Pseudomonas synxantha volatile organic compounds: efficacy against Cadophora luteo-olivacea and Botrytis cinerea of kiwifruit

Volatile organic compounds (VOCs) are responsible for the antagonistic activity exerted by different biological control agents (BCAs). In this study, VOCs produced by Pseudomonas synxantha strain 117-2b were tested against two kiwifruit fungal postharvest pathogens: Cadophora luteo-olivacea and Botrytis cinerea, through in vitro and in vivo assays. In vitro results demonstrated that P. synxantha 117-2b VOCs inhibit mycelial growth of C. luteo-olivacea and B. cinerea by 56% and 42.8% after 14 and 5 days of exposition, respectively. In vivo assay demonstrated significant inhibitory effects. VOCs used as a biofumigant treatment reduced skin-pitting symptoms disease severity by 28.5% and gray mold incidence by 66.6%, with respect to the untreated control. BCA volatiles were analyzed by solid-phase microextraction coupled with gas chromatography-mass spectrometry (SPME-GC/MS), and among the detected compounds, 1-butanol, 3-methyl and 1-nonene resulted as the most produced. Their efficacy as pure synthetic compounds was assayed against mycelial growth of fungal pathogens by different concentrations (0.34, 0.56, and 1.12 µL mL-1 headspace). The effect of the application of VOCs as a biofumigant was also investigated as the expression level of seven defense-related genes of kiwifruit at different exposition times. The results indicated an enhancement of the expression of almost all the genes starting from 3 h of treatment. These results described P. synxantha VOCs characteristics and their potential as a promising method to adopt for protecting kiwifruit from postharvest diseases caused by C. luteo-olivacea and B. cinerea.

The Oxford Nanopore MinION as a Versatile Technology for the Diagnosis and Characterization of Emerging Plant Viruses

The emergence of novel viral epidemics that could affect major crops represents a serious threat to global food security. The early and accurate identification of the causative viral agent is the most important step for a rapid and effective response to disease outbreaks. Over the last years, the Oxford Nanopore Technologies (ONT) MinION sequencer has been proposed as an effective diagnostic tool for the early detection and identification of emerging viruses in plants, providing many advantages compared with different high-throughput sequencing (HTS) technologies. Here, we provide a step-by-step protocol that we optimized to obtain the virome of "Lamon bean" plants (Phaseolus vulgaris L.), an agricultural product with Protected Geographical Indication (PGI) in North-East of Italy, which is frequently subjected to multiple infections caused by different RNA viruses. The conversion of viral RNA in ds-cDNA enabled the use of Genomic DNA Ligation Sequencing Kit and Native Barcoding DNA Kit, which have been originally developed for DNA sequencing. This allowed the simultaneous diagnosis of both DNA- and RNA-based pathogens, providing a more versatile alternative to the use of direct RNA and/or direct cDNA sequencing kits.

Methylation Analysis of Urinary Sample in Non-Muscle-Invasive Bladder Carcinoma: Frequency and Management of Invalid Result

BACKGROUND

Numerous studies showed that methylation analysis represents a newly developed urinary marker based on DNA methylation changes in a panel of genomic biomarkers and it could represent a valid tool in terms of the diagnosis and prediction of high-grade urothelial carcinoma recurrences. One of the limits of the use of this new molecular method during a follow-up is represented by the number of invalid tests in routine practice.

METHOD

A total of 782 patients with a diagnosis of non-muscle-invasive high-grade carcinoma (NMIBC) was studied. The Bladder EpiCheck test (BE) was performed together with cytology in all cases within 1 year after the end of treatment. In 402 patients, the urinary samples were voided urine (UV), while, in 380 cases, the samples were collected after bladder washing (IU). For all the patients with invalid BE results, a second BE test was performed following the instructions for use that indicated the test should be repeated with a new urinary sample in the case of an invalid result.

RESULTS

Analyzing the two different groups (UV and IU), we found the invalid BE results seemed to be not related to urinary samples (p = 0.13 Fisher's exact test), suggesting that the collection method was not relevant in order to reduce the number of invalid tests.

CONCLUSIONS

In the follow-up for NMIBC, for patients for whom a BE test is planned, a combined approach of cytology and a methylation test is recommended in order to repeat the BE test with an invalid result only in those cases with a cytological diagnosis of atypical urothelial cells (AUC) suspicious for high-grade urothelial carcinoma (SHGUC) and high-grade urothelial carcinoma (HGUC).

