To see the other types of publications on this topic, follow the link: Fungicides.
Journal articles on the topic 'Fungicides'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Fungicides.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Tompros, Adrianna, Mark Q. Wilber, Andy Fenton, Edward Davis Carter, and Matthew J. Gray. "Efficacy of Plant-Derived Fungicides at Inhibiting Batrachochytrium salamandrivorans Growth." Journal of Fungi 8, no. 10 (September 28, 2022): 1025. http://dx.doi.org/10.3390/jof8101025.
Full textAbstract:
The emerging fungal amphibian pathogen, Batrachochytrium salamandrivorans (Bsal), is currently spreading across Europe and given its estimated invasion potential, has the capacity to decimate salamander populations worldwide. Fungicides are a promising in situ management strategy for Bsal due to their ability to treat the environment and infected individuals. However, antifungal drugs or pesticides could adversely affect the environment and non-target hosts, thus identifying safe, effective candidate fungicides for in situ treatment is needed. Here, we estimated the inhibitory fungicidal efficacy of five plant-derived fungicides (thymol, curcumin, allicin, 6-gingerol, and Pond Pimafix®) and one chemical fungicide (Virkon® Aquatic) against Bsal zoospores in vitro. We used a broth microdilution method in 48-well plates to test the efficacy of six concentrations per fungicide on Bsal zoospore viability. Following plate incubation, we performed cell viability assays and agar plate growth trials to estimate the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of each fungicide. All six fungicides exhibited inhibitory and fungicidal effects against Bsal growth, with estimated MIC concentrations ranging from 60 to 0.156 μg/mL for the different compounds. Allicin showed the greatest efficacy (i.e., lowest MIC and MFC) against Bsal zoospores followed by curcumin, Pond Pimafix®, thymol, 6-gingerol, and Virkon® Aquatic, respectively. Our results provide evidence that plant-derived fungicides are effective at inhibiting and killing Bsal zoospores in vitro and may be useful for in situ treatment. Additional studies are needed to estimate the efficacy of these fungicides at inactivating Bsal in the environment and treating Bsal-infected amphibians.
2
O'Brien, RG, LL Vawdrey, and RJ Glass. "Fungicide resistance in cucurbit powdery mildew (Sphaerotheca fuliginea) and its effect on field control." Australian Journal of Experimental Agriculture 28, no. 3 (1988): 417. http://dx.doi.org/10.1071/ea9880417.
Full textAbstract:
Decreased fungicidal control of powdery mildew (Sphaerotheca fuliginea (Schlecht: Fr.) Poll.) in commercial cucurbit crops led to an investigation to determine whether fungicide resistant strains were present. In field trials, fungicides such as bupirimate (100 mg a.i. L-I), dimethirimol (250 mg a.i. L-1), fenarimol (36 mg a.i. L-1), penconazole (40 mg a.i. L-l) and triadimefon (125 mg a.i. L-1) were less effective (P=0.01) in controlling the disease than oxythioquinox (100 mg a.i. L-1). This disagreed with earlier trial results and suggested that fungicide resistant strains may have developed. The sensitiyities of 6 isolates of S. fuliginea to 12 fungicides were determined using a leaf disc technique. Two isolates collected in fields where fungicides had been used intensively showed reduced sensitivity to fungicides from several chemical groups including the ergosterol biosynthesis inhibitors, hydroxypyrimidines, organophosphates and benzimidazoles. Several spraying strategies were compared. The S. fuliginea populations receiving spray schedules which included the protectant fungicide oxythioquinox alone, or in alternation with a systemic (triadimefon) developed a lower proportion (66-73%) of resistant strains than those treated with systemic fungicide alone (89%). These findings suggest that S. fuliginea can develop strains with low sensitivity to several fungicides against powdery mildew. To prolong their efficacy, systemic fungicides should not be used continuously but should be reserved for use during the latter part of crop growth when disease risk is highest. Alternating or tank mixing with an effective protectant fungicide is also recommended.
3
RANI, RITU, VINEET K. SHARMA, PARDEEP KUMAR, and C. MOHAN. "Impact of simulated rainfall on persistence of fungicides used against late blight (Phytophthora infestans) of tomato (Solanum lycopersicum)." Indian Journal of Agricultural Sciences 85, no. 2 (February 12, 2015): 256–60. http://dx.doi.org/10.56093/ijas.v85i2.46532.
Full textAbstract:
Persistence of mancozeb 75%WP and metalaxyl 8%+mancozeb 64 %WP fungicides was studied on tomato (Solanum lycopersicum L.) leaves with respect to different simulated rain amounts (0, 5, 10 and 15mm) after different number of days (0, 2, 4, 6, 8 and 10) after fungicidal spray. Rainfall applied immediately after fungicidal spray removed fungicides from the leaf surface resulting in higher disease severity. As rain amount increased from 5 to 15 mm, disease was also increased in both the test fungicides. In case of metalaxyl 8%+mancozeb 64 %WP @ 0.25 per cent, disease severity was less as compared to the mancozeb 75%WP @ 0.25 per cent. The delaying of rainfall by 2 days after fungicidal spray resulted in significant reduction in disease severity in case of metalaxyl 8%+mancozeb 64%WP sprayed tomato plants. Metalaxyl 8%+mancozeb 64%WP being a systemic fungicide was absorbed into the system of the plant. However, this was not true in case of mancozeb 75%WP sprayed tomato plants. Since, mancozeb 75 %WP a non systemic fungicide was washed with the application of rain.
4
Ngibad, Khoirul, Afidatul Muadifah, Lailatul Jannah Triarini, Laily Rizki Amalia, and Novita Karel Damayanti. "A review of application of natural products as fungicides for chili." Environmental and Toxicology Management 1, no. 2 (May 22, 2021): 9–22. http://dx.doi.org/10.33086/etm.v1i2.2022.
Full textAbstract:
Anthracnose disease in chillies is a serious problem for farmers. So far, synthetic fungicides have been used as solution for the treatment of this disease. However, the side effects of synthetic fungicides to public health and environment raised awareness on alternative fungicides derived from natural resources. This paper aims to review plants that are potential as an alternative to fungicides for chili plantation, fabrication of test solutions, in vitro and in vivo fungicide test. Many plants were investigated as alternatives to plant-based fungicide. The utilization of leaves as samples including rhizomes, roots, tubers, weevils, seeds, fruit, flowers and other parts of the plant. The extract fabrication method used as a fungicide test include: maceration method, gradual fractionation method, and decoction method. The maceration method is the method most widely used to extract fungicidal active compounds from plants. Some studies that carried out in vitro tests were unable to compare with synthetic fungicides so it was not possible to determine their effectiveness for plant-based fungicide for chillies when compared to synthetic fungicides. In vitro Extract of 80% alcohol and 10%/60% n-hexane of pacar cina (Aglaia odorata L.) leaves can be compared with the performance of propineb 0.2%. In addition, the 60% and 70% kirinyuh (Chromolaena odorata L.) leaf extracts were also able to match Acrobat 0.2% performance in vitro. Based on the in vivo test, suren (Toona sureni Merr) leaf extract and nut bulbs can be used as an alternative to vegetable / natural fungicides to help overcome the problem of anthracnose in chilies.
5
Tarnowski, T. L. B., A. T. Savelle, and H. Scherm. "Activity of Fungicides Against Monilinia vaccinii-corymbosi in Blueberry Flowers Treated at Different Phenological Stages." Plant Disease 92, no. 6 (June 2008): 961–65. http://dx.doi.org/10.1094/pdis-92-6-0961.
Full textAbstract:
The activity of fenbuconazole and azoxystrobin applied to blueberry flowers at different phenological stages against subsequent gynoecial infection by the mummy berry fungus Monilinia vaccinii-corymbosi was evaluated. In the greenhouse, potted blueberry plants having flower clusters at five distinct stages (from bud scale separation to anthesis) were treated with the two fungicides. One day after anthesis (between 1 and 15 days after fungicide treatment), individual flowers were detached and inoculated with conidia of M. vaccinii-corymbosi in the laboratory. Four days after inoculation, hyphal ingress into the style was determined microscopically as a measure of fungicide efficacy. Results revealed a significant flower stage effect (P < 0.0001), whereby only fungicide application at anthesis but not at the four preanthesis stages reduced subsequent fungal ingress into the style. There was no significant difference between the two fungicides (P > 0.50) nor was there a significant fungicide–flower stage interaction (P > 0.30). In the field during 2 years, mature blueberry plants were treated with the two fungicides and exposed to natural pathogen inoculum. At the time of application, flower clusters at anthesis and at three preanthesis stages were selected and tagged. Mummy berry incidence in fruit developing from the tagged clusters was assessed to determine treatment effects. Whereas fenbuconazole lowered disease incidence for all preanthesis stages, azoxystrobin was effective only at the latest preanthesis stage. The discrepancy between these results and those of the greenhouse study (where there was no preanthesis activity of either fungicide) indirectly suggests post-infection fungicidal activity in the ovary, the base of which was exposed to the fungicide spray at the time of treatment for all flower phenology stages. Thus, although there appears to be insufficient translocation of the two fungicides in flowers treated at preanthesis stages to prevent stylar ingress by the pathogen, fungicidal activity in the ovary may be sufficient to halt subsequent fungal colonization, especially for fenbuconazole. To prescribe the most effective management program for flower-infecting fungi, translocation and post-infection activity of fungicides in floral tissues must be better understood.
6
N. Srinivasan and M. Gunasekaran. "FIELD CONTROL OF LEAF ROT DISEASE OF COCONUT WITH FUNGICIDES." CORD 12, no. 02 (December 1, 1996): 34. http://dx.doi.org/10.37833/cord.v12i02.303.
Full textAbstract:
Leaf rot is a disease of fungal complex super imposed on root (wilt) affected coconut palms in India. A field fungicidal control trial on the disease involving contact (indofil M‑45, Fytolan) and systemic (Calixin) fungicides was conducted Fungicidal treatments, spraying of Indofil M‑45 and pouring of Calixin into axil of spindle, were found beneficial as the disease intensity reduced in newly emerged leaves. However, the extent of disease amelioration by fungicides was marginal to moderate level only. Importance of broad spectrum fungicide(s) and measures of disease protection are outlined.
7
Da Silveira, Amanda Letícia, Maria Gilmara Oliveira Soares, Sarah Da Silva Costa Guimarães, Fernanda Dias Pereira, Bruna Canabarro Pozzebon, and Eduardo Alves. "AVALIAÇÃO DA SENSIBILIDADE in vitro DE ISOLADOS DE Colletotrichum spp. À FUNGICIDAS." Nativa 8, no. 1 (February 5, 2020): 01. http://dx.doi.org/10.31413/nativa.v8i1.7443.
