Peanut Tolerance Research Articles

Tolerance of peanuts and tree nuts in Spanish children with exclusive sensitization to lipid transfer proteins.

Allergy to peanuts and tree nuts is a common cause of food allergy in Spain, with lipid transfer proteins (LTP) being the most frequently recognized panallergen. LTP sensitization often leads to multiple food group sensitivities, resulting in overly restrictive diets that hinder patient's quality of life. This study aimed to assess the tolerance of peanuts and tree nuts (hazelnuts and walnuts) in children sensitized to LTP, potentially mitigating the need for such diets. This prospective study enrolled individuals diagnosed with allergy to peanuts, hazelnuts, or walnuts. Data were collected from medical records, including demographics and clinical history. Allergological assessment comprised skin prick tests using commercial extracts and the nuts in question, alongside measurements of total and specific IgE to nuts and their primary molecular components. Participants showing positive LTP sensitization without sensitization to seed storage proteins underwent open oral nut challenges. A total of 75 individuals labeled as allergic to peanuts, 44 to hazelnuts, and 51 to walnuts were included. All of them underwent an open oral provocation test with the incriminated nut, showing a high tolerance rate. Peanut was tolerated by 98.6% of patients, 97.72% tolerated hazelnut, and 84.3% tolerated walnut. The findings suggest that the majority of patients allergic to peanuts, hazelnuts, or walnuts, due to LTP sensitization and lacking IgE reactivity to seed storage proteins, can tolerate these nuts. This supports the need for personalized nut tolerance assessments to avoid unnecessary dietary restrictions.

Polyvinyl chloride and polybutylene adipate microplastics affect peanut and rhizobium symbiosis by interfering with multiple metabolic pathways

Microplastics (MPs), widely presented in cultivated soil, have caused serious stresses on crop growth. However, the mechanism by which MPs affect legumes and rhizobia symbiosis is still unclear. Here, peanut seedlings were inoculated with Bradyrhizobium zhanjiangense CCBAU 51778 and were grown in vermiculite with 3 %/5 % (w/w) addition of PVC (polyvinyl chloride)-MPs/PBAT (polybutylene adipate)-MPs. PVC-MPs and PBAT-MPs separately decreased nodule number by 33–100 % and 2.62–80.91 %. Transcriptome analysis showed that PVC-MPs affected more DEGs (differentially expressed genes) than PBAT-MPs, indicating PVC-MPs were more devastating for the symbiosis than PBAT-MPs. Functional annotation revealed that PVC-MPs and PBAT-MPs enriched DEGs related to biosynthesis pathways such as flavonoid, isoflavonoid, and phenylpropanoid, in peanut. And when the dose increased from 3 % to 5 %, PVC-MPs mainly enriched the pathways of starch and sucrose metabolism, alanine, aspartate and glutamate metabolism, diterpenoid biosynthesis, etc.; PBAT-MPs enriched cysteine and methionine metabolism, photosynthesis, MAPK signaling, and other pathways. These significantly enriched pathways functioned in reducing nodule number and promoting peanut tolerance to MPs stresses. This study reveals the effect of PVC-MPs and PBAT-MPs on peanut and rhizobium symbiosis, and provides new perspectives for legume production and environmental safety.

Follow-up to Adolescence after Early Peanut Introduction for Allergy Prevention

BackgroundA randomized trial demonstrated consumption of peanut from infancy to age 5 years prevented the development of peanut allergy. An extension of that trial demonstrated the effect persisted after 1 year of peanut avoidance. This follow-up trial examined the durability of peanut tolerance at age 144 months after years of ad libitum peanut consumption.MethodsParticipants from a randomized peanut consumption trial were assessed for peanut allergy following an extended period of eating or avoiding peanuts as desired. The primary end point was the rate of peanut allergy at age 144 months.ResultsWe enrolled 508 of the original 640 participants (79.4%); 497 had complete primary end point data. At age 144 months, peanut allergy remained significantly more prevalent in participants in the original peanut avoidance group than in the original peanut consumption group (15.4% [38 of 246 participants] vs. 4.4% [11 of 251 participants]; P<0.001). Participants in both groups reported avoiding peanuts for prolonged periods of time between 72 and 144 months. Participants at 144 months in the peanut consumption group had levels of Ara h2-specific immunoglobulin E (a peanut allergen associated with anaphylaxis) of 0.03 ± 3.42 kU/l and levels of peanut-specific immunoglobulin G4 of 535.5 ± 4.98 μg/l, whereas participants in the peanut avoidance group had levels of Ara h2-specific immunoglobulin E of 0.06 ± 11.21 kU/l and levels of peanut-specific immunoglobulin G4 of 209.3 ± 3.84 μg/l. Adverse events were uncommon, and the majority were related to the food challenge.ConclusionsPeanut consumption, starting in infancy and continuing to age 5 years, provided lasting tolerance to peanut into adolescence irrespective of subsequent peanut consumption, demonstrating that long-term prevention and tolerance can be achieved in food allergy. (Funded by the National Institute of Allergy and Infectious Diseases and others; ITN070AD, ClinicalTrials.gov number, NCT03546413.)

