Lower Disease Severity Research Articles

Genotypic characterization of novel S-DEL variants of porcine epidemic diarrhea virus identified in South Korea.

The highly pathogenic genotype 2b (HP-G2b) of porcine epidemic diarrhea virus (PEDV), which caused a pandemic in 2013-2014, evolved in South Korea and became endemic, affecting the domestic pig industry. This study describes the genotypic traits of novel HP-G2b PEDV strains identified on affected farms experiencing low disease severity with < 10% neonatal mortality. Nucleotide sequencing revealed common deletion patterns, termed S-DEL2, resulting in a two-amino-acid deletion at positions 60 and 61, 61 and 62, or 63 and 64 in the N-terminal domain of the spike (S) protein of all isolates. The S barcode profiles of S-DEL2 variants differed from each other and shared 96.0-99.4% and 98.5-99.6% nt sequence identity with other South Korean HP-G2b PEDV strains in the S gene and in the complete genome sequence, respectively. Genetic and phylogenetic analysis showed that the S-DEL2 strains belonged to diverse domestic clades: CK, CK.1, CK.2, or NC. The emergence of novel S-DEL2 strains suggests that continuous evolution of PEDV occurs under endemic circumstances, resulting in genetic diversity and distinct clinical presentations. This study advances our knowledge regarding the genetic and pathogenic heterogeneity of PEDV and emphasizes the importance of active monitoring and surveillance to identify novel variants and determine their genotypic and phenotypic characteristics.

Biological control of soybean charcoal rot by native Trichoderma koningiopsis in Tucumán, Argentina

Macrophomina phaseolina (Tassi) Goid. (Mp) is the causal agent of charcoal rot in soybean, an economically serious and potentially destructive disease. Chemical control sometimes has limited effects on disease severity and may pose a threat to the environment, so the use of Trichoderma as a biological product could be a feasible alternative for charcoal rot management. The objective of this research was to isolate and characterize native Trichoderma spp. from northwestern Argentina and study their antagonistic effect against Mp in soybean. Isolations were performed from soil samples followed by cultural and microbiological characterization of the Trichoderma spp. isolates collected. Then, the antagonist effect against Mp was studied in vitro, under greenhouse conditions, and finally under field conditions with pathogen artificial inoculations during two soybean crop seasons (2020 and 2021). The results demonstrated that isolate Tr009 had a biocontrol effect against Mp in soybean. This control was evidenced in vitro and under controlled and field conditions with high emergency of plants compared to the Mp inoculated control. Under field conditions, treatments that included Trichoderma presented lower disease severity, colony-forming unit index and disease severity index values than the pathogen inoculated control. Moreover, Tr009 improved weight and length of soybean plants under greenhouse conditions. Isolate Tr009 was identified as Trichoderma koningiopsis by molecular methods. These results indicate that this biological tool can be used against Mp and thus favor a sustainable management of soybean charcoal rot.

Maize insensitivity to culture filtrates from Exserohilum turcicum is related to quantitative resistance

AbstractTurcicum leaf blight (TLB) of maize is caused by Exserohilum turcicum. The TLB resistance is mainly associated with qualitative race‐specific resistance that is linked to several Ht genes namely Ht1, Ht2, Ht3, HtM, HtN, HtNB and HtP. However, quantitative TLB resistance also occurs, but its mechanisms are poorly understood. In this study, tolerance or insensitivity to chlorosis and necrosis of E. turcicum culture filtrate was associated with quantitative TLB resistance. A novel detached maize seedling assay was developed for E. turcicum culture filtrate using methanol‐treated modified Fries medium. Screening of E. turcicum isolates of races 2, 3, 23, 3 N, 23 N and 123 N against 61 maize inbred lines with diverse levels of resistance to TLB was conducted in the greenhouse by fungal inoculation and the detached seedling culture filtrate assay. Using an isolate of race 123 N, which can overcome all the qualitative resistance genes, a simple linear regression model (R2 = 0.68, p = .90) for the 61 inbred lines was established between disease severity from foliar inoculations and culture filtrate symptom rating of the detached seedling assay. Two maize lines CML474 and CML483 had relatively high culture filtrate symptom ratings but very low disease severity with foliar inoculation indicating that these sources of quantitative TLB resistance may be unrelated to tolerance to E. turcicum culture filtrates, whose effect on seedlings could be due to the toxin known as HT‐toxin or monocerin.

