Attributes of Cyazofamid-Resistant Phytophthora litchii Mutants and Its Impact on Quality of Litchi Fruits.

In this study, we determined the sensitivity of 148 Phytophthora litchii isolates to cyazofamid, yielding a mean EC50 value of 0.0091 ± 0.0028 µg/mL. Through fungicide adaptation, resistant mutants (RMs) carrying the F220L substitution in PlCyt b were derived from wild-type isolates. Notably, these RMs exhibited a lower fitness compared with the parental isolates. Molecular docking analysis further revealed that the F220L change contributed to a decrease in the binding energy between cyazofamid and PlCyt b. The total phenol and flavonoid contents in the litchi pericarp treated with cyazofamid on day 5 were significantly higher than in other treatments. Overall, the laboratory assessment indicated a moderate risk of cyazofamid resistance in P. litchii, but the emergence of the F220L change could lead to a high level of resistance. Thus, cyazofamid represents a promising agrochemical for controlling postharvest litchi downy blight and extending the shelf life of litchi fruits.

Resistance risk and resistance-related point mutations in cytochrome b of florylpicoxamid in Colletotrichum scovillei.

Anthracnose caused by Colletotrichum scovillei is one of the most destructive diseases of chili worldwide. Florylpicoxamid is a new quinone inside inhibitor (QiI) fungicide, which shows intensively inhibitory activity against C. scovillei. Currently, florylpicoxamid is in the registration process to control chili anthracnose in China. This study investigated the risk of resistance and resistance genetic mechanism of C. scovillei to florylpicoxamid. Baseline sensitivity of 141C. scovillei isolates to florylpicoxamid was established with an average EC50 value of 0.2328 ± 0.0876 µg/mL. A total of seven stable florylpicoxamid-resistant mutants were obtained with resistance factors ranging from 41 to 276. The mutants showed similar or weaker traits in mycelial growth, sporulation, conidial germination and pathogenicity than their parental isolates. Generally, the resistance risk of C. scovillei to florylpicoxamid would be moderate. In addition, there was no cross-resistance between florylpicoxamid and the commercially available fungicides tested. A37V and S207L mutations in the cytochrome b protein were detected in four high-resistance and three moderate-resistance mutants, respectively, of which, S207L is a new mutation. Molecular docking showed that the two mutations conferred different resistance levels to florylpicoxamid. These results provide a new perspective for QiI fungicide-resistance mechanism and may help in the reasonable use of florylpicoxamid against chili anthracnose in the future.

Influence of Psychological Factors in Primary Dysmenorrhea Patients on De qi: a Secondary Analysis of a Randomized Controlled Trial.

Background: De qi , the needling sensation, is important in acupuncture treatment. Almost all studies believe that deep needling and manipulation could achieve a significant de qi sensation. However, relatively few studies have examined the effect of psychological factors on de qi, and those that did often reached different conclusions. Objectives: To explore the influence of psychologic factors on de qi in patients with primary dysmenorrhea (PD). Methods: Sixty-eight PD patients with cold and dampness stagnation were randomly allocated to de qi (deep insertion using thick needles, with manipulation, n=17) and non-de qi groups (shallow insertion using thin needles, without manipulation, n=51). Both groups received bilateral needling at Sanyinjiao (SP6) for 30 min. De qi was assessed using the Acupuncture De qi Clinical Assessment Scale (ADCAS). The patients' acupuncture-related anxiety and their expectations of the relationship between needle sensation and curative effect were evaluated using a five-point and four-point scale, respectively. Results: Within the de qi group, all patients experienced the de qi sensation, although anxiety levels were unrelated to de qi. Patients' expectations correlated negatively with de qi timing, and positively with electric sensation. Within the non-de qi group, 59.5% of patients experienced de qi. Between those who experienced it and those who did not, no significant differences were found in anxiety levels, although patients' expectations differed significantly. Among patients who experienced de qi sensations in the non-de qi group, anxiety and throbbing were positively correlated. Additionally, patients' expectations correlated positively with de qi intensity, as well as coldness, and numbness. Conclusion: Psychological factors should be considered when studying de qi since PD patients' expectations could influence the de qi sensation at SP6.

Evaluation of Amisulbrom Products for the Management of Clubroot of Canola (Brassica napus).

