyzed gene structure, evolutionary characteristics and expression patterns of FAR1 gene family, which will provide a foundation for the study of genetic and biological function in the future.

A series of landmark studies have provided conclusive evidence that the early administration of food allergens dramatically prevents the emergence of food allergy. One of the greatest remaining challenges is whether patients with established food allergy can return to health. This challenge is particularly pressing in the case of allergies against peanut, tree nuts, fish, and shellfish which are lifelong in most patients and may elicit severe reactions. The standard of care for food allergy is allergen avoidance and the timely administration of epinephrine upon accidental exposure. Epinephrine, and other therapeutic options like antihistamines provide acute symptom relief but do not target the underlying pathology of the disease. In principle, any transformative treatment for established food allergy would require the restoration of a homeostatic immunological state. This may be attained through either an active, non-harmful immune response (immunological tolerance) or a lack of a harmful immune response (e.g., anergy), such that subsequent exposures to the allergen do not elicit a clinical reaction. Importantly, such a state must persist beyond the course of the treatment and exert its protective effects permanently. In this review, we will discuss the immunological mechanisms that maintain lifelong food allergies and are, consequently, those which must be dismantled or reprogrammed to instate a clinically non-reactive state. Arguably, the restoration of such a state in the context of an established food allergy would require a reprogramming of the immune response against a given food allergen. We will discuss existing and experimental therapeutic strategies to eliminate IgE reactivity and, lastly, will propose outstanding questions to pave the road to the development of novel, transformative therapeutics in food allergy.

Aims: A cadmium (Cd)‐tolerant Bacillus megaterium strain A14 was used to investigate the effects and mechanisms of bacterial inoculation on peanut growth, Cd accumulation in grains and Cd fixation in Cd‐contaminated soil. Methods and Results: Spectroscopic analysis showed that A14 has many functional groups (‐OH, ‐NH2 and ‐COO et al.) distributed on its surface. The pot experiment indicated that compared to the Cd‐contaminated soil alone treatment, inoculation with strain A14 increased shoot and root biomass by 59·93 and 58·31% respectively. The accumulation of Cd in grains decreased by 48·14%, while the proportion of exchangeable Cd in soil decreased from 40 to 26% in A14 inoculated soil. Conclusions: Inoculation with B. megaterium A14 improved peanut plant growth via (i) adsorbing Cd2+ through functional groups on cell surface, (ii) immobilization of Cd in soil through extracellular secretions, (iii) scavenging the reactive oxygen species through production of antioxidant enzymes, and (iv) by reducing the phytoavailable Cd through regulation of Cd transport gene expression. Significance and Impact of the Study: This study provided a new sight on microbial approach for the chemical composition transformation of soil Cd and associated food safety production, which pointed out an efficient way to improve peanut cultivation. [ABSTRACT FROM AUTHOR]

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The peanut, also known as the groundnut, goober (US), pindar (US) or monkey nut (UK), and taxonomically classified as Arachis hypogaea, is a legume crop grown mainly for its edible seeds. It is widely grown in the tropics and subtropics, being important to both small and large commercial producers. It is classified as both a grain legume and, due to its high oil content, an oil crop. In this article, the analysis of the field experiments conducted in the Tashkent province, which was aimed at improving the technology of high-quality production was given. In the field experiments, the effect of Microzym-2 biostimulator on growth, development, yield elements, yield and seed quality of local peanut varieties "Salomat" (control) and "Mumtoz" was studied. [ABSTRACT FROM AUTHOR]