Metabolic Comorbidities in Pediatric Psoriasis-A Comparative Cross-Sectional Study in South-Asian Children.

There is only limited data on the association between psoriasis and metabolic comorbidities in South-Asian children. To examine metabolic comorbidities among South-Asian children with and without psoriasis. A hospital-based, comparative, cross-sectional study was conducted in children with and without psoriasis over 19 months. Anthropometric, clinical, and metabolic comorbidity details (including disease extent and severity scores, obesity, systemic hypertension, diabetes mellitus, lipid abnormalities, and metabolic syndrome) were obtained in both groups according to standard criteria. Fifty-eight children with psoriasis (25 males/33 females, age 11.3 ± 3.0 years, range 4 to 17 years) and 62 children without psoriasis (37 males/25 females, age 11.0 ± 3.6 years, range 4 to 18 years) were recruited. The prevalence of obesity (31.0% versus 14.5%, P = 0.031, odds ratio 2.65) and metabolic syndrome (18.6% versus 4.6%, P = 0.044, odds ratio 4.68) were higher in children with psoriasis than without. The prevalence of other metabolic comorbidities (systemic hypertension, pre-diabetes, lipid abnormalities, elevated serum alanine aminotransferase, and non-alcoholic fatty liver disease) was not different between children with and without psoriasis and between obese and non-obese children with psoriasis. Among children with psoriasis, those with abdominal obesity had significantly lower disease severity and extent scores than those without. Psoriasis is associated with a significantly higher prevalence of obesity and close to significantly higher prevalence of metabolic syndrome in South-Asian children. Screening for metabolic comorbidities is essential even in non-obese children with psoriasis. Disease extent and severity are less in obese compared to non-obese South-Asian children with psoriasis.

Functional analysis of the key BrSWEET genes for sugar transport involved in the Brassica rapa-Plasmodiophora brassicae interaction

Plasmodiophora brassicae, the causative agent of clubroot disease, establishes a long-lasting parasitic relationship with its host by inducing the expression of sugar transporters. Previous studies have indicated that most BrSWEET genes in Chinese cabbage are up-regulated upon infection with P. brassicae. However, the key BrSWEET genes responsive to P. brassicae have not been definitively identified. In this study, we selected five BrSWEET genes and conducted a functional analysis of them. These five BrSWEET genes showed a notable up-regulation in roots after P. brassicae inoculation. Furthermore, these BrSWEET proteins were localized to the plasma membrane. Yeast functional complementation assays confirmed transport activity for glucose, fructose, or sucrose in four BrSWEETs, with the exception of BrSWEET2a. Mutants and silenced plants of BrSWEET1a, -11a, and -12a showed lower clubroot disease severity compared to wild-type plants, while gain-of-function Arabidopsis thaliana plants overexpressing these three BrSWEET genes exhibited significantly higher disease incidence and severity. Our findings suggested that BrSWEET1a, BrSWEET11a, and BrSWEET12a play pivotal roles in P. brassicae-induced gall formation, shedding light on the role of sugar transporters in host-pathogen interactions.

Phosphate level predicts mortality in acute kidney injury patients undergoing continuous kidney replacement therapy and has a U-shaped association with mortality in patients with high disease severity: a multicenter retrospective study.