Melatonin seed priming improves early establishment and water stress tolerance of peanut

Water stress is a major cause of yield loss in peanut cultivation. Melatonin seed priming has been used to enhance stress tolerance in several crops, but not in peanut. We investigated the impact of seed priming with melatonin on the growth, development, and drought tolerance of two peanut cultivars, TUFRunner™ ‘511’, a drought tolerant cultivar, and New Mexico Valencia A, a drought sensitive cultivar. Peanut seed priming tests using variable rates of melatonin (0–200 μM), indicated that 50 μM of melatonin resulted in more uniform seed germination and improved seedling growth in both cultivars under non stress conditions. Seed priming with melatonin also promoted vegetative growth, as evidenced by higher whole-plant transpiration, net CO2 assimilation, and root water uptake under both well-watered and water stress conditions in both cultivars. Higher antioxidant activity and protective osmolyte accumulation, lower reactive oxygen species accumulation and membrane damage were observed in primed compared with non-primed plants. Seed priming with melatonin induced a growth promoting effect that was more evident under well-watered conditions for TUFRunnner™ ‘511’, whereas for New Mexico Valencia A, major differences in physiological responses were observed under water stress conditions. New Mexico Valencia A primed plants exhibited a more sensitized stress response, with faster down-regulation of photosynthesis and transpiration compared with non-primed plants. The results demonstrate that melatonin seed priming has significant potential to improve early establishment and promote growth of peanut under optimal conditions, while also improve stress tolerance during water stress.

Physiological and biochemical mechanisms underlying the role of anthocyanin in acquired tolerance to salt stress in peanut (Arachis hypogaea L.).

Anthocyanin is an important pigment that prevents oxidative stress and mediates adaptation of plants to salt stress. Peanuts with dark red and black testa are rich in anthocyanin. However, correlation between salt tolerance and anthocyanin content in black and dark red testa peanuts is unknown. In this study, three peanut cultivars namely YZ9102 (pink testa), JHR1 (red testa) and JHB1 (black testa) were subjected to sodium chloride (NaCl) stress. The plant growth, ion uptake, anthocyanin accumulation, oxidation resistance and photosynthetic traits were comparatively analyzed. We observed that the plant height, leaf area and biomass under salt stress was highly inhibited in pink color testa (YZ9102) as compare to black color testa (JHB1). JHB1, a black testa colored peanut was identified as the most salt-tolerance cultivar, followed by red (JHR1) and pink(YZ9102). During salt stress, JHB1 exhibited significantly higher levels of anthocyanin and flavonoid accumulation compared to JHR1 and YZ9102, along with increased relative activities of antioxidant protection and photosynthetic efficiency. However, the K+/Na+ and Ca2+/Na+ were consistently decreased among three cultivars under salt stress, suggesting that the salt tolerance of black testa peanut may not be related to ion absorption. Therefore, we predicted that salt tolerance of JHB1 may be attributed to the accumulation of the anthocyanin and flavonoids, which activated antioxidant protection against the oxidative damage to maintain the higher photosynthetic efficiency and plant growth. These findings will be useful for improving salt tolerance of peanuts.