Clubroot, caused by Plasmodiophora brassicae, is an important disease of canola (Brassica napus). Amisulbrom, a quinone inside inhibitor (QiI), was evaluated for its effectiveness in clubroot management in Alberta, Canada. Resting spores of P. brassicae were treated in vitro with 0, 0.01, 0.1, 1, and 10% (w/v) amisulbrom to determine its effect on spore germination and viability. Amisulbrom inhibited resting spore germination by up to 79% and reduced viable spores by 31% relative to the control. Applications of a liquid solution (AL1000, 1000 g active ingredient (ai) ha-1) and granular formulations (AF700, 700 g ai ha-1; AF1000, 1000 g ai ha-1; AF1500, 1500 g ai ha-1) of amisulbrom were tested on the canola cultivars '45H31' (clubroot-susceptible) and 'CS2000' (moderately resistant) under greenhouse conditions and in field experiments in 2019 and 2020. In the greenhouse, the treatments were evaluated at inoculum concentrations of 1 × 105 or 1 × 107 resting spores g-1 soil. A trend of decreasing clubroot severity with an increasing amisulbrom rate was observed. At the lower spore concentration, treatment with AF1500 resulted in a clubroot disease severity index (DSI) <20% for both cultivars, while the lowest DSI under both low and high spore concentrations was obtained with AL1000. The field results indicated a significant reduction in DSI, with varied effects of rates and liquid vs. granular formulations. The greatest reductions (up to 58.3%) in DSI were obtained with AF1500 and AL1000 in 2020. These findings suggest that amisulbrom holds promise as part of an integrated clubroot management approach.

Baseline sensitivity of European Zymoseptoria tritici populations to the complex III respiration inhibitor fenpicoxamid.

BACKGROUND: Fenpicoxamid is a recently developed fungicide belonging to the quinone inside inhibitor (QiI) group. This is the first fungicide within this group to be active against the Zymoseptoria tritici, which causes Septoria tritici blotch on wheat. The occurrence of pre-existing resistance mechanisms was monitored, using sensitivity assays and Illumina sequencing, in Z. tritici populations sampled in multiple European countries before the introduction of fenpicoxamid. RESULTS: Although differences in sensitivity to all three fungicides tested (fenpicoxamid, fentin chloride and pyraclostrobin) existed between the isolate collections, no alterations associated with QiI resistance were detected. Among the isolates, a range in sensitivity to fenpicoxamid was observed (ratio between most sensitive/least sensitive = 53.1), with differences between the most extreme isolates when tested in planta following limited fenpicoxamid treatment. Sensitivity assays using fentin chloride suggest some of the observed differences in fenpicoxamid sensitivity are associated with multi-drug resistance. Detailed monitoring of the wider European population using Illumina-based partial sequencing of the Z. tritici also only detected the presence of G143A, with differences in frequencies of this alteration observed across the region. CONCLUSIONS: This study provides a baseline sensitivity for European Z. tritici populations to fenpicoxamid. Target-site resistance appears to be limited or non-existing in European Z. tritici populations prior to the introduction of fenpicoxamid. Non-target site resistance mechanisms exist, but their impact in the field is predicted to be limited. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Fungicide sensitivity levels in the Lithuanian Zymoseptoria tritici population in 2021.

Zymoseptoria tritici causes the disease known as septoria leaf blotch in winter wheat and is a major factor in yield loss worldwide. Farmers are inclined to use fungicides to protect their crops; however, the efficacy of these measures is rapidly decreasing due to the natural mechanisms of mutation emergence in pathogen populations. Increasing fungicide resistance is being recorded worldwide, therefore, screening of the current situation in Lithuania is essential to determine the subsequent steps of crop protection strategies. In this study, in vitro fungicide sensitivity tests, mutation detection, and field experiments were carried out. The mean EC50 values for prothioconazole-desthio and mefentrifluconazole were 0.14 and 0.28 mg/l, respectively. Increased frequency of the mutation S524T, linked to DMIs resistance, was observed. Results revealed that the dominant point mutation in the gene CYP51 was I381V, and the most frequent CYP51 haplotype was D13 (V136C, I381V, Y461H, S524T). The mutation G143A, linked to QoI resistance, was detected in ¾ of the population. Mutations conferring resistance to SDHIs were not detected in single pycnidium isolates. Two-year field experiments likewise showed no decline in field efficacy of SDHI fungicide in Lithuania. Moreover, the baseline sensitivity of the Lithuanian Z. tritici population to QiI fungicide fenpicoxamid was established. The findings of this study provide an update on the current status of fungicide resistance in the Lithuanian Z. tritici population.

Chemical analysis of callus extracts from toxic and non-toxic varieties of Jatropha curcas L.