This study investigated the association between serum phosphate level and mortality in acute kidney injury (AKI) patients undergoing continuous kidney replacement therapy (CKRT) and evaluated whether this association differed according to disease severity. Data from eight tertiary hospitals in Korea were retrospectively analyzed. The patients were classified into four groups (low, normal, high, and very high) based on their serum phosphate level at baseline. The association between serum phosphate level and mortality was then analyzed, with further subgroup analysis being conducted according to disease severity. Among the 3,290 patients identified, 166, 955, 1,307, and 862 were in the low, normal, high, and very high phosphate groups, respectively. The 90-day mortality rate was 63.9% and was highest in the very high group (76.3%). Both the high and very high groups showed a significantly higher 90-day mortality rate than did the normal phosphate group (high: hazard ratio [HR], 1.35, 95% confidence interval [CI], 1.21-1.51, p < 0.001; very high: HR, 2.01, 95% CI, 1.78-2.27, p < 0.001). The low group also exhibited a higher 90-day mortality rate than did the normal group among those with high disease severity (HR, 1.47; 95% CI, 1.09-1.99; p = 0.01) but not among those with low disease severity. High serum phosphate level predicted increased mortality in AKI patients undergoing CKRT, and low phosphate level was associated with increased mortality in patients with high disease severity. Therefore, serum phosphate levels should be carefully considered in critically ill patients with AKI.

Native bacterial bioagents for management of potato soft rot disease caused by Pectobacterium carotovorum subsp. carotovorum

BackgroundThe reduced rate of potato production may occur under different conditions such as field, transit, storage, and marketing. Potato cultivation is frequently affected by various pathogens, among which Pectobacterium carotovorum subsp. carotovorum is a notorious bacterial pathogen responsible for causing bacterial soft rot disease. This pathogen poses a significant threat to potato production worldwide, resulting in substantial economic losses and food security concerns. This study aimed to investigate the effectiveness of three bacterial bioagents, namely Brevundimonas bullata, Bacillus siamensis, and Bacillus velezensis, against P. carotovorum subsp. carotovorum, a notorious bacterium responsible for causing potato tuber soft rot disease.ResultsFifteen isolates were isolated from rhizosphere of potato plants. Out of 15 isolates, 3 isolates, No. 1, 11, and 12, showed highly antagonistic property to control the growth of P. carotovorum subsp. carotovorum in vitro. They were identified as B. bullata, B. velezensis, and B. siamensis, by using 16S rRNA nucleotide sequence analysis. Results from these experiments revealed that three bioagents exhibited notable inhibitory effects on the growth of the pathogenic bacterium. However, B. velezensis stood out as the most effective inhibitor among the tested bioagents, showcasing the highest level of bacteriostatic activity (2.6 cm). The findings from the in vitro experiments provided promising insights into the potential of these bacterial bioagents as natural antagonists against potato tuber soft rot disease. Building upon these promising results, the study recommended the utilization of all tested bioagents for controlling soft rot disease in potato tubers, especially during storage conditions where the risk of bacterial proliferation is heightened. Treatment with B. bullata, B. siamensis, and B. velezensis demonstrates varying degrees of efficacy in controlling the progression of soft rot disease. Notably, B. velezensis shows promising results with relatively low disease severity scores across all time points compared to the other treatments. B. velezensis demonstrates the lowest disease severity percentage at 7.00% compared to the other treatments.ConclusionsThe study underscores the significant potential of B. bullata, B. siamensis, and B. velezensis as effective biological control agents against potato tuber soft rot disease. By targeting the causative agent directly, these bioagents offer a promising avenue for mitigating the detrimental impact of soft rot disease on potato production, thereby contributing to improved crop yield and quality.

Resistance of bread wheat (Triticum aestivum L.) varieties to fusarium head blight (Fusarium graminearum) in Ethiopia