Sterol, tocopherol, and bioactive fatty acid differences between conventional, high-quality, and organic cow milk

Milk contains several components that are important for human nutrition and health. To date, studies on organic and conventional milk have focused on their gross composition and fatty acid content, but little attention has been paid to the differences between other minor components, such as sterols and vitamins that may have functional actions. The aim of this study was to investigate the nutritional differences among 3 types of milk from a dairy plant: conventional, high-quality, and organic (in compliance with European regulations) milk, focusing on minor components such as sterols of animal and plant origin (phytosterols), tocopherols, and bioactive fatty acids. Cholesterol ranged from 271.37 mg/100 g of fat in conventional milk to 278.76 mg/100 g of fat in organic milk. Lanosterol was the main minor animal sterol in cow milk (ranging from 3.41 to 4.37 mg/100 g of fat), followed by desmosterol. The amount of total plant sterols in the analyzed milk ranged from 4.43 mg/100 g of fat in organic to 4.71 mg/100 g of fat in high-quality milk. Brassicasterol was the main sterol of plant origin which varied from 2.6 mg/100 g of fat in conventional and organic milk, to 2.93 mg/100 g of fat in high-quality milk. The second most present phytosterol was β-sitosterol, which ranged from 0.86 mg/100 g of fat in conventional to 0.97 mg/100 g of fat in high-quality, and organic milk. The results of the study showed no significant differences in gross and sterol composition between the 3 types of milk. However, the only significant difference found was in the fatty acid profile, with a higher n-3 content found in high-quality milk than in conventional and organic milk. These findings suggest that the investigated product categories and labels have minimal effect on the sterol and fatty acid profile of commercial cow milk.

Genetic diversity of Actinidia spp. shapes the oomycete pattern associated with Kiwifruit Vine Decline Syndrome (KVDS)

Kiwifruit Vine Decline Syndrome (KVDS) is an important soil-borne disease for the Italian kiwifruit industry, causing €300,000 in economic losses in 2020 alone. So far, the organisms recognized as involved in the aetiology of KVDS mainly belong to the Oomycota. As no effective management strategies exist, a promising approach to overcoming KVDS is the use of resistant species as rootstocks or for inclusion in breeding programs. Several Actinidia genotypes showing different level of resistance to KVDS were grown in disease-promoting soils. A metabarcoding approach was set up to identify KVDS-associated oomycetes and investigate whether the main species involved may vary according to plant genotype. Our results clearly showed significant differences between the genotypes in terms of oomycetes present in both plant rhizosphere and endosphere, which were strongly correlated with the symptoms displayed. We found out that the resistance of Actinidia macrosperma to KVDS is related to its ability to shape the pathobiome, particularly as far as the endosphere is concerned. In our conditions, Phytophthora sp. was predominantly found in sensitive genotypes, whilst Globisporangium intermedium was mainly detected in asymptomatic plants, suggesting that the latter species could compete with the recruitment of Phytophthora sp. in plants with different levels of resistance, consequently, explaining the onset of symptoms and the resistance condition.

Measurements of neutrino oscillation parameters from the T2K experiment using 3.6×1021 protons on target

The T2K experiment presents new measurements of neutrino oscillation parameters using 19.7 ( 16.3 ) × 10 20 protons on target (POT) in (anti-)neutrino mode at the far detector (FD). Compared to the previous analysis, an additional 4.7 × 10 20 POT neutrino data was collected at the FD. Significant improvements were made to the analysis methodology, with the near-detector analysis introducing new selections and using more than double the data. Additionally, this is the first T2K oscillation analysis to use NA61/SHINE data on a replica of the T2K target to tune the neutrino flux model, and the neutrino interaction model was improved to include new nuclear effects and calculations. Frequentist and Bayesian analyses are presented, including results on sin 2 θ 13 and the impact of priors on the δ CP measurement. Both analyses prefer the normal mass ordering and upper octant of sin 2 θ 23 with a nearly maximally CP-violating phase. Assuming the normal ordering and using the constraint on sin 2 θ 13 from reactors, sin 2 θ 23 = 0 . 561 - 0.032 + 0.021 using Feldman-Cousins corrected intervals, and Δ m 32 2 = 2 . 494 - 0.058 + 0.041 × 10 - 3 eV 2 using constant Δ χ 2 intervals. The CP-violating phase is constrained to δ CP = - 1 . 97 - 0.70 + 0.97 using Feldman-Cousins corrected intervals, and δ CP = 0 , π is excluded at more than 90% confidence level. A Jarlskog invariant of zero is excluded at more than 2 σ credible level using a flat prior in δ CP , and just below 2 σ using a flat prior in sin δ CP . When the external constraint on sin 2 θ 13 is removed, sin 2 θ 13 = 28 . 0 - 6.5 + 2.8 × 10 - 3 , in agreement with measurements from reactor experiments. These results are consistent with previous T2K analyses.