Potassium humate and cobalt enhance peanut tolerance to water stress through regulation of proline, antioxidants, and maintenance of nutrient homeostasis

Water stress is an important factor that substantially impacts crop production. As a result, there is a need for various strategies that can mitigate these negative effects. One such strategy is the application of potassium humate (Kh) and cobalt (Co), which have been reported to enhance the resistance of crop plants. Therefore, the present experiment was designed to investigate whether the application of Kh and Co could positively affect proline, chlorophyll and mineral elements contents, and antioxidant defense systems which in turn will mitigate the negative impact of water stress under different irrigation strategies. In 2021 and 2022, an open-field experiments were conducted by using a split-plot design. The main plots were divided to represent different irrigation strategies (ST), with additional control of full irrigation requirements (ST1). Four STs were implemented, with ST1, followed by the application of 75%, 50%, and 25% irrigation strategies in ST2, ST3, and ST4 respectively, in the next irrigation, followed by the full requirements, and so on. In the subplots, peanut plants were treated with tap water (Control), Kh at 2 g l−1 and 3 g l−1, Co, Co + Kh 2 g l−1 and Co + Kh 3 g l−1. The yield was negatively affected by the implementation of ST4, despite the increase in proline contents. Furthermore, there was a decrease in relative water content, chlorophyll content, antioxidant enzymes, protein, and mineral nutrient elements. However, the application of Kh or Co showed better improvements in most of the studied parameters. It is worth noting that there was an antagonistic relationship between Co and iron/manganese, and the intensity of this relationship was found to depend on the STs implemented. The highest mineral nutrient accumulation, chlorophyll content, relative water content, protein content, oil content, seed yield, and water productivity were observed when peanut plants were treated with Kh 3 g l−1 + Co under the ST2 water strategy.

A phase 2 study of Bruton's tyrosine kinase inhibition for the prevention of anaphylaxis.

IgE-mediated anaphylaxis is a potentially fatal systemic allergic reaction for which there are no currently FDA-approved preventative therapies. Bruton's tyrosine kinase (BTK) is an essential enzyme for IgE-mediated signaling pathways, and is an ideal pharmacologic target to prevent allergic reactions. In this open-label trial, we evaluated the safety and efficacy of acalabrutinib, a BTK inhibitor that is FDA-approved to treat some B cell malignancies, in preventing clinical reactivity to peanut in adults with peanut allergy. After undergoing graded oral peanut challenge to establish their baseline level of clinical reactivity, 10 patients had a 6-week rest period, then received four standard doses of 100 mg acalabrutinib twice daily and underwent repeat food challenge. The primary endpoint was the change in patients' threshold dose of peanut protein to elicit an objective clinical reaction. At baseline, patients tolerated a median of 29 mg of peanut protein before objective clinical reaction. During subsequent food challenge on acalabrutinib, patients' median tolerated dose significantly increased to 4,044 mg (range, 444 - 4,044 mg). Seven patients tolerated the maximum protocol amount (4,044 mg) of peanut protein with no clinical reaction, and the other 3 patients' peanut tolerance increased between 32- and 217-fold. Three patients experienced a total of 4 adverse events that were considered to be possibly related to acalabrutinib; all events were transient and nonserious. Acalabrutinib pretreatment achieved clinically-relevant increases in patients' tolerance to their food allergen, thereby supporting the need for larger, placebo-controlled trials. gov NCT05038904FUNDING. AstraZeneca Pharmaceuticals, the Johns Hopkins Institute for Clinical and Translational Research, the Ludwig Family Foundation, and NIH grants AI143965 and AI106043.

Advances in omics research on peanut response to biotic stresses.

Peanut growth, development, and eventual production are constrained by biotic and abiotic stresses resulting in serious economic losses. To understand the response and tolerance mechanism of peanut to biotic and abiotic stresses, high-throughput Omics approaches have been applied in peanut research. Integrated Omics approaches are essential for elucidating the temporal and spatial changes that occur in peanut facing different stresses. The integration of functional genomics with other Omics highlights the relationships between peanut genomes and phenotypes under specific stress conditions. In this review, we focus on research on peanut biotic stresses. Here we review the primary types of biotic stresses that threaten sustainable peanut production, the multi-Omics technologies for peanut research and breeding, and the recent advances in various peanut Omics under biotic stresses, including genomics, transcriptomics, proteomics, metabolomics, miRNAomics, epigenomics and phenomics, for identification of biotic stress-related genes, proteins, metabolites and their networks as well as the development of potential traits. We also discuss the challenges, opportunities, and future directions for peanut Omics under biotic stresses, aiming sustainable food production. The Omics knowledge is instrumental for improving peanut tolerance to cope with various biotic stresses and for meeting the food demands of the exponentially growing global population.

A MYB-related transcription factor from peanut, AhMYB30, improves freezing and salt stress tolerance in transgenic Arabidopsis through both DREB/CBF and ABA-signaling pathways.