Full textAbstract:
Doenças pós-colheita estão entre os principais fatores que reduzem a produção da bananeira. Dentre elas a antracnose se destaca. Causada pelo fungo Colletotrichum spp. essa doença interfere na qualidade dos frutos reduzindo seu tempo de prateleira. Como medida de controle a utilização de produtos químicos tem sido a mais utilizada e com isso tem se observado a ineficiência de alguns princípios ativos. Dessa forma, o objetivo desse trabalho foi avaliar a sensibilidade micelial in vitro de isolados de Colletotrichum spp., submetidos a diferentes doses de fungicidas. O delineamento experimental foi inteiramente ao acaso com 5 isolados, 3 fungicidas, 4 doses (0,1; 1,0; 10; 100 mg L-1) e 3 repetições de cada tratamento. Discos de micélio de cada isolado foram adicionados em placas com as doses de cada fungicida. O crescimento micelial foi medido após o micélio dos fungos das placas controle atingirem suas bordas. Foi estimada a concentração efetiva dos fungicidas capaz de inibir em 50 % do crescimento micelial (EC50) e classificados em quatro categorias de eficiência. As análises estatísticas foram processadas com o programa SISVAR. Todos os fungicidas foram eficientes no controle in vitro, com destaque para o microbiológico. Para os isolados testados não foi observado resistência a nenhum dos fungicidas.Palavras-chave: pós-colheita; Bacillus subtillis; controle químico; antracnose. EVALUATION OF IN VITROUS SENSITIVITY OF ISOLATES OF Colletotrichum spp. TO FUNGICIDES ABSTRACT: Post-harvest diseases are among the main factors that reduce banana production. Among them the anthracnose stands out. Caused by the fungus Colletotrichum spp. this disease interferes in the quality of the fruits reducing their shelf life. As a control measure the use of chemicals has been the most used and with this has been observed the inefficiency of some active principles. Thus, the objective of this work was to evaluate the in vitro mycelial sensitivity of Colletotrichum spp. Isolates submitted to different doses of fungicides. The experimental design was completely randomized with 5 isolates, 3 fungicides, 4 doses (0.1, 1.0, 10, 100 mg L-1) and 3 replicates. Mycelial disks from each isolate were added on plates with the doses of each fungicide. Mycelial growth was measured after the fungal mycelium of the control plates reached their edges. The effective concentration of fungicides capable of inhibiting 50% of mycelial growth (EC 50) and classified into four efficiency categories was estimated. Statistical analyzes were processed using the SISVAR program. All the fungicides were efficient in the in vitro control, with emphasis on the microbiological. No resistance to any of the fungicides was observed for the isolates tested.Keywords: post-harvest; Bacillus subtillis; chemical control; anthracnose.
8
Sonah, Humira, Rupesh K. Deshmukh, and Anil S. Kotasthane. "Fungicidal Interference during Infection Related Developmental Stages in Magnaporthe grisea." International Journal of Phytopathology 1, no. 1 (December 15, 2012): 49–55. http://dx.doi.org/10.33687/phytopath.001.01.0015.
Full textAbstract:
Rice blast, a serious epidemic disease that limits grain yield worldwide is caused by fungal pathogen Magnaporthe grisea. The present investigation was carried out to identify the probable avenues of interference by different fungicides during the critical stages of infection related morphogenesis of M. grisea. Effect of six fungicides at different stages of infection related morphogenesis showed variable results like interference in conidial germination, distortion of surface structure of the spores, interference in the germ tube elongation, interference in the transfer of the cell contents from spore to appresorrium, deformity in appressorial dome, interference in the melanin deposition. We speculate the critical stages at which these fungicides may interfere. The activity of immunosuppressive drug cyclosporin A (CsA) which is a potential antifungal agent was equated with all the fungicides used. We hypothesize that the exposure of the M. grisea spore to the fungicide may lead to the formation of a cyclophilin CYP1-fungicide complex, which inactivates calcineurin and prevents calcium/ calmodulin-dependent protein phosphatase signaling and is therefore one of the target of fungicidal interference. An understanding of how fungal pathogens break the protective barrier that comprise the surface of the host plant as well as precise identification of avenues of fungicidal interference during infection related development in M. grisea will lead to novel approach for controlling plant diseases.
9
Jana, Poslušná, Plachká Eva, and Mazáková Jana. "Influence of selected fungicides registered in the Czech Republic for winter oilseed rape on in vitro Sclerotinia sclerotiorum mycelial growth." Plant Protection Science 54, No. 2 (February 10, 2018): 101–10. http://dx.doi.org/10.17221/137/2016-pps.
Full textAbstract:
The baseline sensitivity of 55 isolates of Sclerotinia sclerotiorum, collected from oilseed rape in 6 regions of the Czech Republic, to selected fungicides was determined during the period 2013–2015. One single-component fungicide – Horizon (tebuconazole), and four multicomponent fungicides – Pictor (boscalid, dimoxystrobin), Efilor (boscalid, metconazole), Prosaro 250 EC (prothioconazole, tebuconazole), and Propulse (fluopyram, prothioconazole), were chosen as these are commonly used locally. The effect of each fungicide on the in vitro pathogen radial mycelial growth and EC<sub>50 </sub>values for the respective fungicides were determined. The following MIC values were estimated; for the fungicides Horizon 250 EW, Efilor, and Propulse the mean MIC values ranged between 0.125 and 0.250 µl/ml, for Prosaro 250 EC ranged between 0.0625 and 0.125 µl/ml, and for Pictor ranged from 0.00781 to 0.01562 µl/ml. No strains of S. sclerotiorum resistant to the tested fungicides were detected and the growth of all isolates was fully inhibited at concentrations corresponding to their registered dose rates. The highest fungicidal efficacy on the collected S. sclerotiorum isolates was recorded for Pictor, followed by Prosaro 250 with an EC<sub>50</sub> value 0.05856 µl/ml and then the remaining fungicides Propulse, Efilor, and Horizon 250 EW (EC<sub>50</sub> values 0.07277, 0.07221, and 0.08519 µl/ml, respectively).
10
Yellareddygari, S. K. R., Raymond J. Taylor, Julie S. Pasche, and Neil C. Gudmestad. "Quantifying Control Efficacy of Fungicides Commonly Applied for Potato Early Blight Management." Plant Disease 103, no. 11 (November 2019): 2821–24. http://dx.doi.org/10.1094/pdis-03-19-0670-re.
Full textAbstract:
Early blight is an economically important foliar disease of potato in the United States. Because of the lack of resistant potato cultivars, fungicides are applied extensively to obtain adequate control. To manage early blight, standard protectant fungicides and single-site mode-of-action “specialty” fungicides are applied either alone or incorporated into a fungicide rotation program. Control efficacy at two crop growth stages (tuber initiation/early bulking and late bulking/tuber maturation) and the overall tuber yield response to standard and specialty fungicides were assessed using network metaanalytic models. Control efficacy of fungicides ranged from moderate to very high (>30 to 75%) compared with the nontreated control. For both potato growth stages, specialty fungicides performed better than standard protectant fungicides. Furthermore, control efficacy of both fungicides was higher (3 to 9%) at late bulking and tuber maturation when compared with early bulking crop growth stage. Specialty fungicide programs increased overall tuber yields by 4 and 9% over standard fungicides and nontreated control, respectively. Based on the results, more precise fungicide use recommendations and fungicide programs can be developed for early blight management.
11
Bandara, Ananda Y., Dilooshi K. Weerasooriya, Shawn P. Conley, Tom W. Allen, and Paul D. Esker. "Modeling the relationship between estimated fungicide use and disease-associated yield losses of soybean in the United States II: Seed-applied fungicides vs seedling diseases." PLOS ONE 15, no. 12 (December 28, 2020): e0244424. http://dx.doi.org/10.1371/journal.pone.0244424.
Full textAbstract:
Use of seed-applied fungicides has become commonplace in the United States soybean production systems. Although fungicides have the potential to protect seed/seedlings from critical early stage diseases such as damping-off and root/stem rots, results from previous studies are not consistent in terms of seed-applied fungicide’s ability to mitigate yield losses. In the current study, the relationship between estimated soybean production losses due to seedling diseases and estimated seed-applied fungicide use was investigated using annual data from 28 soybean growing states in the U.S. over the period of 2006 to 2014. National, regional (northern and southern U.S.), state, and temporal scale trends were explored using mixed effects version of the regression analysis. Mixed modeling allowed computing generalized R2 values for conditional (R2GLMM(c); contains fixed and random effects) and marginal (R2GLMM(m); contains only fixed effects) models. Similar analyses were conducted to investigate how soybean production was related to fungicide use. National and regional scale modeling revealed that R2GLMM(c) values were significantly larger compared to R2GLMM(m) values, meaning fungicide use had limited utility in explaining the national/regional scale variation of yield loss and production. The state scale analysis revealed the usefulness of seed-applied fungicides to mitigate seedling diseases-associated soybean yield losses in Illinois, Indiana, North Carolina, and Ohio. Further, fungicide use positively influenced the soybean production and yield in Illinois and South Dakota. Taken together, use of seed-applied fungicide did not appear to be beneficial to many of the states. Our findings corroborate the observations made by a number of scientists through field scale seed-applied fungicide trials across the U.S and reiterate the importance of need base-use of seed-applied fungicides rather than being a routine practice in soybean production systems.
12
Gur, Lior, Keren Levy, Amotz Farber, Omer Frenkel, and Moshe Reuveni. "Delayed Development of Resistance to QoI Fungicide in Venturia inaequalis in Israeli Apple Orchards and Improved Apple Scab Management Using Fungicide Mixtures." Agronomy 11, no. 2 (February 23, 2021): 396. http://dx.doi.org/10.3390/agronomy11020396.
Full textAbstract:
Quinone outside inhibitors (QoI) fungicides group were introduced for commercial use against apple scab (Venturia inaequalis) in Israel in 1997. Unlike other regions in the world, in which resistance of V. inaequalis to QoI fungicides was observed within 3–5 years of use, in Israel it only occurred after 14 years of use. Field trials conducted between 2007 and 2017 showed a significant reduction in susceptibility to QoIs in northern Israel only since 2011. The delay in the development of resistance is related to limited fungicidal sprays resulting from unfavorable conditions for the pathogen. Of the 28 isolates collected from infected leaves or fruits of commercial orchards in northern Israel, 27 were resistant to the QoI fungicide Kresoxim-methyl. Amplification of the CYTB gene and sequencing of the G143A mutation region confirmed the resistance of all 27 isolates to QoIs. Resistance is demonstrated in the orchard, in vitro and molecular-based study, which forced the growers to avoid using QoIs against apple scab. We show that foliar applications of tank mixtures of systemic fungicides plus captan or prepacked fungicidal mixtures improved efficacy and can be used as a strategic approach in fungicide resistance management, including in orchards in which resistance to QoIs has been detected.