Severe asthma: follow-up after one year from the Italian Registry on Severe Asthma (IRSA)

Summary

Background. Asthma affects millions of people worldwide, with a subgroup suffering from severe asthma (SA). Biologics have revolutionized SA treatment, but challenges remain in managing different patient traits. This study analyzed data from the Italian Registry on Severe Asthma (IRSA) to investigate changes in SA characteristics and effectiveness of treatments after one year of follow-up, and to identify factors associated with response to treatments in a real-world setting. Methods. Data on SA patients with one year of follow-up were extracted from IRSA. Asthma control, exacerbations, lung function, and treatments, were assessed at follow-up and analyzed against baseline characteristics. Results. After one year of follow-up, notable improvements were observed in all the outcomes of SA of the included patients (n = 570). The effectiveness of biologic therapies was particularly evident, as they contributed significantly to these positive outcomes. Additionally, certain factors were found to be associated with improvement, namely T2 phenotype, baseline eosinophil count (BEC), and area of residence. On the other hand, comorbidities (obesity, gastro-esophageal reflux disease) and poor lung function were risk factors. Notably, poor-responders to biologics exhibited lower level of education, BEC, and exacerbations, and higher frequency of atopy and ACT score ≥ 20. Conclusions. The findings demonstrate the effectiveness of biologics in asthma management, when implemented as part of a planned follow-up strategy aimed at optimizing and fine-tuning the therapy. Moreover, the study highlights the importance of considering key traits such as the T2 phenotype, BEC, education, and comorbidities when tailoring SA treatment. Overall, this study contributes to enhancing our understanding of SA management and guiding the development of personalized treatment approaches for patients with SA.

Aristotle - Ἀριστοτέλης (ARISTOTÉLĒS, 384/3- 322/1 BCE) The revelation of tuberculosis in his zoological works

One of the most challenging issues with the sources of ancient medicine is to be able to identify the correspondence between the diseases we know today and those reported in ancient medical texts. Ancient diseases' definitions rarely help us, and the symptoms described often correspond to more than one disease. This is especially true about tuberculosis, a disease that historians of medicine habitually associates with the Greek words phthi(n)o (φθίνω), verb, phthisis/phthoe (φθίσις/φθόη), noun, phthinodes/phthisikos (φθινώδης/φθισικός), adjective, all etymologically linked to an Indo-European root that expresses the idea of consumption in a broad sense. This article aims to analyze a group of Greek words, branchos/branchia (βράγχος/βράγχια), krauros/kraurao (κραῦρος/κραυράω), and katarreo (καταρρέω), that appear in nosological contexts very close to the infectious disease that today we call tuberculosis. Moreover, the paper aims to focus on the transmission pathways of TB being via animal-human contact and some ancient strategies to cure it. The symptoms, transmission pathways and therapeutic approach of tuberculosis belong to a homogeneous pathological picture that emerges from a set of texts that date back to the period between the fifth century BC and the second century AD.

COVID-19 lockdown, personal protective equipment, hyper-hygiene and allergy

Summary

At the beginning of SARS-CoV 2 pandemic, in the absence of "targeted" therapies, the national health authorities have introduced some measures aimed at reducing the spread of infection in the community (lockdown, social distancing, personal protective equipment (PPE), personal hygiene and disinfection of living environments). All the containment measures have led to both positive and negative effects in patients with allergic diseases. We believe that further studies should be undertaken to investigate the possible correlations between SARS-CoV-2 infection and allergy, from a broader perspective. In particular, the risk factors for the development of undesirable effects should be investigated, especially in healthcare professionals forced to use PPE and sanitizing agents for a long time. However, since the COVID-19 pandemic probably will not be short-lived, the use of such protective aids will necessarily be widespread even in the general population. Therefore, further studies on the materials used for the production of PPE and sanitizing agents would be necessary to reduce their sensitizing and, in some cases, toxic potential.