Abiotic stresses such as salinity and low temperature have serious impact on peanut growth and yield. The present work investigated the function of a MYB-related transcription factor gene AhMYB30 obtained from peanut under salt and low temperature stresses by transgenic methods. The results indicated that the overexpression of AhMYB30 in Arabidopsis could enhance the resistance of transgenic plants to freezing and salt stresses. The expression of stress-response genes RD29A (Response-to-Dehydration 29A), COR15A (Cold-Regulated 15A), KIN1 (Kinesin 1) and ABI2 (Abscisic acid Insensitive 2) increased in transgenic plants compared with in wild-type. Subcellular localization and transcriptional autoactivation validation demonstrated that AhMYB30 has essential features of transcription factors. Therefore, AhMYB30 may increase salt and freezing stress tolerance as the transcription factor (TF) in Arabidopsis through both DREB/CBF and ABA-signaling pathways. Our results lay the theoretical foundation for exploring stress resistance mechanisms of peanut and offering novel genetic resources for molecular breeding.

Effect of ACC oxidase gene AhACOs on salt tolerance of peanut

ACC oxidase (ACO) is one of the key enzymes that catalyze the synthesis of ethylene. Ethylene is involved in salt stress response in plants, and salt stress seriously affects the yield of peanut. In this study, AhACO genes were cloned and their functions were investigated with the aim to explore the biological function of AhACOs in salt stress response, and to provide genetic resources for the breeding of salt-tolerant varieties of peanut. AhACO1 and AhACO2 were amplified from the cDNA of salt-tolerant peanut mutant M29, respectively, and cloned into the plant expression vector pCAMBIA super1300. The recombinant plasmid was transformed into Huayu22 by pollen tube injection mediated by Agrobacterium tumefaciens. After harvest, the small slice cotyledon was separated from the kernel, and the positive seeds were screened by PCR. The expression of AhACO genes was analyzed by qRT-PCR, and the ethylene release was detected by capillary column gas chromatography. Transgenic seeds were sowed and then irrigated with NaCl solution, and the phenotypic changes of 21-day-seedings were recorded. The results showed that the growth of transgenic plants were better than that of the control group Huayu 22 upon salt stress, and the relative content of chlorophyll SPAD value and net photosynthetic rate (Pn) of transgenic peanuts were higher than those of the control group. In addition, the ethylene production of AhACO1 and AhACO2 transgenic plants were 2.79 and 1.87 times higher than that of control peanut, respectively. These results showed that AhACO1 and AhACO2 could significantly improve the salt stress tolerance of transgenic peanut.

Soil metagenome and metabolome of peanut intercropped with sorghum reveal a prominent role of carbohydrate metabolism in salt-stress response

To understand the underlying mechanisms of the salt-stress response in peanuts intercropped with sorghum, soil metabolomics and metagenome sequencing were used to examine the metabolic profile and microbial composition of solo-cropped peanut (SP) and intercropped peanut (IP) under normal (N) and salt-stressed (S) soil conditions. In this investigation, 124 potential compounds were identified and categorized into 11 classes, with carbohydrates constituting the majority. Pathway enrichment analysis revealed that the most differentially expressed metabolic pathway was “carbohydrate metabolism,” and the main metabolites (e.g., D-Allose 2, Sucrose, Sorbitol 1, and Fructose 1) were more abundant in S-IP than in S-SP. Furthermore, the metagenomic analysis revealed that the relative abundances of Actinobacteria, Nitrospira, Massilia, and additional microbial taxa were significantly higher in S-IP than in S-SP. In addition, microbes exhibited a significant positive association with Sucrose and Sorbitol 1, and numerous microbial functions were involved in regulating carbohydrate metabolism in response to salt stress. Therefore, peanuts intercropped with sorghum under salt stress indirectly influenced the recruitment of beneficial microbial communities by altering the composition and content of metabolites, potentially increasing peanut's tolerance. These findings may provide a foundation for elucidating intercropping to improve the salt tolerance of peanuts as well as elucidate important information on the crucial metabolites and microbes that regulate the salt-stress response.

The Likelihood of Sustained Unresponsiveness Following Peanut Oral Immunotherapy is Linked to The Frequency of Granzyme B+ Memory CD8+ T Cells

Participants successfully desensitized to peanut through the 2-year-long peanut OIT trial POISED were classified as sustained unresponsive (SU) vs. desensitized alone (DS) based upon oral peanut challenge outcome following a 3-month peanut avoidance period post-OIT. Mass cytometry-based phenotyping of PBMCs from these participants showed that a lower frequency of naïve CD8+ T cells positively associates with sustained unresponsiveness. We further probed CD8+ T cells from SU and DS participants to understand molecules and pathways influencing peanut tolerance.