AbstractFusarium head blight (FHB) is a devastating disease reduces wheat yield and quality. This study was aimed to evaluate wheat varieties' responses to spray inoculation with Fusarium graminearum mixture isolates under greenhouse conditions. The treatments were laid out in a randomized completely block design with three replications using 24 bread wheat varieties registered in Ethiopia. The varieties inoculated with mixed inoculum derived from four pathogenic isolates of F. graminearum that had been isolated from wheat kernels. Disease severity was evaluated using a 1–9 scale based on the proportion of bleached spikelets, and the area under disease progress curve (AUDPC) was determined from the disease severity data. At harvest, the kernel weight reduction was determined in comparison to the control. The evaluated traits were significantly interrelated and showed high and significant variation among (p &lt; 0.0001) wheat varieties. Disease severity index among the varieties varied from 29% to 72%, while AUDPC varied from 326%‐ to 1010%‐days. The disease progress rate of the Kingbird variety inoculated with F. graminearum was the slowest (0.0191 units day−1), whereas Ogolcho had the fastest disease progression rate (0.0581 units day−1). Kingbird, Wane, and Limu were moderately resistant, with lower disease severity, AUDPC, and a reduction in 1000‐grain weight and grain weight per spike. Dereselgne, Dambal, and Ogolcho varieties were highly susceptible, with the greatest grain weight per spike reduction (53.2%, 41.4%, and 37.4%) and 1000‐grain weight reduction (41.5%, 42.8%, and 37.5%), respectively. The results implied that there were different levels of FHB resistance in Ethiopian bread wheat varieties. Although current greenhouse evaluation of varieties gives encouraging results, field testing is required to confirm the current findings.

Clinical characteristics and outcomes of COVID-19 in children and adolescents with diabetes in Daegu, South Korea.

Children with comorbidities have a higher risk of severe, coronavirus disease 2019 (COVID-19). This study investigated the clinical features and outcomes of COVID-19 in children and adolescents with diabetes between January and March 2022. We retrospectively reviewed the medical records of 123 children and adolescents (73 with type 1 diabetes and 50 with type 2 diabetes, 59 males and 64 females) aged <18 years who had been diagnosed with diabetes. Data were collected from 7 academic medical centers in Daegu, South Korea. Thirty-five children with diabetes were diagnosed with COVID-19 (18 with type 1 and 17 with type 2 diabetes). Eighteen of the 35 children with diabetes and COVID-19 and 50 of the 88 children with diabetes alone received a COVID-19 vaccination. No significant differences were observed between patients with diabetes and COVID-19 and patients with diabetes alone in the type of diabetes diagnosed, sex, age, body mass index, hemoglobin A1c, or vaccination status. All children with diabetes and COVID-19 had mild clinical features and were safely managed in their homes. Fourteen children had a fever of 38℃ or higher that lasted for more than 2 days, 11 of whom were not vaccinated (p=0.004). None experienced post-COVID-19 conditions. All children and adolescents with pre-existing diabetes had mild symptoms of COVID-19 due to low disease severity, high vaccination rates, uninterrupted access to medical care, and continuous glucose monitoring. Unvaccinated children with diabetes who experienced COVID-19 presented with higher and more frequent fevers compared to vaccinated children.

Highly diverse sputum microbiota correlates with the disease severity in patients with community-acquired pneumonia: a longitudinal cohort study

BackgroundCommunity-acquired pneumonia (CAP) is a common and serious condition that can be caused by a variety of pathogens. However, much remains unknown about how these pathogens interact with the lower respiratory commensals, and whether any correlation exists between the dysbiosis of the lower respiratory microbiota and disease severity and prognosis.MethodsWe conducted a retrospective cohort study to investigate the composition and dynamics of sputum microbiota in patients diagnosed with CAP. In total, 917 sputum specimens were collected consecutively from 350 CAP inpatients enrolled in six hospitals following admission. The V3-V4 region of the 16 S rRNA gene was then sequenced.ResultsThe sputum microbiota in 71% of the samples were predominately composed of respiratory commensals. Conversely, 15% of the samples demonstrated dominance by five opportunistic pathogens. Additionally, 5% of the samples exhibited sterility, resembling the composition of negative controls. Compared to non-severe CAP patients, severe cases exhibited a more disrupted sputum microbiota, characterized by the highly dominant presence of potential pathogens, greater deviation from a healthy state, more significant alterations during hospitalization, and sparser bacterial interactions. The sputum microbiota on admission demonstrated a moderate prediction of disease severity (AUC = 0.74). Furthermore, different pathogenic infections were associated with specific microbiota alterations. Acinetobacter and Pseudomonas were more abundant in influenza A infections, with Acinetobacter was also enriched in Klebsiella pneumoniae infections.ConclusionCollectively, our study demonstrated that pneumonia may not consistently correlate with severe dysbiosis of the respiratory microbiota. Instead, the degree of microbiota dysbiosis was correlated with disease severity in CAP patients.