Jatropha curcas L. belongs to Euphorbiaceae family, and it synthesizes flavonoid and diterpene compounds that have showed antioxidant, anti-inflammatory, anticancer, antiviral, antimicrobial, antifungal and insecticide activity. Seeds of this plant accumulate phorbol esters, which are tigliane type diterpenes, reported as toxic and, depending on its concentration, toxic and non-toxic varieties has been identified. The aim of this work was to characterize the chemical profile of the extracts from seeds, leaves and callus of both varieties (toxic and non-toxic) of Jatropha curcas, to verify the presence of important compounds in dedifferentiated cells and consider the possibility of using these cultures for the massive production of metabolites. Callus induction was obtained using NAA (1.5 mg L-1) and BAP (1.5 mg L-1) after 21 d for both varieties. Thin layer chromatography analysis showed differences in compounds accumulation in callus from non-toxic variety throughout the time of culture, diterpenes showed an increase along the time, in contrast with flavonoids which decreased. Based on the results obtained through microQTOF-QII spectrometer it is suggested a higher accumulation of phorbol esters, derived from 12-deoxy-16-hydroxy-phorbol (m/z 365 [M+H]+), in callus of 38 d than those of 14 d culture, from both varieties. Unlike flavonoids accumulation, the MS chromatograms analysis allowed to suggest lower accumulation of flavonoids as the culture time progresses, in callus from both varieties. The presence of six glycosylated flavonoids is also suggested in leaf and callus extracts derived from both varieties (toxic and non-toxic), including: apigenin 6-C-α-L-arabinopyranosyl-8-C-ß -D-xylopyranoside (m/z 535 [M+H]+), apigenin 4'-O-rhamnoside (m/z 417 [M+H]+), vitexin (m/z 433 [M+H]+), vitexin 4'-O-glucoside-2″-O-rhamnoside (m/z 741 [M+H]+), vicenin-2 (m/z 595 [M+H]+), and vicenin-2,6″-O-glucoside (m/z 757 [M+H]+).

The cytochrome bc1 complex as an antipathogenic target.

The cytochrome bc1 complex is a key component of the mitochondrial respiratory chains of many eukaryotic microorganisms that are pathogenic for plants or humans, such as fungi responsible for crop diseases and Plasmodium falciparum, which causes human malaria. Cytochrome bc1 is an enzyme that contains two (ubi)quinone/quinol-binding sites, which can be exploited for the development of fungicidal and chemotherapeutic agents. Here, we review recent progress in determination of the structure and mechanism of action of cytochrome bc1 , and the associated development of antimicrobial agents (and associated resistance mechanisms) targeting its activity.

Mitochondrial complex III Qi -site inhibitor resistance mutations found in laboratory selected mutants and field isolates.

BACKGROUND: Complex III inhibitors targeting the Qi -site have been known for decades; some are used or being developed as antimicrobial compounds. Target site resistance mutations have been reported in laboratory-selected mutants and in field isolates. Here, we present a brief overview of mutations found in laboratory-selected resistant mutants. We also provide a study of mutations observed in field isolates of Plasmopara viticola, in particular the ametoctradin resistance substitution, S34L that we analysed in the yeast model. RESULTS: A survey of laboratory mutants showed that resistance could be caused by a large number of substitutions in the Qi -site. Four residues seemed key in term of resistance: N31, G37, L198 and K228. Using yeast, we analysed the effect of the ametoctradin resistance substitution S34L reported in field isolates of P. viticola. We showed that S34L caused a high level of resistance combined with a loss of complex III activity and growth competence. CONCLUSION: Use of single site Qi -site inhibitors is expected to result in the selection of resistant mutants. However, if the substitution is associated with a fitness penalty, as may be the case with S34L, resistance development might not be an insuperable obstacle, although careful monitoring is required. © 2018 Society of Chemical Industry.

Quality Initiative in Clinical Practice: A Single-Institution Appraisal of Quality Metrics in the Management of Newly Diagnosed Diffuse Large B-Cell Lymphoma.

OBJECTIVE: To assess our adherence to treatment guidelines for diffuse large B-cell lymphoma (DLBCL) established by the American Society of Hematology in 2014 through implementation of a quality improvement initiative (QII) at our institution in 2015. PATIENTS AND METHODS: Patients with newly diagnosed DLBCL treated from January 1, 2006, through December 31, 2017, were identified. Electronic medical records were reviewed for documentation of American Society of Hematology Practice Improvement Module quality measures (eg, key pathologic features of DLBCL, lymphoma staging, and screening for hepatitis B virus [HBV] infection in patients receiving rituximab-based chemotherapy). We also reviewed assessment of prognosis by revised International Prognostic Index score, testing for hepatitis C virus, HBV, and HIV, chemotherapy education, and the addition of rituximab in the treatment regimen of CD20+ DLBCL. RESULTS: Following QII implementation, we saw improvements in most metrics, including reporting of key molecular features (fluorescence in situ hybridization for c-MYC, BCL2, and BCL6, from 45.5% [75 of 165 patients] before QII to 91.7% [22 of 24 patients] after QII; P<.001), screening for HBV (41.8% [69 of 165 patients] to 91.7% [22 of 24 patients]; P<.001) and HIV infections (33.9% [56 of 165 patients] to 87.5% [21 of 24 patients]; P<.0001), providing chemotherapy education (92.7% [153 of 165 patients] to 100%), and use of rituximab for CD20+ DLBCL (83.6% [138 of 165 patients] to 100%; P=.05). All patients had positron emission tomography-computed tomography for DLBCL staging, and there was significantly lower use of bone marrow biopsy (P=.011). CONCLUSION: Implementating a QII and employing standardized metrics can aid in improving quality of care for patients with newly diagnosed DLBCL and allow opportunities to build and ensure better adherence to evolving patient care guidelines.