13
Berdugo, Carlos Andres, Anne-Katrin Mahlein, Ulrike Steiner, Heinz-Wilhelm Dehne, and Erich-Christian Oerke. "Sensors and imaging techniques for the assessment of the delay of wheat senescence induced by fungicides." Functional Plant Biology 40, no. 7 (2013): 677. http://dx.doi.org/10.1071/fp12351.
Full textAbstract:
Near-range and remote sensing techniques are excellent alternatives to destructive methods for measuring beneficial effects of fungicides on plant physiology. Different noninvasive sensors and imaging techniques have been used and compared to measure the effects of three fungicidal compounds (bixafen, fluoxastrobin and prothioconazole) on wheat (Triticum aestivum L.) physiology under disease-free conditions in the greenhouse. Depending on the fungicidal treatment, changes in green leaf area and yield parameters were observed. Chlorophyll fluorescence of leaves was useful for measuring differences in the effective quantum yield of PSII. Reflectance measurements of wheat leaves were highly sensitive to changes in plant vitality. The spectral vegetation indices were useful for determining the differences among treatments in terms of leaf senescence, pigments and water content. The analysis of ear and leaf surface temperature was reliable for detecting effects of fungicides on plant senescence. Using nondestructive sensors, it was possible to assess a delay in senescence of wheat due to fungicide application. Furthermore, it was deduced that sensors and imaging methods are useful tools to estimate the effects of fungicides on wheat physiology. Physiological parameters measured by the sensors were actually more sensitive than yield parameters to assess the effect caused by fungicide application on wheat physiology.
14
Reimann, Sven, and Holger B. Deising. "Inhibition of Efflux Transporter-Mediated Fungicide Resistance in Pyrenophora tritici-repentis by a Derivative of 4′-Hydroxyflavone and Enhancement of Fungicide Activity." Applied and Environmental Microbiology 71, no. 6 (June 2005): 3269–75. http://dx.doi.org/10.1128/aem.71.6.3269-3275.2005.
Full textAbstract:
ABSTRACT Populations of the causal agent of wheat tan spot, Pyrenophora tritici-repentis, that are collected from fields frequently treated with reduced fungicide concentrations have reduced sensitivity to strobilurin fungicides and azole fungicides (C14-demethylase inhibitors). Energy-dependent efflux transporter activity can be induced under field conditions and after in vitro application of sublethal amounts of fungicides. Efflux transporters can mediate cross-resistance to a number of fungicides that belong to different chemical classes and have different modes of action. Resistant isolates can grow on substrata amended with fungicides and can infect plants treated with fungicides at levels above recommended field concentrations. We identified the hydroxyflavone derivative 2-(4-ethoxy-phenyl)-chromen-4-one as a potent inhibitor of energy-dependent fungicide efflux transporters in P. tritici-repentis. Application of this compound in combination with fungicides shifted fungicide-resistant P. tritici-repentis isolates back to normal sensitivity levels and prevented infection of wheat leaves. These results highlight the role of energy-dependent efflux transporters in fungicide resistance and could enable a novel disease management strategy based on the inhibition of fungicide efflux to be developed.
15
Huang, Danling, Shumin Zheng, and Yong-Xian Cheng. "Design, Synthesis and Biological Evaluation of N-((2-phenyloxazol-4-yl)methyl) Pyrimidine Carboxamide Derivatives as Potential Fungicidal Agents." Heterocyclic Communications 26, no. 1 (January 1, 2020): 185–91. http://dx.doi.org/10.1515/hc-2020-0117.
Full textAbstract:
Abstract Twelve N-((2-phenyloxazol-4-yl)methyl) pyrimidine carboxamide derivatives were designed, synthesized, and characterized by 1H NMR, 13C NMR, and HRMS. The fungicidal activities of these new compounds against Sclerotinia sclerotiorum, Botrytis cinereal, and Colletotrichum fragariae were evaluated. The results indicated that compounds 5b, 5f, and 5g displayed potential fungicidal activities against tested fungi, especially 5f exhibited IC50 value of 28.9 mg/L against S. sclerotiorum. Moreover, the compounds 5f and 5g showed IC50 values of 54.8 mg/L and 62.2 mg/L against C. fragariae respectively, which shows that they were more active than the commercial fungicide hymexazol. The superficial structure-activity relationships were discussed, which may be of benefit for the development of fungicides and discovery of novel fungicides.
16
Manning, Paul, Krilen Ramanaidu, and G. Christopher Cutler. "Honey bee survival is affected by interactions between field-relevant rates of fungicides and insecticides used in apple and blueberry production." FACETS 2, no. 2 (September 1, 2017): 910–18. http://dx.doi.org/10.1139/facets-2017-0025.
Full textAbstract:
Certain compounds of low toxicity can increase the susceptibility of an organism to toxic substances; this is known as potentiation. Demethylation inhibiting (DMI) fungicides can potentiate insecticides by impairing the production of detoxification enzymes. As both DMI fungicides and insecticides can be used near or during crop bloom, the combination may be hazardous if exposed to pollinators. Using pesticides used in blueberry or apple production, we conducted laboratory bioassays to test how combinations of field-relevant concentrations of DMI fungicides and insecticides affected honey bee ( Apis mellifera) survival. We found propiconazole, a DMI fungicide, potentiated the toxicity of the neonicotinoid insecticide acetamiprid. We found no evidence of propiconazole potentiating field-relevant concentrations of the spinosyn insecticide spinetoram. We also found that the DMI fungicide flusilazole potentiated spinetoram but not acetamiprid. A fungicidal formulation combining pyraclostrobin and boscalid did not potentiate either insecticide. Given that bees can be simultaneously exposed to multiple pesticides, understanding the potential of pesticide potentiation and synergism may help mitigate risks associated with pollinator exposure to pesticides.
17
Nuwamanya, Andrew M., Steven Runo, and Maina Mwangi. "Farmers’ perceptions on tomato early blight, fungicide use factors and awareness of fungicide resistance: Insights from a field survey in Kenya." PLOS ONE 18, no. 1 (January 23, 2023): e0269035. http://dx.doi.org/10.1371/journal.pone.0269035.
Full textAbstract:
Early blight (EB) caused by Alternaria solani is one of the most devastating tomato diseases in Kenya and is most often managed by application of synthetic fungicides. However, there have been reports from farmers about the declining efficacy of some fungicides. These reports suggest that A. solani populations in Kenya could be developing resistance to some of the commonly used fungicides. In this study, we surveyed 175 tomato fields, sampled in 3 major tomato producing counties in Kenya, to determine the status of EB, management practices, and fungicide use factors that could contribute to development of resistance to fungicides among A. solani populations in Kenya. Data was recorded on farm characteristics, EB prevalence, fungicide usage, and farmers’ perceptions on fungicide efficacy. EB was prevalent in 85% of the fields and 90% of the farmers identified it as a major cause of yield loss. Tomato was grown all year round on 60% of the fields with only short fallow periods. All farmers reported that they were relying on fungicides for EB control and none among the cultivars grown was resistant to the disease. A total of 40 fungicide products, representing 20 active compounds with varying FRAC resistance risk levels were in use against EB. Majority (83%) of the farmers were applying fungicides at dosages and frequencies higher than those indicated on labels. Most farmers (81%) indicated that they had observed declines in effectiveness of at least one fungicide, used at EB control. This observation was more with fungicides in the strobilurin and triazole groups. These findings demonstrate that the current tomato production systems in Kenya do not take into account the risk of A. solani developing resistance to fungicides. Enhancing farmers’ knowledge of the disease and their ability to properly select and apply fungicides is therefore crucial for effective control of EB and mitigating the high risk of fungicide resistance build up.
18
Yellareddygari, S. K. R., Julie S. Pasche, Raymond J. Taylor, and Neil C. Gudmestad. "Individual Participant Data Meta-Analysis of Foliar Fungicides Applied for Potato Early Blight Management." Plant Disease 100, no. 1 (January 2016): 200–206. http://dx.doi.org/10.1094/pdis-05-15-0530-re.
Full textAbstract:
Foliar fungicides continue to be the primary means of early blight management on potato in the United States. Both premium-priced, single-site mode-of-action “specialty” fungicides and standard protectant multisite fungicides are applied, either alone or incorporated into fungicide rotation programs to combat early blight. Individual participant data meta-analysis was conducted to compare overall fungicide efficacy against early blight on potato, quantify tuber yields, and identify the most efficacious timing for fungicide applications. In this study, the specialty fungicide-based applications were compared against the standard fungicides chlorothalonil and mancozeb applied alone. Type 3 fixed effects indicated that there was a significant difference (P < 0.0001) in overall efficacy and yield among the treatments applied to manage early blight in potato. There was a significant difference (P < 0.0001) among treatments in early blight development during the growing season. Applications incorporating specialty fungicides, when compared with standard fungicides, significantly affected disease severity from vegetative growth initiation (P = 0.0139) to tuber maturation (P = 0.0009). Results demonstrate that the higher cost, specialty-fungicide-based applications were most effective for early blight management in North Dakota and Minnesota.
19
Rancāne, Regīna, Alma Valiuškaitė, Laura Ozoliņa-Pole, Guna Bundzēna, Maksims Fiļipovičs, and Neringa Rasiukevičiūtė. "The Effectiveness of Synthetic and Inorganic Substances in Different Apple Scab Control Strategies." Agriculture 14, no. 3 (February 28, 2024): 383. http://dx.doi.org/10.3390/agriculture14030383.
Full textAbstract:
A two-year trial (2021 and 2022) was performed with five different fungicide and foliar fertiliser application strategies to control apple scab (Venturia inaequalis) in integrated apple orchards in Latvia. A strategy of using inorganic fungicides or combining them with synthetic fungicides was compared to a strategy of applications with only synthetic fungicides and untreated control. Furthermore, two strategies included foliar fertilisers to determine whether they may affect apple scab used alone or combined with synthetic fungicides. The timing of the fungicide applications was based on the risk forecasted by the decision support system RIMpro, and fertilisers were used at certain growth stages of the crop. The disease incidence on untreated fruits on cv. Auksis ranged from 38.3% to 59.6%, and on cv. Ligol from 99.3% to 99.5%. Strategies including synthetic fungicides were the most effective against scab on shoot leaves and fruits. The strategy using only inorganic fungicides was effective for low-inoculum orchards. Combining synthetic and inorganic fungicides provided the best apple scab control strategy on fruits, likely helping reduce the resistance selection pressure and residues of synthetic fungicides. Foliar fertilisers were insufficient to control apple scab; they would supplement existing scab fungicide programs.