Endophytes are considered to be excellent biocontrol agents and biofertilizers, and are associated with plant growth promotion and health. In particular, seed-endophytic bacteria benefit the host plant’s progeny via vertical transmission, and can play a role in plant growth and defense. However, seed-associated endophytic bacteria have not been fully explored, with very little known about how they interact with peanut (Arachis hypogaea), for example. Here, 10 genera of endophytic bacteria were isolated from the root tips of peanut seedlings grown either aseptically or in soil. Forty-two bacterial colonies were obtained from peanut seedlings grown in soil, mostly from the genus Bacillus. Eight colonies were obtained from aseptic seedling root tips, including Bacillus sp., Paenibacillus sp., and Pantoea dispersa. Four Bacillus peanut strains GL1–GL4 (B.p.GL1-GL4) produced bio-films, while B.p.GL2 and Paenibacillus glycanilyticus YMR3 (P.g.YMR3) showed strong amylolytic capability, enhanced peanut biomass, and increased numbers of root nodules. Conversely, P. dispersa YMR1 (P.d.YMR1) caused peanut plants to wilt. P.g.YMR3 was distributed mainly around or inside vacuoles and was transmitted to the next generation through gynophores and ovules. Hexanoate, succinate, and jasmonic acid (JA) accumulated in peanut root tips after incubation with P.g.YMR3, but linolenate content decreased dramatically. This suggests that strain P.g.YMR3 increases JA content (14.93-fold change) and modulates the metabolism of peanut to facilitate nodule formation and growth. These findings provide new insight into plant–seed endophytic bacterial interactions in peanut.

Although citrate transporters are involved in iron (Fe) translocation and aluminum (Al) tolerance in plants, to date none of them have been shown to confer both biological functions in plant species that utilize Fe-absorption Strategy I. In this study, we demonstrated that AhFRDL1, a citrate transporter gene from peanut (Arachis hypogaea) that is induced by both Fe-deficiency and Al-stress, participates in both root-to-shoot Fe translocation and Al tolerance. Expression of AhFRDL1 induced by Fe deficiency was located in the root stele, but under Al-stress expression was observed across the entire root-tip cross-section. Overexpression of AhFRDL1 restored efficient Fe translocation in Atfrd3 mutants and Al resistance in AtMATE -knockout mutants. Knocking down AhFRDL1 in the roots resulted in reduced xylem citrate and reduced concentrations of active Fe in young leaves. Furthermore, AhFRDL1 -knockdown lines had reduced root citrate exudation and were more sensitive to Al toxicity. Compared to an Al-sensitive variety, enhanced AhFRDL1 expression in an Fe-efficient variety contributed to higher levels of Al tolerance and Fe translocation by promoting citrate secretion. These results indicate that AhFRDL1 plays a significant role in Fe translocation and Al tolerance in Fe-efficient peanut varieties under different soil-stress conditions. Given its dual biological functions, AhFRDL1 may serve as a useful genetic marker for breeding for high Fe efficiency and Al tolerance. [ABSTRACT FROM AUTHOR]

Abstract: Spotted wilt, caused by tomato spotted wilt virus (TSWV), is a major disease of peanut (Arachis hypogaea) in the south‐eastern United States. Cultivar resistance is the most important factor in disease control. However, spotted wilt resistance in current cultivars still carries risk in the absence of other practices when disease is severe. In contrast, a newly developed cultivar, Florida‐EP™ “113,” has demonstrated excellent resistance even when spotted wilt is severe. Information on heritability of this resistance can help breeders better utilize it in breeding. F2‐derived populations from the cross Florida‐EP™ “113”/Georgia Valencia were developed and tested in field experiments in Florida from 2012 to 2014. Disease symptoms were evaluated visually, and the frequency of TSWV infection was measured by ImmunoStrip®. Heritability estimated from ImmunoStrip® was higher (0.66) compared to visual ratings (0.48). Genetic correlations among evaluation methods (rA = 0.92–0.99) and environments (rB = 0.86–0.99) were high. These results indicate that resistance in Florida‐EP™ “113” is highly heritable and that selection in a high disease risk environment is feasible without significant erosion of genetic gain. [ABSTRACT FROM AUTHOR]

Seed-coat cracking and undesirable color of seed coat highly affects external appearance and commercial value of peanuts (Arachis hypogaea L.). With an objective to find genetic solution to the above problems, a peanut mutant with cracking and brown colored seed coat (testa) was identified from an EMS treated mutant population and designated as peanut seed coat crack and brown color mutant line (pscb). The seed coat weight of the mutant was almost twice of the wild type, and the germination time was significantly lower than wild type. Further, the mutant had lower level of lignin, anthocyanin, proanthocyandin content and highly increased level of melanin content as compared to wild type. Using RNA-Seq, we examined the seed coat transcriptome in three stages of seed development in the wild type and the pscb mutant. The RNA-Seq analysis revealed presence of highly differentially expressed phenylpropanoid and flavonoid pathway genes in all the three seed development stages, especially at 40 days after flowering (DAF40). Also, the expression of polyphenol oxidases and peroxidase were found to be activated significantly especially in the late seed developmental stage. The genome-wide comparative study of the expression profiles revealed 62 differentially expressed genes common across all the three stages. By analyzing the expression patterns and the sequences of the common differentially expressed genes of the three stages, three candidate genes namely c36498_g1 (CCoAOMT1), c40902_g2 (kinesin) and c33560_g1 (MYB3) were identified responsible for seed-coat cracking and brown color phenotype. Therefore, this study not only provided candidate genes but also provided greater insights and molecular genetic control of peanut seed-coat cracking and color variation. The information generated in this study will facilitate further identification of causal gene and diagnostic markers for breeding improved peanut varieties with smooth and desirable seed coat color.