Comparative Transcriptome Analysis Reveals Complex Physiological Response and Gene Regulation in Peanut Roots and Leaves under Manganese Toxicity Stress

Excess Manganese (Mn) is toxic to plants and reduces crop production. Although physiological and molecular pathways may drive plant responses to Mn toxicity, few studies have evaluated Mn tolerance capacity in roots and leaves. As a result, the processes behind Mn tolerance in various plant tissue or organ are unclear. The reactivity of peanut (Arachis hypogaea) to Mn toxicity stress was examined in this study. Mn oxidation spots developed on peanut leaves, and the root growth was inhibited under Mn toxicity stress. The physiological results revealed that under Mn toxicity stress, the activities of antioxidases and the content of proline in roots and leaves were greatly elevated, whereas the content of soluble protein decreased. In addition, manganese and iron ion content in roots and leaves increased significantly, but magnesium ion content decreased drastically. The differentially expressed genes (DEGs) in peanut roots and leaves in response to Mn toxicity were subsequently identified using genome-wide transcriptome analysis. Transcriptomic profiling results showed that 731 and 4589 DEGs were discovered individually in roots and leaves, respectively. Furthermore, only 310 DEGs were frequently adjusted and controlled in peanut roots and leaves, indicating peanut roots and leaves exhibited various toxicity responses to Mn. The results of qRT-PCR suggested that the gene expression of many DEGs in roots and leaves was inconsistent, indicating a more complex regulation of DEGs. Therefore, different regulatory mechanisms are present in peanut roots and leaves in response to Mn toxicity stress. The findings of this study can serve as a starting point for further research into the molecular mechanism of important functional genes in peanut roots and leaves that regulate peanut tolerance to Mn poisoning.

BSA-Seq Approach Identified Candidate Region and Diagnostic Marker for Chilling Tolerance of High Oleic Acid Peanut at Germination Stage

High oleic acid peanut (HOAP) is extensively embraced in China because of its high nutritional value and enhanced oxidative stability. However, its dissemination has been severely constrained in high altitude and high latitude areas due to chilling stress during sowing, resulting in significant yield loss in these regions. Despite the lack of understanding of the molecular mechanisms underlying low temperature germination (LTG) in HOAP, discovering the quantitative trait loci (QTL) that confer this trait will undoubtedly benefit breeding efforts. In the present study, we identified putative genomic regions and single nucleotide polymorphisms (SNPs) that govern LTG tolerance of HOAP in an F2 population derived from the cross of chilling-tolerant YH65 and chilling-sensitive FL14 using bulk segregant analysis (BSA). Analysis of ΔSNP-index and Euclidean distance (ED) value association pinpointed the overlapped region to a 2.29 Mb interval on chromosome A05. The candidate interval showed that 122 genes were significantly related to response to abiotic stress and plant–pathogen interaction. Furthermore, an SNP site associated with LTG tolerance was discovered. The SNP site was employed as a Kompetitive Allele Specific PCR (KASP) marker and validated in a universal peanut panel. These findings may provide valuable insight into the molecular mechanism underpinning LTG tolerance and facilitate marker-assisted selective breeding in HOAP.

Food-specific immunoglobulin A does not correlate with natural tolerance to peanut or egg allergens.

ImmunoglobulinA (IgA) is the predominant antibody isotype in the gut, where it regulates commensal flora and neutralizes toxins and pathogens. The function of food-specific IgA in the gut is unknown but is presumed to protect from food allergy. Specifically, it has been hypothesized that food-specific IgA binds ingested allergens and promotes tolerance by immune exclusion; however, the evidence to support this hypothesis is indirect and mixed. Although it is known that healthy adults have peanut-specific IgA in the gut, it is unclear whether children also have gut peanut-specific IgA. We found in a cohort of non-food-allergic infants (n=112) that there is detectable stool peanut-specific IgA that is similar to adult quantities of gut peanut-specific IgA. To investigate whether this peanut-specific IgA is associated with peanut tolerance, we examined a separate cohort of atopic children (n=441) and found that gut peanut-specific IgA does not predict protection from development of future peanut allergy in infants nor does it correlate with concurrent oral tolerance of peanut in older children. We observed higher plasma peanut-specific IgA in those with peanut allergy. Similarly, egg white-specific IgA was detectable in infant stools and did not predict egg tolerance or outgrowth of egg allergy. Bead-based epitope assay analysis of gut peanut-specific IgA revealed similar epitope specificity between children with peanut allergy and those without; however, gut peanut-specific IgA and plasma peanut-specific IgE had different epitope specificities. These findings call into question the presumed protective role of food-specific IgA in food allergy.