20
Wu, Ping-Hu, Hao-Xun Chang, and Yuan-Min Shen. "Effects of synthetic and environmentally friendly fungicides on powdery mildew management and the phyllosphere microbiome of cucumber." PLOS ONE 18, no. 3 (March 8, 2023): e0282809. http://dx.doi.org/10.1371/journal.pone.0282809.
Full textAbstract:
Modern agricultural practices rely on synthetic fungicides to control plant disease, but the application of these fungicides has raised concerns regarding human and environmental health for many years. As a substitute, environmentally friendly fungicides have been increasingly introduced as alternatives to synthetic fungicides. However, the impact of these environmentally friendly fungicides on plant microbiomes has received limited attention. In this study, we used amplicon sequencing to compare the bacterial and fungal microbiomes in the leaves of powdery mildew-infected cucumber after the application of two environmentally friendly fungicides (neutralized phosphorous acid (NPA) and sulfur) and one synthetic fungicide (tebuconazole). The phyllosphere α-diversity of both the bacterial and fungal microbiomes showed no significant differences among the three fungicides. For phyllosphere β-diversity, the bacterial composition exhibited no significant differences among the three fungicides, but fungal composition was altered by the synthetic fungicide tebuconazole. While all three fungicides significantly reduced disease severity and the incidence of powdery mildew, NPA and sulfur had minimal impacts on the phyllosphere fungal microbiome relative to the untreated control. Tebuconazole altered the phyllosphere fungal microbiome by reducing the abundance of fungal OTUs such as Dothideomycetes and Sordariomycetes, which included potentially beneficial endophytic fungi. These results indicated that treatments with the environmentally friendly fungicides NPA and sulfur have fewer impacts on the phyllosphere fungal microbiome while maintaining the same control efficacy as the synthetic fungicide tebuconazole.
21
Yan, Xiaojing, Shuning Chen, Wei Sun, Xiaoxin Zhou, Daibin Yang, Huizhu Yuan, and Daoquan Wang. "Primary Mode of Action of the Novel Sulfonamide Fungicide against Botrytis cinerea and Field Control Effect on Tomato Gray Mold." International Journal of Molecular Sciences 23, no. 3 (January 28, 2022): 1526. http://dx.doi.org/10.3390/ijms23031526.
Full textAbstract:
Botrytis cinerea is considered an important plant pathogen and is responsible for significant crop yield losses. With the frequent application of commercial fungicides, B. cinerea has developed resistance to many frequently used fungicides. Therefore, it is necessary to develop new kinds of fungicides with high activity and new modes of action to solve the increasingly serious problem of resistance. During our screening of fungicide candidates, one novel sulfonamide compound, N-(2-trifluoromethyl-4-chlorphenyl)-2-oxocyclohexyl sulfonamide (L13), has been found to exhibit good fungicidal activity against B. cinerea. In this work, the mode of action of L13 against B. cinerea and the field control effect on tomato gray mold was studied. L13 had good control against B. cinerea resistant to carbendazim, diethofencarb, and iprodione commercial fungicides in the pot culture experiments. SEM and TEM observations revealed that L13 could cause obvious morphological and cytological changes to B. cinerea, including excessive branching, irregular ramification or abnormal configuration, and the decomposition of cell wall and vacuole. L13 induced more significant electrolyte leakage from hyphae than procymidone as a positive control. L13 had only a minor effect on the oxygen consumption of intact mycelia, with 2.15% inhibition at 50 μg/mL. In two locations over 2 years, the field control effect of L13 against tomato gray mold reached 83% at a rate of 450 g ai ha−1, better than the commercial fungicide of iprodione. Moreover, toxicological tests demonstrated the low toxicological effect of L13. This research seeks to provide technical support and theoretical guidance for L13 to become a real commercial fungicide.
22
Wyenandt, Christian A., Wesley L. Kline, and Daniel L. Ward. "Effect of Fungicide Program on the Development of Downy Mildew in Three Cucurbit Crops in New Jersey." Plant Health Progress 18, no. 3 (January 1, 2017): 181–85. http://dx.doi.org/10.1094/php-04-17-0026-phm.
Full textAbstract:
From 2014 to 2016, five fungicide programs of varying fungicide efficacy were evaluated for the control of cucurbit downy mildew (Pseudoperonospora cubensis) on three different cucurbit crops at the Rutgers Agricultural Research and Extension Center (RAREC) in Bridgeton, NJ. The five fungicide programs were: (i) no fungicide input; (ii) low-input (chlorothalonil only); (iii) medium-input (protectant + 2 downy mildew-specific fungicides [Tanos, Curzate]); (iv) high-input (protectant + 2 downy mildew-specific fungicides [Ranman, Presidio]); or (v) high-input (protectant + 3 downy mildew-specific fungicides [Previcur Flex, Ranman, Zampro]). The three cucurbit crops were cucumber cv. Marketmore 76, zucchini cv. Reward (summer squash), and acorn squash cv. Taybelle (winter squash). In 2014, only cucumber was infected by the pathogen. In 2015 and 2016, all three cucurbit hosts were infected by downy mildew at varying severities suggesting that the P. cubensis population may have differed compared with 2014. In all three years control of downy mildew was significantly higher when downy mildew-specific fungicides were included in weekly rotations. In some years, no fungicides, broad-spectrum fungicides only, or fungicides with moderate or lower efficacy for downy mildew may provide adequate control on certain cucurbit crop species depending on the current cucurbit downy mildew pathogen population.
23
Gikas, Georgios D., Paraskevas Parlakidis, Theodoros Mavropoulos, and Zisis Vryzas. "Particularities of Fungicides and Factors Affecting Their Fate and Removal Efficacy: A Review." Sustainability 14, no. 7 (March 29, 2022): 4056. http://dx.doi.org/10.3390/su14074056.
Full textAbstract:
Systemic fungicide use has increased over the last decades, despite the susceptibility of resistance development and the side effects to human health and the environment. Although herbicides and insecticides are detected more frequently in environmental samples, there are many fungicides that have the ability to enter water bodies due to their physicochemical properties and their increasing use. Key factors affecting fungicide fate in the environment have been discussed, including the non-target effects of fungicides. For instance, fungicides are associated with the steep decline in bumblebee populations. Secondary actions of certain fungicides on plants have also been reported recently. In addition, the use of alternative eco-friendly disease management approaches has been described. Constructed Wetlands (CWs) comprise an environmentally friendly, low cost, and efficient fungicide remediation technique. Fungicide removal within CWs is dependent on plant uptake and metabolism, absorption in porous media and soil, hydrolysis, photodegradation, and biodegradation. Factors related to the efficacy of CWs on the removal of fungicides, such as the type of CW, plant species, and the physicochemical parameters of fungicides, are also discussed in this paper. There are low-environmental-risk fungicides, phytohormones and other compounds, which could improve the removal performance of CW vegetation. In addition, specific parameters such as the multiple modes of action of fungicides, side effects on substrate microbial communities and endophytes, and plant physiological response were also studied. Prospects and challenges for future research are suggested under the prism of reducing the risk related to fungicides and enhancing CW performance.
24
Ali, Md Emran, Owen Hudson, Will H. Hemphill, Timothy B. Brenneman, and Jonathan E. Oliver. "First Report of Resistance to Pyraclostrobin, Boscalid, and Thiophanate-methyl in Colletotrichum gloeosporioides from Blueberry in Georgia." Plant Health Progress 20, no. 4 (January 1, 2019): 261–62. http://dx.doi.org/10.1094/php-08-19-0058-br.
Full textAbstract:
Colletotrichum gloeosporioides causes anthracnose fruit rot and leaf spot on blueberries. For controlling anthracnose, blueberry growers mostly rely on pre- and postharvest fungicide applications in addition to orchard sanitation. Single-site fungicides including quinone outside inhibitors (QoIs), such as pyraclostrobin and azoxystrobin as well as fungicides containing the succinate dehydrogenase inhibitor (SDHI) boscalid are used frequently to control anthracnose rots and other diseases on blueberry; however, development of fungicide resistance is a real risk because a limited number of fungicides are now available for blueberry disease management. In 2019, three isolates of C. gloeosporioides were cultured from blueberry fruit collected from southern highbush blueberry cultivar ‘Farthing’ in two commercial blueberry fields in Pierce County, Georgia, where ripe rot had been a problem. Fungicide sensitivity tests were conducted using a mycelial growth inhibition assay as described previously. A total of nine fungicides were evaluated to determine the sensitivity of these C. gloeosporioides isolates. All three isolates were resistant to thiophanate-methyl, the QoI fungicide pyraclostrobin, and the SDHI fungicide boscalid. These findings suggest that continuous monitoring of fungicide resistance is necessary to avoid the unwarranted application of single-site fungicides.
25
Singh, Aparna, Satyveer Singh Meena, and Vikash k. "Purchasing Behaviour of Farmers for Bio-fungicide in Meerut District of Uttar Pradesh." Indian Journal of Extension Education 59, no. 3 (2023): 149–52. http://dx.doi.org/10.48165/ijee.2023.59329.
Full textAbstract:
In this study, an attempt was made to examine the variables affecting farmers’ satisfaction with bio fungicide use, the variables affecting their buying behaviour for the product and constraints faced by the farmers in usage of bio-fungicides. A total of 100 farmers were selected on the basis of snowball sampling. RBQ mean was calculated to find out the most influencing factors for purchasing of bio fungicide by the farmers. Garrett’s standard procedure was adopted to determine the significance of a number of different factors as expressed by respondents in the use of bio-fungicides. It was found that the retailers influence, quality, price of positives and the opinion leaders with implant agency were the important factors that affect the purchasing decision of farmers. Further, a substantial percentage of farmers in the research area were quite satisfied with the bio-fungicide’s efficacy, followed by its relative quality and history of widespread usage.
26
Hagan, A. K., and J. R. Akridge. "Synthetic and Biorational Fungicides Compared for the Control of Three Foliar Diseases of Flowering Dogwood." Journal of Environmental Horticulture 25, no. 3 (September 1, 2007): 157–65. http://dx.doi.org/10.24266/0738-2898-25.3.157.