Optimizing maintenance therapy in responders to abrocitinib induction: A post hoc analysis of JADE REGIMEN.

Treatment optimization may require dosing flexibility. The Phase 3 JADE REGIMEN trial (NCT03627767) evaluated maintenance of abrocitinib 200 mg-induced response in patients with moderate-to-severe atopic dermatitis (AD) randomly assigned to subsequent maintenance with continuous-dose abrocitinib (200 mg), reduced-dose abrocitinib (100 mg) or placebo. Maintenance with continuous-dose abrocitinib was associated with a stronger prevention of disease flares, but also with a higher occurrence of adverse events, compared with the reduced dose. This post hoc analysis of JADE REGIMEN aimed to identify predictors of not flaring during the maintenance period and to generate tools that can be used to assess probability of not flaring. Data were analysed from patients who responded to abrocitinib 200 mg induction therapy (12 weeks) and were randomly assigned to receive abrocitinib (200 mg or 100 mg) or placebo in the 40-week maintenance period. Demographic and baseline disease characteristics and level of response to induction were evaluated for association with not flaring using logistic regression. Parameters with a significant (p < 0.15) interaction with the treatment arm were fitted into a multivariable regression model, which was used to assess probability of not flaring. Lower percentage body surface area affected at baseline (p = 0.09), absence of prior exposure to systemic agents (p = 0.02) and greater percentage change in EASI from baseline to randomization (p < 0.001) were identified as predictors of not flaring with abrocitinib. In both abrocitinib arms, percentage change in EASI from baseline to end of induction (Week 12) was the major contributor to the probability of not flaring in the maintenance period. Maintenance of response using reduced-dose abrocitinib 100 mg may be feasible for patients with lower baseline disease severity and strong response to abrocitinib 200 mg induction treatment.

Cytokine profiles associated with disease severity and prognosis of autoimmune pulmonary alveolar proteinosis

BackgroundPulmonary alveolar proteinosis (PAP) is characterized by an abnormal accumulation of surfactants in the alveoli. Most cases are classified as autoimmune PAP (APAP) because they are associated with autoantibodies against granulocyte-macrophage colony-stimulating factor (GM-CSF). However, GM-CSF autoantibody levels are unlikely to correlate with the disease severity or prognosis of APAP. MethodsWe collected clinical records and measured 38 serum cytokine concentrations for consecutive patients with APAP. After exclusion of 21 cytokines because of undetectable levels, 17 cytokine levels were compared between low and high disease severity scores (DSSs). We also compared whole lung lavage (WLL)-free survival with cut-off values defined by receiver operating characteristic (ROC) curves of cytokine levels and WLL administration at 11 months. ResultsNineteen patients with APAP were enrolled in the study. Five were classified as DSS 1 or 2, while the others were classified as DSS 4 or 5. Comparison between DSS 1−2 and 4−5 revealed that the concentrations of IP-10 and GRO increased in the latter groups (p < 0.05). Fifteen patients underwent WLL. Comparison between those who underwent WLL within 11 months and the others showed that IP-10 and TNF-α were tended to be elevated in the former group (p = 0.082 and 0.057, respectively). The cut-off values of IP-10, 308.8 pg/mL and TNF-α, 19.1 pg/mL, defined by the ROC curves, significantly separated WLL-free survivals with log-rank analyses (p = 0.005). ConclusionsThe concentrations of IP-10 and GRO may reflect the DSSs of APAP. A combination of IP-10 and TNF-α levels could be a biomarker to predict WLL-free survival.

Evasive Spike Variants Elucidate the Preservation of T Cell Immune Response to the SARS-CoV-2 Omicron Variant.