Peanut contains protein, oil, oleic acid, and linoleic acid its flavor is largely determined by pyrazine and aldehyde compounds. Both nutritional value and flavor are standards for measuring peanut quality. In this report, the contents of protein, oil, oleic acid, and linoleic acid were determined using near-infrared reflectance spectroscopy, and flavor compounds were identified using headspace solid-phase microextraction combined with gas chromatography–mass spectrometry in 12 different peanut cultivars. Our results showed that the content of oleic acid in raw peanut ranged from 35.69 to 82.79 g/100 g oil and the linoleic acid content ranged from 2.92 to 44.19 g/100 g oil, with high coefficients of variation. The coefficients of variation of protein and oil were lower, with content of 26.97–33.07 g/100 g raw materials and 45.53–55.53 g/100 g raw materials, respectively. Overall, 14 volatile components were isolated and identified, among which pyrazine and aldehyde compounds were the major aroma components in 12 different peanut cultivars.. Based on these results, peanuts with high protein content have high linoleic oil levels but low oleic oil levels, and roasted peanuts have a high content of pyrazines but low content of aldehydes. The results of this study will enable manufacturers to develop simple tests that predict the flavor of roasted peanuts based on their composition. [ABSTRACT FROM AUTHOR]

BACKGROUND Epitope identification provides valuable information essential for understanding antigen components involved in food allergic reactions. In the present study, an in silico approach is employed to map IgE binding epitopes of major and minor peanut allergens. RESULTS B-cell epitopes were identified for peanut ( Arachis hypogaea) allergens, namely Ara h 5, 6, 7, 8, 9, 10 and 11. A total of 10 web servers were used in the study and 26 linear and 18 conformational epitopes were predicted by a combination of methods. The majority of the predicted B-cell residues were present in the coil regions and the highest percentage of hydrophilic residues were observed for Ara h 6 (70.49%). The absolute solvent accessibility for all the B-cell epitopes was >70%, indicating antibody recognition. The property distance index assessed for the predicted epitopes using SDAP showed that six linear epitopes shared similarity with soybean, hazelnut, tomato, maize, apple and banana allergens. CONCLUSION These findings suggest that the identified regions may share cross-reactivity with some of the known food allergens or may act as novel antigenic determinants. Further, B-cell epitopes of Ara h 1, 2 and 3 identified by in silico methods correlated well with the experimentally identified regions. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

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Highlights: [•] Regulated and non-regulated mycotoxins were determined in various types of nuts. [•] Multi-matrix and multi-toxin (UHPLC–MS/MS) method was tested. [•] Out of 10 mycotoxins analyzed only one was detected (ZEA). [•] All the samples complied with current European/Serbian legislation. [•] This is the first report about occurrence of studied mycotoxins in nuts from Serbia. [Copyright &y& Elsevier]

Taking two peanut varieties Huayu 17 and Tangke 8 as test objects, a soil column culture experiment was conducted in a rainproof tank to study the peanut root morphological development and physiological characteristics at late growth stages under moderate drought and well-watered conditions. Tanke 8 had more developed root system and higher yield and drought coefficient, while Huayu 17 had poorer root adaptability to drought stress. For the two varieties, their root length density and root biomass were mainly distributed in 0-40 cm soil layer, whereas their root traits differed in the same soil layer. The total root length, total root surface area, and total root volume of Huayu 17 at each growth stage were smaller under drought stress than under well-balanced water treatment, while these root characteristics of Tangke 8 under drought stress only decreased at flowering-pegging stage. Drought stress increased the root biomass, surface area, and volume of the two varieties in 20-40 cm soil layer, but decreased these root traits in the soil layers below 40 cm. Under drought stress, the root activity of the two varieties in the soil layers below 40 cm at pod filling stage decreased, and the decrement was larger for Huayu 17. The differences in the root system development and physiological characteristics of the two varieties at late growth stages under drought stress suggested that the root system of the two varieties had different water absorption and utilization under drought stress. [ABSTRACT FROM AUTHOR]