Full textAbstract:
Abstract The biorational fungicides Neem Concentrate, SunSpray Ultra Fine Oil®, Rhapsody® were compared with the synthetic fungicides Eagle® 40W, Immunox®, Liquid Systemic Fungicide®, and 3336™ 50W for the control of spot anthracnose, Cercospora leaf spot, and powdery mildew on ‘Rubra’ flowering dogwood. In 2003, 2004, and 2005, fungicide treatments were applied at label rates at 1- and/or 2-week intervals over a period that coincided with the onset spot anthracnose and powdery mildew but before the appearance of Cercospora leaf spot. With few exceptions, the synthetic fungicides gave better control of the above diseases than biorational fungicides. Eagle 40W, Immunox, Liquid Systemic Fungicide, and 3336 50W gave equal control of the bract and leaf spot phases of spot anthracnose. Most notable was the carryover of control of the bract spot phase of spot anthracnose into the spring of the following year with the synthetic fungicides. While some control of spot anthracnose was seen in at least one year with the biorational fungicides, none was as effective as the synthetic fungicides. In 2003 and 2004, Neem Concentrate, SunSpray Ultra Fine Oil, and Rhapsody, when applied weekly controlled powdery mildew as effectively as the synthetic fungicides. Efficacy of the biorational fungicides declined under severe powdery mildew pressure in 2005. While Cercospora leaf spot development was slowed by the Eagle 40W, Liquid Systemic Fungicide, and 3336 50W, the biorational fungicides as well as the retail product Immunox also gave some control. An objectionable mottling of the leaves was noted on the flowering dogwood treated with SunSpray Ultra Fine Oil. Control of these diseases with the synthetic or biorational fungicides did not result in an increase in tree height or trunk diameter. While the biorational fungicides demonstrated sufficient efficacy for controlling powdery mildew on flowering dogwood in the landscape, they often failed to provide the level of control of this disease as well as spot anthracnose and Cercospora leaf spot needed to produce quality container- and field-grown nursery stock.
27
Maslennikova, Sofia, Alexander Sarychev, and Oksana Reznikova. "Formation of productivity of spring barley depending on the use of fungicides in the conditions of black soils of the Volgograd region." E3S Web of Conferences 463 (2023): 01040. http://dx.doi.org/10.1051/e3sconf/202346301040.
Full textAbstract:
The article discusses the results of studies on the study of zoned varieties of spring barley in the zone of black soils and their reaction to the use of fungicides when treating seeds. It was found that in years with different climatic characteristics, there are differences in varieties in the duration of phenological phases. The longest growing season was observed for the Novonikolaevsky variety, and the shortest for the Prairie variety. The best results on germination and safety of plants were obtained on the variant with the Novonikolaevsky variety, while on all varieties it was noted that the use of a three-component fungicide promotes better germination and safety than on options with a single-component fungicide and without the use of fungicides. Analysis of the productivity of varieties showed that the studied varieties had different yields depending on the use of seed protectants. The yield of the Novonikolaevsky variety was the highest in all studied options for using fungicides compared to the Prairie variety. In the variant using the Vial Trio fungicide with the active ingredients Prochloraz 120 g/l, Thiabendazole 30 g/l, Cyproconazole 5 g/l, it was 3.41 t/ha. Thus, it can be recommended that agricultural producers cultivate the spring barley variety Novonikolaevsky, and carry out the main seed treatment with the fungicidal preparation Vial Trio.
28
Ribeiro, Francisco De Carvalho, Eduardo Andrea Lemus Erasmo, Francileia De Sousa Rocha, Eduardo Bezerra De Moraes, and Edilson Pereira De Matos. "Associação de fungicida protetor com fungicidas sistêmicos no controle de mancha-alvo na cultura da soja." Revista Verde de Agroecologia e Desenvolvimento Sustentável 11, no. 5 (December 31, 2016): 51. http://dx.doi.org/10.18378/rvads.v11i5.4273.
Full textAbstract:
<p>A mancha-alvo, cujo agente causal é o fungo <em>Corynespora cassiicola</em> vem ganhando importância entre as doenças na cultura da soja, principalmente na região de cerrado, em função de sua elevada severidade e potencial degenerativo à planta. O controle químico de doenças das plantas é uma medida que na maioria dos casos é eficiente e economicamente viável para garantir grandes produções e qualidade de produção. Objetivou-se nesse trabalho avaliar a eficiência da mistura de fungicida protetor aplicado em combinações com fungicidas sistêmicos visando o controle de mancha alvo na cultura da soja. O experimento foi conduzido no ano agrícola 2014/2015 em condições de campo na fazenda Boa Esperança, situada no município de Porto Nacional – TO. O delineamento experimental foi o de blocos ao acaso com quatro repetições, num total de seis tratamentos distintos. Foram realizadas as seguintes avaliações: Severidade da doença, desfolha, índice de área verde, AACPD, massa de 1.000 grãos e produtividade grãos. A aplicação de fungicidas promoveu menor progresso da mancha-alvo em soja, redução na desfolha, aumento no índice de área verde, maior massa de 1.000 grãos e maior produtividade de grãos. A eficiência de controle de mancha-alvo (<em>C. cassiicola</em>) na cultura da soja melhorou conforme foi aumentando o número de aplicações de mancozebe associado aos fungicidas sistêmicos.</p><p align="center"><strong><em>Fungicidal protective association with systemic fungicides in the target spot control in soybean</em></strong></p><p><strong>Abstract</strong><strong>: </strong>The spot target whose causal agent is the fungus <em>Corynespora cassiicola</em> is gaining importance among the diseases in soybean, especially in the cerrado region, due to its high severity and potential degenerative the plant. Chemical control of plant diseases is a measure which in most cases is efficient and economically feasible to ensure high production and quality production. Aim of this study was to evaluate the effectiveness of protective fungicide mixture used in combination with systemic fungicides aiming at the target spot control in soybean. The experiment was conducted in the agricultural year 2014/2015 in field conditions on the farm Good Hope, in the municipality of Porto Nacional – TO. The experimental design was a randomized block design with four replications, a total of six different treatments. The following evaluations were performed: Severity of disease, defoliation, green area index, AUDPC, mass of 1.000 grains and grain productivity. The application of fungicides promoted less progress of the target spot in soybeans, reduction in defoliation, increased green area index, the greater mass of 1.000 grains and higher grain yield. The Mancha control efficiency target (<em>C. cassiicola</em>) in soybean improved as was increasing the number of mancozeb applications associated with systemic fungicides.</p><p><strong> </strong></p>
29
Orina, Aleksandra, Olga Gavrilova, and Tatiana Gagkaeva. "The effect of fungicides on growth of Fusarium fungi in vitro." BIO Web of Conferences 18 (2020): 00022. http://dx.doi.org/10.1051/bioconf/20201800022.
Full textAbstract:
Four different fungicides that recommended to control seed-borne pathogens, were tested in this study. Three fungicides contain singly pyraclostrobin (200 g/L), thiram (400 g/L), fludioxonil (25 g/L), and one fungicide contains together imazalil, metalaxyl, and tebuconazole (50, 40, and 30 g/L, respectively). Comparative assessment of the fungicides at four concentrations of active substance (10, 100, 1 000, and 10 000 ppb) on the growth of ten strains of Fusarium spp. was studied in vitro tests. To visualize the effect of fungicides on fungal growth the strains were cultivated in 50 mL liquid Czapek medium containing fungicides in the range of concentrations. The fungicide based on pyraclostrobin was the most effective in growth inhibition of Fusarium fungi. Broadly, the using of this fungicide is confident way to control Fusarium species, which are serious threat to crop production. The sensitivity of F. acuminatum, F. graminearum, F. semitectum, F. culmorum, F. sporotrichioides, F. equiseti strains to fungicides was higher in compare with the strains belonging to F. oxysporum, F. solani, F. verticillioides, and F. proliferatum.
30
Chapman, Kimberly S., George W. Sundin, and Janna L. Beckerman. "Identification of Resistance to Multiple Fungicides in Field Populations of Venturia inaequalis." Plant Disease 95, no. 8 (August 2011): 921–26. http://dx.doi.org/10.1094/pdis-12-10-0899.
Full textAbstract:
Venturia inaequalis, the causal agent of apple scab, is controlled primarily by fungicides. Long-term, extensive fungicide use has led to the development of resistance to multiple fungicides. To assess fungicide resistance, isolates of V. inaequalis were collected from Indiana and Michigan orchards. Single-spore derived isolates were evaluated by mycelium growth assays with previously determined discriminatory doses on media containing dodine, kresoxim-methyl, myclobutanil, or thiophanate-methyl. Of 195 isolates tested, 5.2, 0.7, 57.0, and 92.6% of isolates were found to be resistant to dodine, kresoxim-methyl, myclobutanil, and thiophanate-methyl, respectively. This is the first report of kresoxim-methyl field resistance in these states. Isolates resistant or shifted to a single fungicide were often found to have multiple fungicide resistance. Of all isolates tested, 38% were identified as resistant or shifted to two fungicides, and 12% were resistant or shifted to all four fungicides tested. No fitness penalty was found for isolates resistant to multiple fungicides based on a statistical analysis of mycelial growth and conidial production.
31
Mueen Uddin, Taimoor Khan, Faheem Ahmed, Juma Khan Babar, Muhammad Ejaz, Faisal Adnan, Rehan Fareed, and Hidayatullah Kakar. "Optimizing Fungicide Sprays to Tackle Powdery Mildew (Uncinula necator) At The Right Time For healthy grapes production." BioSight 4, no. 4 (October 10, 2023): 28–40. http://dx.doi.org/10.46568/bios.v4i4.154.
Full textAbstract:
Introduction: Powdery mildew, caused by the fungus Uncinula necator, is a prevalent and harmful disease affecting grapevines, resulting in decreased fruit set and yield. This study aimed to evaluate the effectiveness of various fungicides and spray timings in managing U. necator in grape vineyards. Methods: A field trial was conducted in Pishin, Balochistan in 2020, employing a randomized complete block design with two factors: four fungicides (control, protective fungicide-Bordeaux mixture, curative fungicide-Elite 45 wp, systemic fungicide-Quintec) and four spray timings (dormant spray, bud break, one week before bloom, and berry formation). Results: The findings revealed significant variations in disease severity (PDI) among leaves, inflorescence, and bunches across different fungicides, spray timings, and their interactions. Application of the protective fungicide one week before bloom proved highly effective in preventing U. necator infection, resulting in the lowest PDI values for leaves (0.44%), inflorescence (0.67%), and bunches (0.0%). Curative fungicides sprayed at bloom stage also reduced PDI for inflorescence (2.17%) and bunches (3.56%). Systemic fungicides applied during berry formation exhibited lower PDI for inflorescence (6.44%) and bunches (4.0%) compared to other fungicides. The highest grape production (27.10 t ha-1) was achieved with the protective fungicide sprayed at bloom stage, followed by the curative fungicide at bloom stage (25.87 t ha-1). The negative and highly significant relationship (R2=0.809) between PDI of leaves and grape yield indicated that higher disease severity led to decreased yield. Conclusion: In conclusion, a protective fungicide spray before bloom, followed by a systemic fungicide spray at berry formation, effectively controls U. necator and ensures healthier and higher grape yields.