The Omicron variants boast the highest infectivity rates among all SARS-CoV-2 variants. Despite their lower disease severity, they can reinfect COVID-19 patients and infect vaccinated individuals as well. The high number of mutations in these variants render them resistant to antibodies that otherwise neutralize the spike protein of the original SARS-CoV-2 spike protein. Recent research has shown that despite its strong immune evasion, Omicron still induces strong T Cell responses similar to the original variant. This work investigates the molecular basis for this observation using the neural network tools NetMHCpan-4.1 and NetMHCiipan-4.0. The antigens presented through the MHC Class I and Class II pathways from all the notable SARS-CoV-2 variants were compared across numerous high frequency HLAs. All variants were observed to have equivalent T cell antigenicity. A novel positive control system was engineered in the form of spike variants that did evade T Cell responses, unlike Omicron. These evasive spike proteins were used to statistically confirm that the Omicron variants did not exhibit lower antigenicity in the MHC pathways. These results suggest that T Cell immunity mounts a strong defense against COVID-19 which is difficult for SARS-CoV-2 to overcome through mere evolution.

Breakthrough Mpox Outbreak Investigation, the Delicate Balance Between Host Immune Response and Viral Immune Escape.

Limited data are available on Mpox breakthrough infections. The purpose of this study is to investigate a Mpox breakthrough outbreak in 3 vaccinated individuals. Study participants provided informed consent. Serology testing was performed in one involved individual (ID-1) using an in-house assay detecting anti-orthopoxvirus IgG. Whole genome sequencing (WGS) was carried out and compared with the reference sequence ON563414.3 ( https://www.ncbi.nlm.nih.gov/nuccore/ON563414.3/ ). Three individuals vaccinated with modified vaccinia Ankara-Bavaria Nordic contracted Mpox following one sexual intercourse event. One of them (ID-1) had received only one vaccine dose, while the other two were fully vaccinated. ID-1 presented to the sexual health clinic of the Universitair Ziekenhuis Brussel with proctitis related to Mpox. Despite one vaccination, serology testing Three months post vaccine showed absence of Mpox virus (MPXV) specific antibodies in ID-1. In contrast, 2 weeks after the sexual intercourse, seroconversion occurred. Whole genome sequencing of the isolated MPXV showed, compared with the reference sequence, a total of seven single nucleotide variants with four of them indicating protein amino-acid changes. Incomplete MPXV vaccination as well as MPXV variants might result in breakthrough infections. Preventive measures, such as MPVX vaccination, could maintain immunity in individuals with higher risk of MPXV infection, and might lower disease severity.

Systemic Inflammatory Response Index, a Potential Inflammatory Biomarker in Disease Severity of Myasthenia Gravis: A Pilot Retrospective Study.

Myasthenia gravis (MG) is a chronic autoimmune disease caused by neuromuscular junction (NMJ) dysfunction. Our current understanding of MG's inflammatory component remains poor. The systemic inflammatory response index (SIRI) presents a promising yet unexplored biomarker for assessing MG severity. This study aimed to investigate the potential relationship between SIRI and MG disease severity. We conducted a retrospective analysis of clinical data from 171 MG patients admitted between January 2016 and June 2021. Patients with incomplete data, other autoimmune diseases, or comorbidities were excluded. Disease severity was evaluated using the Myasthenia Gravis Foundation of America (MGFA) classification and Myasthenia Gravis Activities of Daily Living (MG-ADL) on admission. The association between SIRI and disease severity was assessed through logistic regression analysis, along with receiver operating characteristic (ROC) curve and decision curve analysis (DCA) comparisons with established inflammation indicators. After exclusion, 143 patients were analyzed in our study. SIRI levels significantly differed between patients with higher and lower disease severity (p < 0.001). Univariate logistic regression showed that SIRI had a significant effect on high disease severity (OR = 1.376, 95% CI 1.138-1.664, p = 0.001). This association remained significant even after adjusting for age, sex, disease duration, history of MG medication and thymoma (OR = 1.308, 95% CI 1.072-1.597, p = 0.008). Additionally, a positive correlation between SIRI and MG-ADL was observed (r = 0.232, p = 0.008). Significant interactions were observed between SIRI and immunosuppressor (p interaction = 0.001) and intravenous immunoglobulin (p interaction = 0.005). DCA demonstrated the superior net clinical benefit of SIRI compared to other markers when the threshold probability was around 0.2. Our findings indicate a strong independent association between SIRI and disease severity in MG, suggesting SIRI's potential as a valuable biomarker for MG with superior clinical benefit to currently utilized markers.