Abstract: Peanut allergic reactions can result from the ingestion of even very small quantities of peanut and represent a severe threat to the health of sensitized individuals. In order to protect the allergic consumer, efficient and reliable methods are required for the detection of allergenic ingredients. For this purpose, we have developed a TaqMan real-time PCR method for specific detection of peanut in commercial food products. The assay uses two genetic makers in the Arah2 (125 bp) and ITS1 (90 bp) gene respectively, and TaqMan probes. The nuclear 18S rRNA gene was employed as a positive amplification control. Results obtained on sensitivity of both Arah2 and ITS primers with mixtures spiked with different concentrations of the target showed detection levels of 10 and 0.1 ppm, respectively. The applicability of the real-time PCR protocol to detect the presence of peanut DNA in commercial food products was determined through analysis of 123 different commercial products with the ITS primers which aimed higher sensitivity than Arah2 primer pair. The performance of the real-time PCR proposed herein allows a highly sensitive detection of peanut DNA in all the different food products, which declared to contain peanut material as well as in others were the presence of peanut or its traces wasn''t declared in the labeling. [Copyright &y& Elsevier]

Background: Cultivated peanut or groundnut (Arachis hypogaea L.) is an important oilseed crop with an allotetraploid genome (AABB, 2n = 4x = 40). Both the low level of genetic variation within the cultivated gene pool and its polyploid nature limit the utilization of molecular markers to explore genome structure and facilitate genetic improvement. Nevertheless, a wealth of genetic diversity exists in diploid Arachis species (2n = 2x = 20), which represent a valuable gene pool for cultivated peanut improvement. Interspecific populations have been used widely for genetic mapping in diploid species of Arachis. However, an intraspecific mapping strategy was essential to detect chromosomal rearrangements among species that could be obscured by mapping in interspecific populations. To develop intraspecific reference linkage maps and gain insights into karyotypic evolution within the genus, we comparatively mapped the A- and B-genome diploid species using intraspecific F2 populations. Exploring genome organization among diploid peanut species by comparative mapping will enhance our understanding of the cultivated tetraploid peanut genome. Moreover, new sources of molecular markers that are highly transferable between species and developed from expressed genes will be required to construct saturated genetic maps for peanut. Results: A total of 2,138 EST-SSR (expressed sequence tag-simple sequence repeat) markers were developed by mining a tetraploid peanut EST assembly including 101,132 unigenes (37,916 contigs and 63,216 singletons) derived from 70,771 long-read (Sanger) and 270,957 short-read (454) sequences. A set of 97 SSR markers were also developed by mining 9,517 genomic survey sequences of Arachis. An SSR-based intraspecific linkage map was constructed using an F2 population derived from a cross between K 9484 (PI 298639) and GKBSPSc 30081 (PI 468327) in the B-genome species A. batizocoi. A high degree of macrosynteny was observed when comparing the homoeologous linkage groups between A (A. duranensis) and B (A. batizocoi) genomes. Comparison of the A- and B-genome genetic linkage maps also showed a total of five inversions and one major reciprocal translocation between two pairs of chromosomes under our current mapping resolution. Conclusions: Our findings will contribute to understanding tetraploid peanut genome origin and evolution and eventually promote its genetic improvement. The newly developed EST-SSR markers will enrich current molecular marker resources in peanut. [ABSTRACT FROM AUTHOR]