Protective effect of the tunneling nanotube-TNFAIP2/M-sec system on podocyte autophagy in diabetic nephropathy

Podocyte injury leading to albuminuria is a characteristic feature of diabetic nephropathy (DN). Hyperglycemia and advanced glycation end products (AGEs) are major determinants of DN. However, the underlying mechanisms of podocyte injury remain poorly understood. The cytosolic protein TNFAIP2/M-Sec is required for tunneling nanotubes (TNTs) formation, which are membrane channels that transiently connect cells, allowing organelle transfer. Podocytes express TNFAIP2 and form TNTs, but the potential relevance of the TNFAIP2-TNT system in DN is unknown. We studied TNFAIP2 expression in both human and experimental DN and the renal effect of tnfaip2 deletion in streptozotocin-induced DN. Moreover, we explored the role of the TNFAIP2-TNT system in podocytes exposed to diabetes-related insults. TNFAIP2 was overexpressed by podocytes in both human and experimental DN and exposre of podocytes to high glucose and AGEs induced the TNFAIP2-TNT system. In diabetic mice, tnfaip2 deletion exacerbated albuminuria, renal function loss, podocyte injury, and mesangial expansion. Moreover, blockade of the autophagic flux due to lysosomal dysfunction was observed in diabetes-injured podocytes both in vitro and in vivo and exacerbated by tnfaip2 deletion. TNTs allowed autophagosome and lysosome exchange between podocytes, thereby ameliorating AGE-induced lysosomal dysfunction and apoptosis. This protective effect was abolished by tnfaip2 deletion, TNT inhibition, and donor cell lysosome damage. By contrast, Tnfaip2 overexpression enhanced TNT-mediated transfer and prevented AGE-induced autophagy and lysosome dysfunction and apoptosis. In conclusion, TNFAIP2 plays an important protective role in podocytes in the context of DN by allowing TNT-mediated autophagosome and lysosome exchange and may represent a novel druggable target.Abbreviations: AGEs: advanced glycation end products; AKT1: AKT serine/threonine kinase 1; AO: acridine orange; ALs: autolysosomes; APs: autophagosomes; BM: bone marrow; BSA: bovine serum albumin; CTSD: cathepsin D; DIC: differential interference contrast; DN: diabetic nephropathy; FSGS: focal segmental glomerulosclerosis; HG: high glucose; KO: knockout; LAMP1: lysosomal-associated membrane protein 1; LMP: lysosomal membrane permeabilization; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; PI3K: phosphoinositide 3-kinase; STZ: streptozotocin; TNF: tumor necrosis factor; TNFAIP2: tumor necrosis factor, alpha-induced protein 2; TNTs: tunneling nanotubes; WT: wild type.

Vaccine hesitancy, misinformation in the era of Covid-19: Lessons from the past

Background

As the world has challenged/argued with the Covid-19 pandemic over the last two years, there has been an increase in vaccine misinformation. Although immunity against Covid-19 infection is limited to 4-6 months and requires at least three doses of vaccine to be maximally effective, the current vaccination campaign in industrialized countries shows that vaccinated citizens experience greater immunological protection against severe forms of the disease than unvaccinated citizens.

Methodology

A perusal of the literature was performed in order to reconstruct the communication methods applied in the managing of the Covid-19 pandemic; the management of the current pandemic was compared with the management of another scourge of the past: poliomyelitis.

Results/Discussion

In order to raise public awareness on public health issues, it is essential that governments and institutions communicate scientific data to all sections of the population in an unambiguous way. In this sense, it is essential to apply "prebunking", which is a layered defense system available to society that prevents misinformation before it is spread. This is to avoid the subsequent debunking of false information, which generates insecurity and fuels fears. Belief in medical misinformation represents a meaningful problem for public health efforts to fight Covid-19 through vaccination.

Conclusion/Perspectives

In this sense an example of proper management of one of the many epidemics of the recent past, poliomyelitis, should make us reflect on the effectiveness of past approaches. This testimony from the past can provide us with food for thought regarding how to face the present Covid-19 pandemic and to prepare for the future. Certainly, it shows us how the awful pandemics/epidemics from the past was handled and finally overcome, despite perceived risk and vaccine hesitancy.