Systematic review of monotherapy with biologicals for children and adults with IgE-mediated food allergy.

BackgroundBiological therapies relieve symptoms in allergic inflammatory diseases so we systematically reviewed the evidence about whether biological monotherapy could benefit people with IgE‐mediated food allergy.MethodsWe searched six bibliographic databases from 1946 to 30 September 2021 for randomised and non‐randomised controlled trials about biological monotherapy in people with IgE‐mediated food allergy confirmed by oral food challenge. We used the Grading of Recommendations, Assessment, Development and Evaluation approach to narratively summarise findings from three trials with 118 participants. The studies were too heterogeneous and sparse to conduct meta‐analysis.ResultsWe included one randomised trial about etokimab, one about omalizumab and one about the discontinued TNX‐901. All were in people with peanut allergy in the USA, mostly aged 13+ years. There was a trend towards improved tolerance of peanut during treatment, with few side effects. However, we have very low certainty about the evidence due to the small number of trials and participants. No included trial reported on quality of life or cost‐effectiveness.ConclusionsThere is not yet enough certainty to support offering etokimab or omalizumab widely for food allergy. Clinicians may consider the merits for individuals, but large randomised trials with standardised measures are needed to confirm the safety, efficacy and most suitable candidates, doses and durations of treatment before more universal use.

The Mechanisms Underlying Salt Resistance Mediated by Exogenous Application of 24-Epibrassinolide in Peanut.

Peanut is one of the most important oil crops in the world, the growth and productivity of which are severely affected by salt stress. 24-epibrassinolide (EBL) plays an important role in stress resistances. However, the roles of exogenous EBL on the salt tolerance of peanut remain unclear. In this study, peanut seedlings treated with 150 mM NaCl and with or without EBL spray were performed to investigate the roles of EBL on salt resistance. Under 150 mM NaCl conditions, foliar application of 0.1 µM EBL increased the activity of catalase and thereby could eliminate reactive oxygen species (ROS). Similarly, EBL application promoted the accumulation of proline and soluble sugar, thus maintaining osmotic balance. Furthermore, foliar EBL spray enhanced the total chlorophyll content and high photosynthesis capacity. Transcriptome analysis showed that under NaCl stress, EBL treatment up-regulated expression levels of genes encoding peroxisomal nicotinamide adenine dinucleotide carrier (PMP34), probable sucrose-phosphate synthase 2 (SPS2) beta-fructofuranosidase (BFRUCT1) and Na+/H+ antiporters (NHX7 and NHX8), while down-regulated proline dehydrogenase 2 (PRODH). These findings provide valuable resources for salt resistance study in peanut and lay the foundation for using BR to enhance salt tolerance during peanut production.

Small RNA and Degradome Deep Sequencing Reveals the Roles of microRNAs in Peanut (Arachis hypogaea L.) Cold Response.

Cold stress is a major environmental factor that affects plant growth and development, as well as fruit postharvest life and quality. MicroRNAs (miRNAs) are a class of non-coding small RNAs that play crucial roles in various abiotic stresses. Peanuts (Arachis hypogaea L.), one of the most important grain legumes and source of edible oils and proteins, are cultivated in the semi-arid tropical and subtropical regions of the world. To date, there has been no report on the role of miRNAs in the response to cold stress in cultivated peanuts. In this study, we profiled cold-responsive miRNAs in peanuts using deep sequencing in cold-sensitive (WQL20) alongside a tolerant variety (WQL30). A total of 407 known miRNAs and 143 novel peanut-specific miRNAs were identified. The expression of selected known and novel miRNAs was validated by northern blotting and six known cold-responsive miRNAs were revealed. Degradome sequencing identified six cold-responsive miRNAs that regulate 12 target genes. The correlative expression patterns of several miRNAs and their target genes were further validated using qRT-PCR. Our data showed that miR160-ARF, miR482-WDRL, miR2118-DR, miR396-GRF, miR162-DCL, miR1511-SRF, and miR1511-SPIRAL1 modules may mediate cold stress responses. Transient expression analysis in Nicotiana benthamiana found that miR160, miR482, and miR2118 may play positive roles, and miR396, miR162, and miR1511 play negative roles in the regulation of peanut cold tolerance. Our results provide a foundation for understanding miRNA-dependent cold stress response in peanuts. The characterized correlations between miRNAs and their response to cold stress could serve as markers in breeding programs or tools for improving cold tolerance of peanuts.