Lateral flow devices (LFDs) are qualitative immunochromatographic tests for the rapid and specific detection of target analytes. We investigated commercially available LFDs for their ability to detect potentially allergenic peanut and hazelnut in raw cookie dough and chocolate, two important food matrices in the industrial production of cookies. Each three commercial LFDs for the detection of hazelnut and peanut were performed according to the manufacturers’ instructions. All LFDs had comparably satisfactory specificity that was investigated with a variety of characteristic foods and food ingredients used in the production of cookies. In concordance with hazelnut-specific enzyme-linked immunosorbent assays (ELISAs), walnut was the most cross-reactive food for hazelnut-specific LFD. The sensitivity was verified in raw cookie doughs and chocolates that were either spiked with peanut or hazelnut between 1 and 25 mg/kg, respectively. Two hazelnut-specific LFDs detected hazelnut at a level of 3.5 mg/kg in both matrices, whereas the third LFD detected hazelnut at a level of 3.9 mg/kg in dough and 12.5 mg/kg in chocolate. Two peanut-specific LFDs detected peanut at a level of 1 mg/kg in both matrices. The third LFD detected peanut at a level of 14.2 mg/kg in chocolate and 4 mg/kg in dough. In conclusion, specific and sensitive LFD were identified for each hazelnut and peanut, having a level of sensitivity that is comparable to commercial ELISA for the investigated matrices. Such sensitive, specific, and rapid tests are useful analytical tools for allergen screening and sanitation in the industrial manufacture of foods. [ABSTRACT FROM AUTHOR]

Abstract: After pre-culture and treatment of osmosis, zygotic embryos of peanut (Arachis hypogaea L.) were transformed via particle bombardment with a plasmid containing a Bluetongue VP2 gene (BTVP2) comprising neutralizing epitopes. Selection for Kanamycin resistant calluses and somatic embryos was initiated at 12th day post-bombardment on medium containing 25mg/L Kanamycin. Under continuous selection, 12.38% Kanamycin resistant plantlets were regenerated from bombarded somatic embryos. The presence and integration of BTVP2 DNA in regenerated Kanamycin resistant plants were confirmed by southern hybridization assay using non-radioactive Digoxiginin BTVP2 probe. β-Glucuronidase (GUS) enzyme activity was detected in transgenic somatic embryos but not from control, non-transformed embryos. The expression of the BTVP2 protein was confirmed through RT-PCR (reverse transcription polymerase chain reaction) using the RNA isolated from the transgenic callus employing BTVP2-specific primers. The production of transgenic peanut was mainly focused on evaluating a newly improved somatic embryogenesis regeneration system as well as the gene transfer method and to produce the Bluetongue outer coat protein that comprises the neutralizing epitopes. [Copyright &y& Elsevier]

A high degree of genetic diversity among 125 peanut bradyrhizobial strains and among 32 peanut cultivars collected from different regions of China was revealed by using the amplified fragment length polymorphism (AFLP) technique. Eighteen different peanut bradyrhizobial genotypes and six peanut cultivars were selected for symbiotic cross-inoculation experiments. The genomic diversity was reflected in the symbiotic diversity. The peanut cultivars varied in their ability to nodulate with the strains used. Some cultivars had a more restricted host range than the others. Also the strains displayed a range of nodulation patterns. In yield formation there were clear differences between the plant cultivar/bradyrhizobium combinations. There was good compatibility between some peanut bradyrhizobial strains and selected cultivars, with inoculation resulting in well-nodulated, high-yielding symbiotic combinations, but no plant cultivar was compatible with all strains used. The strains displayed a varying degree of effectiveness, with some strains being fairly effective with all cultivars and others with selected ones. The AFLP genotypes of the strains did not explain the symbiotic behavior, whereas the yield formation of the plant cultivars was more related to the genotype. It is concluded that to obtain optimal nitrogen fixation efficiency of peanut in the field, compatible plant cultivar-bradyrhizobium combinations should be selected either by finding inoculant strains compatible with the plant cultivars used, or plant cultivars compatible with the indigenous bradyrhizobia. [ABSTRACT FROM AUTHOR]