P392 A MULTIMODALITY IMAGING DIAGNOSIS OF A CHALLENGING CASE OF CONCOMITANT GROUP 1 PULMONARY HYPERTENSION AND PARADOXICALLY LOW–FLOW, LOW–GRADIENT AORTIC STENOSIS

 

A 76 year old woman was admitted to our hospital for self–limiting dyspnoea (NYHA class III) in oxygen dependence and frequent lipothymia following Valsalva manoeuvres. She was previously admitted to a Spoke Centre for heart failure (HF) with preserved ejection fraction (EF) and a new diagnosis of “pre–capillary pulmonary hypertension (PH)”. Despite a diagnosis of PH of unclear aetiology, she was started on macitentan without being reassessed for functional capacity due to Covid emergency; because of worsening symptoms, she was admitted to our Hub Centre. Resting ECG showed right axis deviation, right ventricle (RV) hypertrophy, first–degree atrioventricular block and right bundle branch block. Transthoracic echocardiography (TTE) showed reduced left ventricular (LV) volume with preserved EF (diastolic volume= 37 ml, EF = 88%), severe right atrial and RV dilation with flattening of the interventricular septum, estimated pulmonary artery systolic pressure (PASP) of 124 mmHg, and moderate calcific aortic stenosis (peak aortic velocity 3.3 m/s, mean gradient 25 mmHg, valve area 1.1 cm2). Right and left heart catheterization showed severe pre–capillary PH (mean pulmonary pressure 60 mmHg, mean wedge 11 mmHg, pulmonary vascular resistance 14.41 WU), a severe aortic valve stenosis (aortic valve area 0.68 cmq and peak–to–peak gradient 25 mmHg, slight reduction of cardiac index 2.04 l/min/mq) and no significant coronary artery disease. The degree of aortic stenosis was considered as moderate–severe by integrating data of transesophageal echocardiography (planimetric area 1cm2) and assessment of calcium score (1615 Agatson units). Pneumological causes, chronic thromboembolic PH, rheumatologic diseases, HIV infection, paraneoplastic origin and veno–occlusive disease were all ruled out as potential PH causes and a diagnosis of Idiopathic pulmonary arterial hypertension (IPAH) was finally made. The Heart Team established the best therapeutic option was a transcatheter aortic valve replacement (TAVI) allowing better haemodynamic tolerability of PH therapy. The patient underwent TAVI and was started on PH therapy; a complete atrio–ventricular block developed after the procedure, requiring permanent pacemaker (PM) implantation. Unfortunately, few days later, the patient died following pacemaker’s lead dislocation.

Conclusion

PH has a diverse aetiology, and prognosis is generally poor, especially in patients with severe comorbidities.

Revision of the 'Candidatus Phytoplasma' species description guidelines

The genus 'Candidatus Phytoplasma' was proposed to accommodate cell wall-less bacteria that are molecularly and biochemically incompletely characterized, and colonize plant phloem and insect vector tissues. This provisional classification is highly relevant due to its application in epidemiological and ecological studies, mainly aimed at keeping the severe phytoplasma plant diseases under control worldwide. Given the increasing discovery of molecular diversity within the genus 'Ca. Phytoplasma', the proposed guidelines were revised and clarified to accommodate those 'Ca. Phytoplasma' species strains sharing >98.65 % sequence identity of their full or nearly full 16S rRNA gene sequences, obtained with at least twofold coverage of the sequence, compared with those of the reference strain of such species. Strains sharing <98.65 % sequence identity with the reference strain but >98.65 % with other strain(s) within the same 'Ca. Phytoplasma' species should be considered related strains to that 'Ca. Phytoplasma' species. The guidelines herein, keep the original published reference strains. However, to improve 'Ca. Phytoplasma' species assignment, complementary strains are suggested as an alternative to the reference strains. This will be implemented when only a partial 16S rRNA gene and/or a few other genes have been sequenced, or the strain is no longer available for further molecular characterization. Lists of 'Ca. Phytoplasma' species and alternative reference strains described are reported. For new 'Ca. Phytoplasma' species that will be assigned with identity ≥98.65 % of their 16S rRNA gene sequences, a threshold of 95 % genome-wide average nucleotide identity is suggested. When the whole genome sequences are unavailable, two among conserved housekeeping genes could be used. There are 49 officially published 'Candidatus Phytoplasma' species, including 'Ca. P. cocostanzaniae' and 'Ca. P. palmae' described in this manuscript.