Basophil Activation Test Utility as a Diagnostic Tool in LTP Allergy.

Plant-food allergy is an increasing problem, with nonspecific lipid transfer proteins (nsLTPs) triggering mild/severe reactions. Pru p 3 is the major sensitizer in LTP food allergy (FA). However, in vivo and in vitro diagnosis is hampered by the need for differentiating between asymptomatic sensitization and allergy with clinical relevance. The basophil activation test (BAT) is an ex vivo method able to identify specific IgE related to the allergic response. Thus, we aimed to establish the value of BAT in a precise diagnosis of LTP-allergic patients. Ninety-two individuals with peach allergy sensitized to LTP, Pru p 3, were finally included, and 40.2% of them had symptoms to peanut (n = 37). In addition, 16 healthy subjects were recruited. BAT was performed with Pru p 3 and Ara h 9 (peanut LTP) at seven ten-fold concentrations, and was evaluated by flow cytometry, measuring the percentage of CD63 (%CD63+) and CD203c (%CD203chigh) cells, basophil allergen threshold sensitivity (CD-Sens), and area under the dose–response curve (AUC). Significant changes in BAT parameters (%CD63+ and %CD203chigh) were found between the controls and patients. However, comparisons for %CD63+, %CD203chigh, AUC, and CD-Sens showed similar levels among patients with different symptoms. An optimal cut-off was established from ROC curves, showing a significant positive percentage of BAT in patients compared to controls and great values of sensitivity (>87.5%) and specificity (>85%). In addition, BAT showed differences in LTP-allergic patients tolerant to peanut using its corresponding LTP, Ara h 9. BAT can be used as a potential diagnostic tool for identifying LTP allergy and for differentiating peanut tolerance, although neither reactivity nor sensitivity can distinguish the severity of the clinical symptoms.

Evaluating herbicide programs for peanut response and weed control

AbstractField research evaluated peanut (Arachis hypogaea L.) tolerance and weed control with preemergence (PRE) followed by early postemergence (EPOST) herbicide programs: PRE pyroxasulfone, S‐metolachlor, flumioxazin, pendimethalin, ethalfluralin, diclosulam, or dimethenamid‐P, followed by EPOST application of paraquat + acetochlor + bentazon at 4 wk after PRE (WA‐PRE). The herbicides resulted in no differences in peanut injury at 2 WA‐PRE in 2019 but flumioxazin resulted in approximately two‐fold greater injury (&gt;22%) than other treatments in 2020 because of heavy rainfall at peanut cracking. Palmer amaranth (Amaranthus palmeri S.Watson) control with diclosulam was lower than with other herbicides. Carpetweed (Mollugo verticillata L.) control with S‐metolachlor and dimethenamid‐P was at least 10% lower than with pendimethalin, flumioxazin, or pyroxasulfone at 4 WA‐PRE. Palmer amaranth control 2 wk after the EPOST (WA‐EPOST) application was &gt;94% for all treatments except diclosulam. Peanut injury at 2 WA‐EPOST was ≤28% but was minimal by 8 WA‐EPOST. Overall, yield with herbicide treatments was similar to the weedfree control. A greenhouse experiment evaluated postemergence herbicide combinations for Palmer amaranth control, including 2,4‐DB, acifluorfen, imazapic, bentazon + acifluorfen, pyroxasulfone + carfentrazone, and various combinations of each. Palmer amaranth control (≥99%) was greater and biomass (≤0.3 g plant–1) was lower with acifluorfen treatments than with other treatments. The 2,4‐DB + pyroxasulfone + carfentrazone treatment provided similar control to acifluorfen treatments. The EPOST paraquat + acetochlor + bentazon combinations following an effective PRE program will effectively control Palmer amaranth in peanut. Additionally, greenhouse experiments supported the use of acifluorfen for postemergence Palmer amaranth control.