32
TERRA, MICHELLE F., NATHASHA de A. LIRA, FABIANA R. F. PASSAMANI, WILDER DOUGLAS SANTIAGO, MARIA das GRAÇAS CARDOSO, and LUÍS ROBERTO BATISTA. "Effect of Fungicides on Growth and Ochratoxin A Production by Aspergillus carbonarius from Brazilian Wine Grapes." Journal of Food Protection 79, no. 9 (September 1, 2016): 1508–16. http://dx.doi.org/10.4315/0362-028x.jfp-16-037.
Full textAbstract:
ABSTRACT Prevention in the field of mycotoxin-producing fungi is the most effective strategy for controlling the presence of mycotoxins in foods. Chemical fungicides are widely used to protect crops, so their implications on mycotoxin production need to be considered. Therefore, the aim of this study was to evaluate the effect in vitro and on grapes of five fungicides commonly used on grape cultures in Brazil on Aspergillus carbonarius growth and ochratoxin A (OTA) production. At the doses recommended by manufacturers, most fungicides significantly reduced A. carbonarius growth and OTA production in vitro, whereas this effect was influenced by the type of fungicide, dose, and temperature. Temperature was the main factor that influenced the effectiveness of fungicides. In general, at 15°C, fungicides showed the greatest reduction on fungal growth and OTA production. Fungicide effect on grapes was different to that on a semisynthetic grape medium. All fungicide doses were not effective at controlling A. carbonarius in grapes. Thus, the direct effect of fungicides on grapes must be studied to obtain a better approximation of field conditions. The results indicate that the use of fungicides at the doses recommended by manufacturers is better than the application at low doses. This study showed that at the lowest doses, where fungal growth is not inhibited, fungicides positively stimulate OTA production.
33
Zhao, Dongxu, Yang Zhang, Zhaoyang Jin, Ruxiao Bai, Jun Wang, Li Wu, and Yujian He. "Benzalkonium Chloride and Benzethonium Chloride Effectively Reduce Spore Germination of Ginger Soft Rot Pathogens: Fusarium solani and Fusarium oxysporum." Journal of Fungi 10, no. 1 (December 22, 2023): 8. http://dx.doi.org/10.3390/jof10010008.
Full textAbstract:
Ginger soft rot is a serious soil-borne disease caused by Fusarium solani and Fusarium oxysporum, resulting in reduced crop yields. The application of common chemical fungicides is considered to be an effective method of sterilization, and therefore, they pose a serious threat to the environment and human health due to their high toxicity. Benzalkonium chloride (BAC) and benzethonium chloride (BEC) are two popular quaternary ammonium salts with a wide range of fungicidal effects. In this study, we investigated the fungicidal effects of BAC and BEC on soft rot disease of ginger as alternatives to common chemical fungicides. Two soft rot pathogens of ginger were successfully isolated from diseased ginger by using the spread plate method and sequenced as F. solani and F. oxysporum using the high-throughput fungal sequencing method. We investigated the fungicidal effects of BAC and BEC on F. solani and F. oxysporum, and we explored the antifungal mechanisms. Almost complete inactivation of spores of F. solani and F. oxysporum was observed at 100 mg/L fungicide concentration. Only a small amount of spore regrowth was observed after the inactivation treatment of spores of F. solani and F. oxysporum in soil, which proved that BAC and BEC have the potential to be used as an alternative to common chemical fungicides for soil disinfection of diseased ginger.
34
Balaz, Jelica, and Tatjana Knezevic. "Efficiency of more recent fungicides in control of apple scab and powdery mildew." Pesticidi 18, no. 3 (2003): 175–85. http://dx.doi.org/10.2298/pif0303175b.
Full textAbstract:
Apple scab (V. inaequalis) and powdery mildew (P. leucotricha) are most economicaly important diseases of apple. Chemical measures are of the highest importance in controlling these diseases. There is great number of fungicides on the market. Fungicide choice and time of application depend upon mechanism of their action. Experiments on controlling apple scab and powdery mildew are carried out in 1998/99 and 2002. in different locations in Vojvodina. According to the obtained results the highest efficacy in the control of apple scab and powdery mildew have performed pesticides from strobilurin group (Stroby-kresoxim-methyl and Zato 50 WG-trifloxystrobin)as well as fungicides belonging to the new group of fungicides (Clarinet). In the disease control of the apple high efficacy have also performed DMI fungicides such as Score 250-EC (in control of apple scab). Topas-lOOE and Webeton (in control of powder) mildew). Lower efficacy have performed fungicides with preventive activity such as combination of Venturin S-50+Cosan. Unpublished data from previous studies (1995-1997) of the fungicide Chorus (cyprodinil) biological efficacy also suggested that this new generation fungicide from anylopyrimidin group showed better efficacy than fungicides belonging to former DMI fungicides, as well as contact ones.
35
Poromarto, S. H., Hadiwiyono, Supyani, Supriyadi, and F. I. Permatasari. "Fungicide resistance of Fusarium oxysporum f.sp. cepae isolated from shallot in Brebes." IOP Conference Series: Earth and Environmental Science 1180, no. 1 (May 1, 2023): 012033. http://dx.doi.org/10.1088/1755-1315/1180/1/012033.
Full textAbstract:
Abstract Brebes, Central Java is the largest shallot centre in Indonesia. Shallot are planted intensively in this area. The most detrimental disease of the plants is moler caused by Fusarim oxysporum f.sp. cepae, FOCe. Fungicide applications are carried out periodically every 3-5 days. However, the disease severity is still quite high. There is even a tendency to increase every year. In addition, continuous use of the fungicides can cause adverse effects on the control itself, such as the emergence of fungicide resistance. Field testing aims to evaluate the effectiveness of fungicides against moler disease. Lab testing to evaluate FOCe resistance to fungicides. The fungicides used in this research are the fungicide Brands widely used by farmers in this area. The efficacy test results showed that the three Brands were not effective (efficacy below 50%). There are indications that FOCe is resistant to two merks of fungicides with active ingredients, Chlorothalonil and Propineb.
36
Borzykh, O., V. Sergienko, M. Dzham, O. Shyta, and S. Mykhaylenko. "Fungicidal control of the most common onion mycoses during the growing season." Karantin i zahist roslin, no. 2 (June 21, 2023): 3–9. http://dx.doi.org/10.36495/2312-0614.2023.2.3-9.
Full textAbstract:
Goal. To investigate the effectiveness of fungicidal control of the most common onion diseases during the growing season.
Methods. Informational and analytical (collection of materials and analysis of literary sources), field research (setting up experiments, carrying out treatments and records of plant damage by diseases, monitoring the development of plants, harvesting), phytopathological (determination and identification of pathogens), mathematical and statistical (processing of results studies). Experiments were conducted on different varieties and hybrids using modern fungicides with different active substances.
Results. During the years of research, onion crops were dominated by mycoses, namely, peronosporosis, alternaria, stemphylliosis, and fusarium wilt. Downy mildew and leaf spots were observed on all varieties and hybrids. The investigated fungicides most effectively controlled the development of downy mildew of onions. Their efficiency during the growing season averaged 55.1—100%, depending on the drug, the degree of disease development and the variety. The highest effectiveness against downy mildew of onions was provided by fungicides Fandango 200 ES, KE (fluoxystrobin, 100 g/l + proteoconazole, 100 g/l) at the rate of 1.25 l/ ha and Signum VG (boskalid, 267 g/ kg + pyraclostrobin, 67 g/ kg) — 1.5 kg/ ha. Fungicides were 45.8—89.1% effective against leaf spots (alternaria and stemphyllosis), 57.9—70.5% against fusarium wilt. Treatments with fungicides, due to the reduction of plant damage by diseases, contributed to the increase in onion yield by 1.3—6.9 t/ha, depending on the variety and preparation. Among the studied varieties, the highest yield was obtained on the Medusa variety (40.7 t/ha), among fungicides, the highest yield increase was provided by Fandango 200 ES, KE fungicide (1.25 l/ha).
Conclusions. Fungicides effectively controlled the main mycoses of onion (peronosporosis, alternariosis, stemphyllosis and fusarium wilt) during the growing season. The effectiveness of fungicides against onion diseases was 45.8—100%, depending on the type of disease, drug and crop variety. The highest protective effect of fungicides was provided against downy mildew of onions. The yield of the researched varieties and hybrids increased by an average of 5—25% due to the reduction of plant damage by diseases. The highest technical efficiency against identified diseases and increase in onion yield was obtained by using Fandango 200 ES, KE fungicide with a consumption rate of 1.25 l/ha.
37
Munkvold, G. P., and J. K. O'Mara. "Laboratory and Growth Chamber Evaluation of Fungicidal Seed Treatments for Maize Seedling Blight Caused by Fusarium Species." Plant Disease 86, no. 2 (February 2002): 143–50. http://dx.doi.org/10.1094/pdis.2002.86.2.143.
Full textAbstract:
The performance of seed treatment products for maize usually is evaluated in field experiments, where it is difficult to assess their effects on specific important pathogens such as fungi in the genus Fusarium. To evaluate three fungicidal seed treatments (captan, difenoconazole, and fludioxonil) against six Fusarium species that infect maize seed or seedlings, we conducted experiments in the laboratory and in growth chambers. In the laboratory experiments, treated and nontreated seeds of two maize hybrids were incubated on the surface of an agar medium colonized by each of 12 Fusarium isolates. The fungi did not reduce seed germination, but most Fusarium isolates caused decay of the seed and radicle, and arrested the development of the radicle. All three fungicides significantly reduced the colonization and decay of the seeds and radicles by Fusarium isolates and resulted in greater radicle lengths, but there were significant interactions between the effects of fungicide treatments and Fusarium isolates. Overall, difenoconazole was the most effective fungicide for the prevention of seed colonization and decay. Fludioxonil was overall the most effective fungicide in terms of increased radicle length, particularly when seed was exposed to isolates of F. graminearum, which were among the most aggressive isolates in the experiments. In the growth chamber experiments, seeds were planted in a Fusarium-infested potting medium, which resulted in lower emergence, shoot length, root length, and dry weight of seedlings compared to the noninfested control. Some isolates also caused root rot symptoms. All three fungicides significantly improved shoot and root length and root health, difenoconazole and fludioxonil significantly improved emergence, and only difeno-conazole significantly improved dry weight compared to the nontreated control. There were significant rank correlations between the results of the laboratory and growth chamber experiments in terms of relative aggressiveness of the isolates and relative efficacy of the fungicides. The laboratory experiments were more sensitive in terms of detecting differences in fungicide performance. These results indicate that all three fungicides were effective against Fusarium, but difenoconazole and fludioxonil generally were more effective than captan; the fungicides also differed in efficacy against different Fusarium species.
