ATP synthase catalyzes the synthesis of ATP by consuming the proton electrochemical gradient, which is essential for maintaining the life activity of organisms. The peripheral stalk belongs to ATP ...synthase and plays an important supporting role in the structure of ATP synthase, but their regulation in filamentous fungi are not yet known. Here, we characterized the subunits of the peripheral stalk, FfATPh, FfATP5, and FfATPb, and explored their functions on development and pathogenicity of Fusarium Fujikuroi. The FfATPh, FfATP5, and FfATPb deletion mutations (∆FfATPh, ∆FfATP5, and ∆FfATPb) presented deficiencies in vegetative growth, sporulation, and pathogenicity. The sensitivity of ∆FfATPh, ∆FfATP5, and ∆FfATPb to fludioxonil, phenamacril, pyraclostrobine, and fluazinam decreased. In addition, ∆FfATPh exhibited decreased sensitivity to ionic stress and osmotic stress, and ∆FfATPb and ∆FfATP5 were more sensitive to oxidative stress. FfATPh, FfATP5, and FfATPb were located on the mitochondria, and ∆FfATPh, ∆FfATPb, and ∆FfATP5 disrupted mitochondrial location. Furthermore, we demonstrated the interaction among FfATPh, FfATP5, and FfATPb by Bimolecular Fluorescent Complimentary (BiFC) analysis. In conclusion, FfATPh, FfATP5, and FfATPb participated in regulating development, pathogenicity, and sensitivity to fungicides and stress factors in F. fujikuroi.
The excessive use of fungicides against Venturia inaequalis, the causal agent of apple scab, has led to the emergence of resistant populations to multiple fungicides over the years. In Greece, there ...is no available information on fungicide resistance, despite the fact that control failures have been reported on certain areas. An amount of 418 single-spore isolates were collected from three major apple production areas and tested for their sensitivity to eight commonly used fungicides from unrelated chemical groups. The isolates were tested on malt extract agar media enriched with the discriminatory dose of each fungicide using the point inoculation method. To define the discriminatory dose for assessing the levels of resistance, ECsub.50 values on both spore germination and mycelial growth assays were previously determined. Isolates exhibiting high resistance to trifloxystrobin (92% in total) and difenoconazole (3%); and moderate resistance to cyprodinil (75%), dodine (28%), difenoconazole (36%), boscalid (5%), and fludioxonil (7%) were found for the first time in Greece. A small percentage of the isolates were also found less sensitive to captan (8%) and dithianon (6%). Two isolates showed various levels of resistance to all eight fungicides. Despite the occurrence of strains with multiple resistances to many fungicides, we concluded that this practical resistance in the field arose mainly due to the poor control of apple scab with trifloxystrobin and difenoconazole.
BACKGROUND An increasing number of publications have claimed that demethylation inhibitor (DMI) fungicides are confronted with resistance development in the fungus Aspergillusfumigatus and that the ...origin of resistant isolates may also be outside the medical area. For resistance risk assessment and sourcing the origin of DMI resistance, the primary exposure events of A.fumigatus with DMI treatments have been analysed case by case, resulting in the pathogen exposure risk (PER). RESULTS The calculated maximum exposure concentrations (MEC) are highest during medical treatments (human and veterinary), certain fruit and seed treatments and wood preservation, and are much lower for crop protection applications. Most agricultural DMIs are intrinsically10-100 times less active than medical DMIs for A.fumigatus control and potential resistance selection. However, imazalil is used in agriculture and veterinary medicine (as enilconazole) expressing strong intrinsic activity against A.fumigatus . The majority of mutations in the target gene, cyp51 , of DMI-resistant isolates are different in A.fumigatus (e.g. TR sub(34)/L98H) in comparison with plant pathogens (e.g. A379G, I381V). CONCLUSIONS The assumed selection risk, ASR (MECPER) for resistance evolution to DMIs in A.fumigatus is estimated to be highest for human and veterinary applications. However, environmental origin of DMI-resistant spores from certain sites cannot be ruled out. copyright 2013 Society of Chemical Industry
Azole fungicides are widely used to treat fungal infection in human. After application, these chemicals may reach to the receiving environment via direct or indirect discharge of wastewaters, thus ...posing potential risks to non-target organisms. We aimed to review the occurrence, fate and toxicological effects of some representative household azole fungicides in the environment. Azole fungicides were widely detected in surface water and sediment of the aquatic environment due to their incomplete removal in wastewater treatment plants. These chemicals are found resistant to microbial degradation, but can undergo photolysis under UV irradiation. Due to different physiochemical properties, azole fungicides showed different environmental behaviors. The residues of azole fungicides could cause toxic effects on aquatic organisms such as algae and fish. The reported effects include regulation changes in expression of cytochrome P450-related genes and alteration in CYP450-regulated steroidogenesis causing endocrine disruption in fish. Further studies are essential to investigate the removal of azole fungicides by advanced treatment technologies, environmental fate such as natural photolysis, and toxic pathways in aquatic organisms.
•Azole fungicides are widely detected in various environmental compartments.•Resistance to biodegradation and absorption into sludge result in their ubiquity.•High toxic risks to algae, shrimp and frog are expected at effluent discharge points.•Disturbance in CYP450-mediated metabolism and steroidogenesis has been shown.•Further research on engineered and natural removals and toxic pathways is needed.
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