Mapping and validation of Fusarium wilt race 2 resistance QTL from Citrullus amarus line USVL246-FR2

Key messageFon race 2 resistant QTLs were identified on chromosomes 8 and 9. Families homozygous for resistance alleles at a haplotype of three KASP markers had 42% lower disease severity than those with susceptible alleles in an independent, interspecific validation population confirming their utility for introgression of Fusarium wilt resistance.Fusarium oxysporum f. sp. niveum (Fon) race 2 causes Fusarium wilt in watermelon and threatens watermelon production worldwide. Chemical management options are not effective, and no resistant edible watermelon cultivars have been released. Implementation of marker-assisted selection to develop resistant cultivars requires identifying sources of resistance and the underlying quantitative trait loci (QTL), developing molecular markers associated with the QTL, and validating marker-phenotype associations with an independent population. An intraspecific Citrullus amarus recombinant inbred line population from a cross of resistant USVL246-FR2 and susceptible USVL114 was used for mapping Fon race 2 resistance QTL. KASP markers were developed (N = 51) for the major QTL on chromosome 9 and minor QTL on chromosomes 1, 6, and 8. An interspecific F2:3 population was developed from resistance donor USVL246-FR2 (C. amarus) and a susceptible cultivar ‘Sugar Baby’ (Citrullus lanatus) to validate the utility of the markers for introgression of resistance from the wild crop relative into cultivated watermelon. Only 16 KASP markers segregated in the interspecific C. amarus/lanatus validation population. Four markers showed significant differences in the separation of genotypes based on family-mean disease severity, but together explained only 16% of the phenotypic variance. Genotypes that inherited homozygous resistant parental alleles at three KASP markers had 42% lower family-mean disease severity than homozygous susceptible genotypes. Thus, haplotype analysis was more effective at predicting the mean disease severity of families than single markers. The haplotype identified in this study will be valuable for developing Fon race 2 resistant watermelon cultivars.

Soil amendments with nanoparticles control cucumber wilt caused by Fusarium oxysporium

Management of Fusarium wilt, a destructive plant disease, mainly relies on chemicals, but research on novel and eco-friendly methods is needed due to the hazardous effects of chemical pesticides. This study explored the soil application of zinc oxide nanoparticles (ZnONPs) to manage Fusarium wilt disease in cucumber plants. The antifungal activity of ZnONPs against in-vitro growth of Fusarium oxysporum was tested through food poisoning test on the potato dextrose agar medium. The in-vivo potential of NPs for managing Fusarium wilt was checked in pot experiment. In-vitro results confirmed the concentration-dependent in-vitro antifungal activity. The NPs application at 500 µg/ml and 600 µg/ml concentrations showed phytotoxicity and significantly inhibited seed germination and growth of cucumber plants. However, NPs at 300 µg/ml significantly suppressed the pathogenic effects of F. oxysporum on cucumber plants without any phytotoxic effect. The pathogen-inoculated cucumber plants grown in soil amended with NPs showed significantly enhanced growth, lower disease severity, and improved root physiology compared to untreated plants. The plants under NPs treatment showed higher chlorophyll and nitrogen content while decreased membrane permeability and malondialdehyde content. Along with direct antifungal activity, the application of NPs caused an increased expression of defense-related genes and higher activities of defense-related enzymes. These findings verified the efficiency of ZnONPs for suppressing Fusarium wilt disease in cucumber crops, thereby promoting a non-chemical and environmentally friendly approach to controlling Fusarium wilt disease.

Immune and behavioral correlates of protection against symptomatic post-vaccination SARS-CoV-2 infection.