38
Mesterházy, Á., T. Bartók, and C. Lamper. "Influence of Wheat Cultivar, Species of Fusarium, and Isolate Aggressiveness on the Efficacy of Fungicides for Control of Fusarium Head Blight." Plant Disease 87, no. 9 (September 2003): 1107–15. http://dx.doi.org/10.1094/pdis.2003.87.9.1107.
Full textAbstract:
Attempts to control Fusarium head blight (FHB) with fungicides have been highly variable. Variability is caused by cultivar resistance, fungicide efficacy, fungicide coverage, timing, and pathogen aggressiveness. In this research, fungicides were tested on winter wheat cultivars with different levels of resistance to FHB using different isolates of Fusarium graminearum and F. culmorum to evaluate the role of host resistance and isolate aggressiveness on severity of FHB. Fungicides were applied to groups of wheat heads to provide full coverage. Incidence and severity of FHB was measured by the severity of head symptoms, percentage of Fusarium-damaged kernels (FDK), yield loss, and deoxynivalenol (DON) contamination. Development of FHB was affected by fungicides, cultivars, fungal isolates, and most of the two-way interactions of these variables. Among the fungicides tested, those containing tebuconazole tended to be more effective in reducing FHB. Reduction of disease in susceptible cultivars may not be adequate to produce marketable yields under conditions of high disease pressure. In most cases, if a fungicide reduced FHB visual symptoms, similar decreases were detected in yield loss, DON concentration, and FDK reaction. In 1998, an increase in DON contamination compared with the Fusarium check was observed with azoxystrobin and carbendazim on the more susceptible cultivar. This increase in DON with some fungicide requires additional research. Research to develop more resistant cultivars, better spraying technology, and more effective fungicides is also needed.
39
Peever, Tobin L., and Michael G. Milgroom. "Fungicide Resistance—Lessons for Herbicide Resistance Management?" Weed Technology 9, no. 4 (December 1995): 840–49. http://dx.doi.org/10.1017/s0890037x00024313.
Full textAbstract:
Resistance to agricultural fungicides has increaséd dramatically in the past twenty years, following the introduction of systemic fungicides. Disease control failures associated with fungicide resistance have occurred with many classes of fungicides and in many genera of plant-pathogenic fungi. In some cases, resistance evolved extremely rapidly making the chemicals ineffective for disease control only a few years after they were introduced.The rapid development of resistance to systemic fungicides has led to efforts to develop strategies to avoid or delay the evolution of fungicide resistance in plant pathogen populations. Despite a widespread interest in managing fungicide resistance, very few experimental studies have been performed to elucidate the important factors controlling resistance development. Most fungicide resistance studies have consisted of anecdotal field observations which have rarely been followed up with experimentation. In order to understand what factors affect the evolution of resistance, and to use this information to design effective resistance management strategies, more experimental studies are required.
40
Gasratova, Natalya, and Darya Pashkova. "Application of a modified mathematical model “consumer – resource” to justify the periods of treatment of potato late blight with fungicides." E3S Web of Conferences 486 (2024): 03012. http://dx.doi.org/10.1051/e3sconf/202448603012.
Full textAbstract:
Potato late blight is a harmful disease. Treatment of fields with fungicides is the main method of combating this phytopathology. The work presents a modified mathematical model “consumer - resource” - this is a system of partial differential equations, which contains a step function with the help of which fungicidal treatment can be successfully modeled. The system was solved numerically. Based on the modeling results, it is possible to successfully simulate the development of leaf damage during the growing season without and with fungicide treatment. Thus, knowing the duration of action of the drugs and assuming how intensively late blight will develop, it is possible to model different combinations of fungicides and spraying times. This circumstance can be successfully implemented into decision support systems for agricultural enterprises.
41
Price, Paul P., Myra A. Purvis, Guohong Cai, Guy B. Padgett, Clark L. Robertson, Raymond W. Schneider, and Sebastian Albu. "Fungicide Resistance in Cercospora kikuchii, a Soybean Pathogen." Plant Disease 99, no. 11 (November 2015): 1596–603. http://dx.doi.org/10.1094/pdis-07-14-0782-re.
Full textAbstract:
Isolates of Cercospora kikuchii, a soybean (Glycine max) pathogen causing Cercospora leaf blight and purple seed stain, were tested to determine baseline sensitivities (n = 50) to selected quinone outside inhibitor (QoI) fungicides by conducting radial growth assays on fungicide-amended media. Baseline effective fungicide concentration to inhibit 50% of fungal radial growth (EC50) values were compared with EC50 values for isolates collected in 2011 (n = 50), 2012 (n = 50), and 2013 (n = 36) throughout soybean-producing areas in Louisiana. Median EC50 values for isolates subjected to QoI fungicides were significantly (P = 0.05) higher across all 3 years. Cross-resistance to QoI fungicides was observed in resistant isolates collected in 2011 to 2013. Discriminatory doses were developed for QoI fungicides to distinguish between sensitive and resistant isolates. On average, 89% of all isolates screened in 2011 to 2013 were resistant to QoI fungicides. At a discriminatory dose of thiophanate methyl (TM), a methyl benzimidazole carbamate (MBC) fungicide, at 5 μg/ml, resistance was detected in the 2000, 2011, 2012, and 2013 collections at 23, 38, 29, and 36%, respectively. Isolates exhibiting multiple resistance to QoI fungicides and TM also were detected in 2011, 2012, and 2013 at frequencies of 34, 26, and 31%, respectively. Based on these results, Cercospora leaf blight management strategies in Louisiana using solo applications of QoI or MBC fungicides in soybean should be reconsidered.
42
Moore, M. S., G. B. Follas, G. C. Hagerty, and R. M. Beresford. "Carboxylic acid amide (CAA) fungicide resistance prevention strategy." New Zealand Plant Protection 61 (August 1, 2008): 134–36. http://dx.doi.org/10.30843/nzpp.2008.61.6796.
Full textAbstract:
CAA fungicides are currently represented in New Zealand by the three active ingredients dimethomorph iprovalicarb and mandipropamid They are currently registered in New Zealand for use against oomycete fungi in grapes onions potatoes and lettuce These fungicides are considered to have low to medium risk of resistance development and resistance management is recommended by the Fungicide Resistance Action Committee (FRAC) in Europe Guidelines are presented for fungicide use that will avoid or delay the development of resistance to CAA fungicides
43
Ben Naim, Yariv, and Yigal Cohen. "Replacing Mancozeb with Alternative Fungicides for the Control of Late Blight in Potato." Journal of Fungi 9, no. 11 (October 25, 2023): 1046. http://dx.doi.org/10.3390/jof9111046.
Full textAbstract:
Mancozeb (MZ) is a broadly used fungicide for the control of plant diseases, including late blight in potatoes caused by the oomycete Phytophthora infestans (Mont.) De Bary. MZ has been banned for agricultural use by the European Union as of January 2022 due to its hazards to humans and the environment. In a search for replacement fungicides, twenty-seven registered anti-oomycete fungicidal preparations were evaluated for their ability to mitigate the threat of this disease. Fourteen fungicides provided good control (≥75%) of late blight in potted potato and tomato plants in growth chambers. However, in Tunnel Experiment 1, only three fungicides provided effective control of P. infestans in potatoes: Cyazofamid (Ranman, a QiI inhibitor), Mandipropamid (Revus, a CAA inhibitor), and Oxathiapiprolin + Benthiavalicarb (Zorvek Endavia, an OSBP inhibitor + CAA inhibitor). In Tunnel Experiment 2, these three fungicides were applied at the recommended doses at 7-, 9-, and 21-day intervals, respectively, totaling 6, 4, and 2 sprays during the season. At 39 days post-inoculation (dpi), control efficacy increased in the following order: Zorvec Endavia > Ranman > Revus > Mancozeb. Two sprays of Zorvec Endavia were significantly more effective in controlling the blight than six sprays of Ranman or four sprays of Revus. We, therefore, recommend using these three fungicides as replacements for mancozeb for the control of late blight in potatoes. A spray program that alternates between these three fungicides may be effective in controlling the disease and also in avoiding the build-up of resistance in P. infestans to mandipropamid and oxathiapiprolin.
44
Thomas, A., D. B. Langston, and K. L. Stevenson. "Baseline Sensitivity and Cross-Resistance to Succinate-Dehydrogenase-Inhibiting and Demethylation-Inhibiting Fungicides in Didymella bryoniae." Plant Disease 96, no. 7 (July 2012): 979–84. http://dx.doi.org/10.1094/pdis-09-11-0744-re.
Full textAbstract:
Didymella bryoniae, which causes gummy stem blight (GSB) of watermelon, has a history of developing resistance to fungicides, most recently the succinate-dehydrogenase-inhibiting (SDHI) fungicide boscalid. To facilitate fungicide resistance monitoring, baseline sensitivity distributions were established for demethylation-inhibiting (DMI) fungicides tebuconazole and difenoconazole and the SDHI fungicide penthiopyrad, and reestablished for the SDHI fungicide boscalid. In all, 71 isolates with no known prior exposure to SDHIs or DMIs were used to determine the effective concentration at which mycelial growth was inhibited by 50% (EC50). EC50 values for boscalid, penthiopyrad, tebuconazole, and difenoconazole were 0.018 to 0.064, 0.015 to 0.057, 0.062 to 0.385, and 0.018 to 0.048 μg/ml, with median values of 0.032, 0.026, 0.118, and 0.031 μg/ml, respectively. Significant positive correlations between the sensitivity to penthiopyrad and boscalid (P < 0.0001, r = 0.75) and between tebuconazole and difenoconazole (P < 0.0001, r = 0.59) indicate a potential for cross-resistance between chemically related fungicides. In 2009, 103 isolates from fungicidetreated watermelon fields were tested for sensitivity to boscalid and penthiopyrad using a discriminatory concentration of 3.0 μg/ml. Of the isolates tested, 82 were insensitive and 14 were sensitive to both fungicides. Because of the significant potential for cross-resistance between closely related fungicides, growers will be advised not to use both SDHIs or both DMIs successively in the same fungicide spray program.