Abstract Background Peanut (Arachis hypogaea) is an autogamous allotetraploid legume (2n = 4x = 40) that is widely cultivated as a food and oil crop. More than 6,000 DNA markers have been developed in Arachis spp., but high-density linkage maps useful for genetics, genomics, and breeding have not been constructed due to extremely low genetic diversity. Polymorphic marker loci are useful for the construction of such high-density linkage maps. The present study used in silico analysis to develop simple sequence repeat-based and transposon-based markers. Results The use of in silico analysis increased the efficiency of polymorphic marker development by more than 3-fold. In total, 926 (34.2%) of 2,702 markers showed polymorphisms between parental lines of the mapping population. Linkage analysis of the 926 markers along with 253 polymorphic markers selected from 4,449 published markers generated 21 linkage groups covering 2,166.4 cM with 1,114 loci. Based on the map thus produced, 23 quantitative trait loci (QTLs) for 15 agronomical traits were detected. Another linkage map with 326 loci was also constructed and revealed a relationship between the genotypes of the FAD2 genes and the ratio of oleic/linoleic acid in peanut seed. Conclusions In silico analysis of polymorphisms increased the efficiency of polymorphic marker development, and contributed to the construction of high-density linkage maps in cultivated peanut. The resultant maps were applicable to QTL analysis. Marker subsets and linkage maps developed in this study should be useful for genetics, genomics, and breeding in Arachis. The data are available at the Kazusa DNA Marker Database (http://marker.kazusa.or.jp).

Peanut ( Arachis hypogaea ) Allergen Powder-dnfp (Palforzia, Aimmune™ Therapeutics, Inc.; Brisbane, CA) is the first FDA-approved oral immunotherapy indicated for the mitigation of allergic reactions, including anaphylaxis, in patients with peanut allergy. It may be initiated in individuals 4 to 17 years of age and continued for maintenance in those 4 years of age and older. Initiation and dose titration require a stepwise approach and the supervision of a health care professional. Patients taking Peanut ( Arachis hypogaea ) Allergen Powder-dnfp should also follow a peanut-avoidant diet. In addition, patients should have an injectable epinephrine product in case of drug-related anaphylaxis. Commonly reported adverse reactions include gastrointestinal, respiratory, and dermatologic manifestations that are frequently associated with allergic reactions., Competing Interests: Disclosures. The authors declare no conflicts or financial interest in any product or service mentioned in the manuscript, including grants, equipment, medications, employment, gifts, and honoraria., (Copyright. Pediatric Pharmacy Association. All rights reserved. For permissions, email: mhelms@pediatricpharmacy.org 2021.)

Ara h 2 was purified from peanuts that were thermally treated by various processes, including boiling, glycation, frying and roasting. The allergenicity of Ara h 2 in Balb/c mice and the influence of thermal processing on the structural characteristics, and binding capacity of three core antigenic epitopes were studied. The results demonstrated that boiling, glycation and frying induced the down-regulation of the allergenicity of Ara h 2 in Balb/c mice, the collapse of its tertiary/secondary structure, and a reduction in the core epitope binding capacity; roasting showed a comparable allergenicity and the weakest inhibitory effect on core epitope binding capacity. These results indicate that thermal processing causes alteration of the protein structure and core epitopes of Ara h 2, and may affect its allergenicity., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The rAra h 2.02 was studied to determine the influence of heat treatment on its structure and core IgE-binding epitopes. The results of SDS-PAGE, Western blotting, MALDI-TOF-MS, and atomic force microscopy showed that the structure of rAra h 2.02 was altered after boiling (100°C) or autoclaving (121°C) for 20min. Furthermore, some of the protein may be aggregated. Results of circular dichroism spectroscopy showed that the α-helices content was reduced, while β-turns and random coils were increased by 81% and 27%, respectively, after autoclaving. Antibodies of three core IgE-binding epitopes were used to determine the binding capacity of rAra h 2.02 after thermal processing by indirect ELISA. The results showed that the binding capacities of the three core IgE-binding epitopes were changed after different heat treatments., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Specific primer sets were designed based on the DNA sequence of Ara h 1, one of the major peanut (Arachis hypogaea) allergens, and a competitive internal amplification control (IAC) was designed by compound primer technology. By choosing 314 copies/PCR as the IAC dosage, a Real-time PCR method with IAC was established for detecting peanut allergen Ara h 1 DNA. The method showed high specificity with a detection limit of 0.005% peanut. A series of commercial food products with/without peanut components were tested. Among these products, the peanut allergen Ara h 1 DNA could be detected in 12 products labelled containing peanut ingredients, in two without a declaration of peanut and one labelled that was produced in a facility that produced peanut-containing foods. This indicates that the method is highly sensitive for the detection of peanut ingredients in foods., (Copyright © 2014 Elsevier Ltd. All rights reserved.)