We sought to determine pre-infection correlates of protection against SARS-CoV-2 post-vaccine inzfections (PVI) acquired during the first Omicron wave in the United States. Serum and saliva samples from 176 vaccinated adults were collected from October to December of 2021, immediately before the Omicron wave, and assessed for SARS-CoV-2 Spike-specific IgG and IgA binding antibodies (bAb). Sera were also assessed for bAb using commercial assays, and for neutralization activity against several SARS-CoV-2 variants. PVI duration and severity, as well as risk and precautionary behaviors, were assessed by questionnaires. Serum anti-Spike IgG levels assessed by research assay, neutralization titers against Omicron subvariants, and low home risk scores correlated with protection against PVIs after multivariable regression analysis. Commercial assays did not perform as well as research assay, likely due to their lower dynamic range. In the 32 participants that developed PVI, anti-Spike IgG bAbs correlated with lower disease severity and shorter duration of illness.

Identification of Resistance to Target Spot of Tomato Caused by Corynespora cassiicola in Wild Tomato Accessions

Tomato (Solanum lycopersicum) is an important vegetable crop and a valuable source of nutrients for the human diet. The southeast is the main fresh market tomato producer of the United States, with much of the production concentrated in Florida. However, production in this region is threatened by plant diseases such as target spot of tomato (TS) caused by Corynespora cassiicola, a multitrophic fungus widely distributed in tropical and subtropical areas. TS can infect foliage and fruit, often resulting in significant yield losses in conductive environments. There are no known TS-resistant cultivars, and control relies entirely on fungicidal sprays. However, several studies have demonstrated that the fungus is developing resistance to commonly used fungicides which further complicates disease management. The objective of this work was to identify sources of resistance to TS from wild Solanum accessions. Initial screens of 83 accessions informed the selection of 24 accessions for a more robust screening in which six diverse C. cassiicola isolates were used for single-isolate inoculation experiments. The results from a broad-sense mixed-model analysis including data from all six experiments demonstrated that all 24 accessions had significantly lower disease severities compared with the susceptible controls, suggesting that all accessions potentially harbor resistance quantitative trait loci (QTLs). Solanum cheesmaniae accession LA0524, S. galapagense accessions LA0483 and LA0532, and S. pimpinellifolium accession LA2093 were among the most resistant accessions tested and may be particularly useful for introgression of resistance into cultivated germplasm and for mapping of TS resistance QTLs.

Early boosting of genetically improved Falcataria moluccana with mycorrhiza for better growth and disease tolerance

Falcataria moluccana is a widespread species that grows rapidly in Indonesia and produces timber used for carpentry. Nonetheless, this species is especially susceptible to gall rust disease. To find plants that can handle rust, a mix of breeding with progeny experiments and forest management methods, like arbuscular mycorrhiza (AM), were used. The point of this study is to find out if adding AM changes how F. moluccana seedlings grow and how they react to gall rust disease, both those that have been improved and those that have not. We will also look at the response by calculating the area under disease progress curves (AUDPC) value for rust disease to grow in F. moluccana seedlings. The experimental design comprised four different treatments, including varying quantities of mycorrhizae, as well as four different seed sources. For the mycorrhizal inoculation experiments, there was a control group and three treatment groups. The treatment groups got 5, 10, and 15 g of mycorrhiza per polybag, respectively. The seeds used in this study were sourced from two unimproved families, namely Java and Solomon, as well as two genetically improved families, F63 and F77. This study revealed that mycorrhizal application affects the growth of F. moluccana seedlings and significantly reduces both disease incidence and severity. The application of mycorrhiza reduces the disease incidence and severity; the AUPDC value of seedlings with mycorrhiza added is four times lower than that of seedlings without mycorrhiza. The disease severity was highest for the unimproved Solomon seedlings, despite the fact that the source of seeds had little impact on the disease incidence. Meanwhile, the genetically improved seedlings demonstrated lower disease incidence and severity rates than seedlings without improvement, with an AUPDC value nearly half that of the unimproved seedling. In terms of diameter and height, F. mollucana seedlings derived from various seed sources were remarkably diverse, and seedlings with improvements grew much better than seedlings without improvements. This study shows how arbuscular mycorrhiza affects how well improved and unimproved F. moluccana seedlings deal with gall rust disease.