Cation Permeability of Voltage-Gated Hair Cell Ca2+ Channels of the Vertebrate Labyrinth

Some hearing, vestibular, and vision disorders are imputable to voltage-gated Ca²⁺ channels of the sensory cells. These channels convey a large Ca²⁺ influx despite extracellular Na⁺ being 70-fold more concentrated than Ca²⁺; such high selectivity is lost in low Ca²⁺, and Na⁺ can permeate. Since the permeation properties and molecular identity of sensory Ca²⁺ channels are debated, in this paper, we examine the Na⁺ current flowing through the L- and R-type Ca²⁺ channels of labyrinth hair cells. Ion currents and cytosolic free Ca²⁺ concentrations were simultaneously monitored in whole-cell recording synchronous to fast fluorescence imaging. L-type and R-type channels were present with different densities at selected sites. In 10 nM Ca²⁺, the activation and deactivation time constants of the L-type Na⁺ current were accelerated and its maximal amplitude increased by 6-fold compared to physiological Ca²⁺. The deactivation of the R-type Na⁺ current was not accelerated, and its current amplitude increased by 2.3-fold in low Ca²⁺; moreover, it was partially blocked by nifedipine in a voltage- and time-dependent manner. In conclusion, L channel gating is affected by the ion species permeating the channel, and its selectivity filter binds Ca²⁺ more strongly than that of R channel; furthermore, external Ca²⁺ prevents nifedipine from perturbing the R selectivity filter.

The Virome of ‘Lamon Bean’: Application of MinION Sequencing to Investigate the Virus Population Associated with Symptomatic Beans in the Lamon Area, Italy

‘Lamon bean’ is a protected geographical indication (PGI) for a product of four varieties of bean (Phaseolus vulgaris L.) grown in a specific area of production, which is located in the Belluno district, Veneto region (N.E. of Italy). In the last decade, the ‘Lamon bean’ has been threatened by severe virus epidemics that have compromised its profitability. In this work, the full virome of seven bean samples showing different foliar symptoms was obtained by MinION sequencing. Evidence that emerged from sequencing was validated through RT-PCR and ELISA in a large number of plants, including different ecotypes of Lamon bean and wild herbaceous hosts that may represent a virus reservoir in the field. Results revealed the presence of bean common mosaic virus (BCMV), cucumber mosaic virus (CMV), peanut stunt virus (PSV), and bean yellow mosaic virus (BYMV), which often occurred as mixed infections. Moreover, both CMV and PSV were reported in association with strain-specific satellite RNAs (satRNAs). In conclusion, this work sheds light on the cause of the severe diseases affecting the ‘Lamon bean’ by exploitation of MinION sequencing.

Pathogenicity of Phytopythium chamaehyphon: A New Player in Kiwifruit Vine Decline Syndrome of Actinidia chinensis var. deliciosa 'Hayward' in Italy

Kiwifruit vine decline syndrome (KVDS) is a serious soil-borne disease that degrades the fine roots of both Actinidia chinensis var. deliciosa and var. chinensis. The disease seems to be the result of an interaction between several soil-borne pathogens, mostly oomycetes, and waterlogging. This work investigates the pathogenicity of the oomycete Phytopythium chamaehyphon recently isolated from roots of diseased plants. Pathogenicity was tested in 6-month-old and 1-year-old plants that, after inoculation, were flooded up to three times to induce symptom appearance. Leaf wilting and root rot typical of KVDS was observed in all the plants inoculated with P. chamaehyphon strain KD-15 (PCHA) and in all the positive controls potted in a mix of peat and soils collected in KVDS-affected orchards, while negative controls remained symptomless. Disease development on 6-month-old plants was characterized by unusual degradation of the not-lignified collar, occurring even in absence of flooding. Conversely, on 1-year-old plants, symptoms faithfully reproduced KVDS dynamics observed in orchard. This work confirmed the pathogenicity of P. chamaehyphon and raised new questions about the actual role of waterlogging in KVDS etiology.