45
Van de Wouw, A. P., J. L. Scanlan, S. J. Marcroft, A. J. Smith, E. M. Sheedy, N. W. Perndt, C. E. Harrison, L. M. Forsyth, and A. Idnurm. "Fungicide sensitivity and resistance in the blackleg fungus, Leptosphaeria maculans, across canola growing regions in Australia." Crop and Pasture Science 72, no. 12 (2021): 994. http://dx.doi.org/10.1071/cp21369.
Full textAbstract:
Fungicide use has become a fundamental part of many crop protection systems around the world, including to control blackleg disease on canola (Brassica napus L.). In Australia, most canola growers routinely apply at least one fungicide, and potentially multiple fungicides with different modes of action, in a single growing season. There is evidence for the emergence of fungicide resistance in Leptosphaeria maculans, the causal agent of blackleg disease, to the demethylation inhibitor (DMI) class of fungicides in Australia. However, it is not known whether resistance exists towards other chemical classes such as the succinate dehydrogenase inhibitors (SDHI). In this work, 397 samples were screened for resistance towards seven fungicide treatments in stubble-borne L. maculans populations collected from eight canola-growing agro-ecological regions of Australia from 2018 to 2020, a time frame that bridges the introduction of new chemicals for blackleg control. We confirmed that DMI resistance in L. maculans is pervasive across all of the sampled canola-growing regions, with 15% of fungal populations displaying high levels (resistance scores >0.5) of resistance towards the DMI fungicides. Although resistance to newly introduced SDHI fungicides was low, we found evidence of positive cross-resistance between established DMI-only fungicides and a newly introduced combined DMI and quinone outside inhibitor fungicide, suggesting that the efficacy of the latter may be limited by widespread DMI resistance. Proactive surveillance, as performed here, may provide a means to avoid the rapid loss of fungicide efficacy in the field.
46
Ansari, TH, MT Khatun, M. Ahmed, B. Nessa, MAI Khan, MA Monsur, S. Akhter, MA Ali, and MU Salam. "Evaluation of Fungicides for the Control of Rice False Smut (Ustilaginoidea virens)." Bangladesh Rice Journal 20, no. 2 (September 29, 2017): 61–66. http://dx.doi.org/10.3329/brj.v20i2.34129.
Full textAbstract:
Outbreak of false smut, caused by the fungus Ustilaginoidea virens has been recorded in recent years in the popular rice variety BRRI dhan49 from various parts of Bangladesh. Registered and/or recommended fungicides are not yet available for chemically controlling the disease. Consequently, uses of unregistered fungicides are common by the farmers for the management of the disease. The present study was, therefore, undertaken to identify effectiveness of any fungicides to control rice false smut disease. Seven synthetic foliar fungicides were evaluated in the naturally induced diseased plots. Each fungicide was applied as spray twice, at panicle initiation and at early flowering stage. Compared to the control (no fungicide application), the fungicide Controller 300 EC reduced the hill infection by 57%, followed by Green 300 EC, Cuprofix 30 Disperss and Diazole 300 EC, each of those suppressed the hill infection by 50%. While Cuprofix 30 Disperss, compared to the control, resulted in the lowest number of infected panicle per hill, it was statistically similar to rest of the fungicides except for Confidence 10 SL. Fungicides and control did not have any significant variation on the number of infected florets per panicle. With respect to per unit (hill infection × number of infected panicle per hill) disease suppression Controller 300 EC was the best. However, none of the fungicides reached the level of the disease suppression, the essential criterion for registration and/or recommendation of a fungicide under Bangladesh conditions. It is concluded that more multi-location and multi-season experiments will be required to reach a decisive conclusion on foliar chemical options for controlling rice false smut disease under Bangladesh conditions.Bangladesh Rice j. 2016, 20(2): 61-66
47
Zhang, Yan, Randy Lamm, Christian Pillonel, Stephen Lam, and Jin-Rong Xu. "Osmoregulation and Fungicide Resistance: the Neurospora crassa os-2 Gene Encodes a HOG1 Mitogen-Activated Protein Kinase Homologue." Applied and Environmental Microbiology 68, no. 2 (February 2002): 532–38. http://dx.doi.org/10.1128/aem.68.2.532-538.2002.
Full textAbstract:
ABSTRACT Neurospora crassa osmosensitive (os) mutants are sensitive to high osmolarity and therefore are unable to grow on medium containing 4% NaCl. We found that os-2 and os-5 mutants were resistant to the phenylpyrrole fungicides fludioxonil and fenpiclonil. To understand the relationship between osmoregulation and fungicide resistance, we cloned the os-2 gene by using sib selection. os-2 encodes a putative mitogen-activated protein (MAP) kinase homologous to HOG1 and can complement the osmosensitive phenotype of a Saccharomyces cerevisiae hog1 mutant. We sequenced three os-2 alleles and found that all of them were null with either frameshift or nonsense point mutations. An os-2 gene replacement mutant also was generated and was sensitive to high osmolarity and resistant to phenylpyrrole fungicides. Conversely, os-2 mutants transformed with the wild-type os-2 gene could grow on media containing 4% NaCl and were sensitive to phenylpyrrole fungicides. Fludioxonil stimulated intracellular glycerol accumulation in wild-type strains but not in os-2 mutants. Fludioxonil also caused wild-type conidia and hyphal cells to swell and burst. These results suggest that the hyperosmotic stress response pathway of N. crassa is the target of phenylpyrrole fungicides and that fungicidal effects may result from a hyperactive os-2 MAP kinase pathway.
48
Ajayi-Oyetunde, Olutoyosi O., Carolyn J. Butts-Wilmsmeyer, and Carl A. Bradley. "Sensitivity ofRhizoctonia solanito Succinate Dehydrogenase Inhibitor and Demethylation Inhibitor Fungicides." Plant Disease 101, no. 3 (March 2017): 487–95. http://dx.doi.org/10.1094/pdis-07-16-1015-re.
Full textAbstract:
Soybean seedling diseases are caused by Rhizoctonia solani and can be managed with seed-applied fungicides that belong to different chemistry classes. To provide a benchmark for assessing a decline in sensitivities to these fungicide classes, R. solani isolates collected prior to 2001 were evaluated for their sensitivities to succinate dehydrogenase inhibitor (SDHI) (penflufen and sedaxane) and demethylation inhibitor (DMI) fungicides (ipconazole and prothioconazole). The effective concentration of each fungicide that reduced mycelial growth by 50% (EC50) was determined in vitro and compared with those of isolates recovered after 2011 from soybean plants with damping off and hypocotyl and root rot symptoms across different soybean-growing regions in the United States and Canada. All isolates, regardless of collection date, were extremely sensitive (EC50< 1 μg/ml) to the SDHI fungicides but were either extremely sensitive or moderately sensitive (1 ≤ EC50≤ 10 μg/ml) to the DMI fungicides. For all four active ingredients, variation in sensitivities was observed within and among the different anastomosis groups composing both isolate groups. Isolates collected after 2011, which also had varying in vitro sensitivities, were further evaluated for in vivo sensitivity to the four fungicides in the greenhouse. In vitro fungicide sensitivity did not always coincide with fungicide efficacy in vivo because all isolates tested, regardless of in vitro sensitivity, were effectively controlled by the application of the seed treatment fungicides in the greenhouse. Overall, our results indicate no shift in sensitivity to the fungicide classes evaluated, although considerable variability in the sensitivities of the two groups of isolates examined was present. Based on this research, continued monitoring of fungicide sensitivities of R. solani populations should occur to determine whether sensitivities become further reduced in the future.
49
N’goran, Koua Serge Beranger, Brahima Camara, Aya Carine N’guessan, Nahawa Kone, Marie-Solange Tiebre, Djakalia Ouattara, and Severin Ake. "In vitro activities of fungicides based of plants essentials oils (NECO, ASTOUN and FERCA) and phosphorous acid on Phytophthora katsurae (Pythiaceae), causal agent of the premature nut fall and the heart rot of the coconut tree, in Côte d’Iv." International Journal of Biological and Chemical Sciences 15, no. 5 (January 23, 2022): 1968–78. http://dx.doi.org/10.4314/ijbcs.v15i5.22.
Full textAbstract:
The present study aimed at evaluating the antifungal activities of NECO, ASTOUN and FERCA fungicides based of plants essentials oils against Phytophthora katsurae a major constraint in coconut plantations in Côte d'Ivoire. In vitro, the inhibition properties of these fungicides was evaluated at different concentrations 50, 100, 250, 500, 1000, 1500, 2000 and 2500 ppm and compared to a synthetic fungicide (phosphorous acid) at 1, 5, 10, 25, 50, 100 and 150 ppm on the radial growth of the mycelium of an isolated pathogen from a diseased nut. The mycelial growth was measured every day during 10 days in the Petri dishes. The results showed inhibition rates ranging from 1.48% to 100%. The biopesticides NECO and ASTOUN were effective against Phytophthora katsurae at respectively 149.14 and 272.38 ppm compared to phosphorous acid. NECO was fungitoxic at 2500 ppm and fungistatic at 1500 and 2000 ppm. Phosphorous acid was simply fungicidal at 150 ppm. Based on these results, these fungicides based of plants essentials oils could be used as biological control of Pnhytophthora katsurae in coconut plantations in Côte d'Ivoire.
50
De Souza, Hugo Manoel, Alfredo Ricieri Dias, Gustavo De Faria Theodoro, Christian Rones Wruck de Souza Osório, and Fernando Fagner Magalhães. "Cultivar, Plant Height and Fungicide for Integrated Control of Ramularia Spot and Increased Cotton Yield." Journal of Agricultural Studies 8, no. 2 (March 2, 2020): 224. http://dx.doi.org/10.5296/jas.v8i2.15871.
Full textAbstract:
Cotton is a crop with a high economic value, usually sprayed with large amounts of pesticides to control pests and diseases. Ramularia spot is a foliar disease that cause early defoliation and can compromise cotton yield; however, there is a need of information about the interaction of cultivars and plant height as a tool to improve ramularia control and increase yield. The objective of this study was to evaluate the effects of the interaction between plant height, cultivar, and fungicides applied to the severity of the leaf spot and cotton yield. The experiment was carried on during the 2014/15 crop season in Chapadão do Sul, MS, Brazil. A randomized complete block design in a 2 × 3 × 3 factorial scheme was used, where the factors were plant heights (1 and 1.5 m), cultivar (FMT 701, FM 975, and FM 944) and type of fungicide (Negative control , FT1, and FT2). The fungicidal treatments consisted of sequential sprays of different fungicides, including the triazole, strobilurin, and carboxamide groups, recommended to farmers. The cultivar FM 975 showed greater ramularia spot progress curve when grown at 1 m height and without fungicide spray. The fungicides were efficient in reducing the severity of the ramularia spot and their use in shorter plants (1 m) increased yield. The cultivar FM 975 had the highest total yield.