To see the other types of publications on this topic, follow the link: Three Fungicides.
Journal articles on the topic 'Three 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 'Three 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
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.
2
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.
3
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.
4
Mayton, H., G. A. Forbes, E. S. G. Mizubuti, and W. E. Fry. "The Roles of Three Fungicides in the Epidemiology of Potato Late Blight." Plant Disease 85, no. 9 (September 2001): 1006–12. http://dx.doi.org/10.1094/pdis.2001.85.9.1006.
Full textAbstract:
Three fungicides were tested in the field for efficacy on late blight caused by Phytophthora infestans. The effects of these fungicides on epidemic development, lesion growth rate and sporulation were measured. No fungicide completely arrested epidemic development under the environmental conditions of these experiments. However, the fungicide mixture, propamocarb hydrochloride plus chlorothalonil, had the most suppressive effect of the fungicides tested. The mechanism of effect included suppression of disease progress and lesion expansion. Growth chamber studies demonstrated that 24°C compared to 10 or 16°C limited cymoxanil efficacy.
5
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.
6
Barro, Jhonatan Paulo, Cesar Tiago Forte, Diego Trentin, Maurício Scariot, and Paola Mendes Milanesi. "Effectiveness of different fungicide formulations and number of applications in controlling wheat leaf rust." Summa Phytopathologica 43, no. 4 (December 2017): 276–80. http://dx.doi.org/10.1590/0100-5405/174240.
Full textAbstract:
ABSTRACT Leaf rust (Puccinia triticina) is one of the most common diseases in wheat crops. For effective control of such disease, leaf application of mixtures of triazole and strobilurin fungicides is recommended. The aim of this study was to evaluate the efficacy of different fungicide formulations and numbers of applications in controlling wheat leaf rust in the cultivar TBIO Pioneiro 2010. Experimental design was completely randomized, 2x2 factorial arrangement, consisting of two fungicide formulations and two numbers of applications, as well as four replicates. Treatments were: azoxystrobin + tebuconazole, three and four applications; trifloxystrobin + prothioconazole, three and four applications; and a control treatment without fungicide application. For treatments with three applications, fungicides were applied at the phenological stages of: elongation, booting and flowering. For treatments with four applications, fungicides were applied at the phenological stages of: tillering, elongation, booting and flowering. The efficiency of fungicides on leaf rust control was analyzed based on the disease severity assessment by calculating the Area Under Disease Progress Curve (AUDPC). Severity data were obtained based on percentage scores of leaf area with visible disease symptoms/signs according to Cobb’s diagrammatic scale. Fungicides with azoxystrobin + tebuconazole and trifloxystrobin + prothioconazole showed efficient control of wheat leaf rust (higher than 85%). For yield components, there was no statistical difference between numbers of applications, but there was a statistical difference between fungicide formulations, except for grain yield. Furthermore, for yield components, all fungicide treatments significantly differed from control.
7
Franke, M. D., T. B. Brenneman, and K. L. Stevenson. "Stem Rot of Peanut: Relationship Between in Vitro Fungicide Sensitivity and Field Efficacy of Fungicides." Peanut Science 25, no. 2 (July 1, 1998): 76–80. http://dx.doi.org/10.3146/i0095-3679-25-2-4.
Full textAbstract:
Abstract Isolates of Sclerotium rolfsii exhibiting varying degrees of in vitro fungicide sensitivity were exposed to fungicides in field microplots in 1995 and 1996. Individual peanut (Arachis hypogaea L.) plants in 0.9-m microplots were inoculated with isolates of S. rolfsii collected from peanut fields throughout Georgia. The 60 isolates used in the study represented the full range of sensitivity to the fungicides tebuconazole, flutolanil, and PCNB. After inoculation, microplots were treated with recommended rates of tebuconazole (0.227 kg ai/ha), flutolanil (0.337 kg ai/ha), PCNB (5.6 kg ai/ha), or were left untreated. Disease ratings were made at harvest, and pod yield from each plant was recorded. In both years, disease severity was significantly lower in treated microplots for all three fungicides. Isolates with lower in vitro fungicide sensitivity responded as well to labeled rates of all three fungicides as those with high in vitro sensitivity. In vitro sensitivity and percent control in treated microplots were not correlated for all three fungicides. Fungicide sensitivity and the level of infection in nontreated microplots also were not correlated for flutolanil and tebuconazole indicating that virulence was not affected by fungicide sensitivity. However, there was a negative correlation between in vitro sensitivity to PCNB and the level of infection in nontreated microplots in 1995, indicating that isolates with lower in vitro sensitivity were more virulent. However, this trend was not observed when the same isolates were evaluated in 1996. In 1995, plants in PCNB-treated microplots had a significantly higher yield than those in the nontreated microplots. In 1996, all fungicide treatments significantly enhanced yield. Because in vitro sensitivity and field efficacy were not correlated for all three fungicides, labeled rates should control stem rot in the field.
8
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.
9
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.
10
Briz-Cid, Noelia, Raquel Rial-Otero, Miguel Cámara, José Oliva, and Jesus Simal-Gandara. "Dissipation of Three Fungicides and Their Effects on Anthocyanins and Color of Monastrell Red Wines." International Journal of Molecular Sciences 20, no. 6 (March 22, 2019): 1447. http://dx.doi.org/10.3390/ijms20061447.
Full textAbstract:
The effect of fungicides on fermentation is of paramount importance to control the quality and safety of wines. In this work, the quality (enological parameters, color, phenolic content, antioxidant activity, and fungicide residues) of wines from Monastrell grapes fortified with iprovalicarb, mepanipyrim, and tetraconazole fungicides was evaluated. Along the winemaking process, initial residues of mepanipyrim and tetraconazole were removed in more than 90% while the dissipation of iprovalicarb was around 73%. Significant statistical differences were found in the presence of iprovalicarb and mepanipyrim residues, especially at the highest concentration assayed. For both fungicides, increases in the volatile acidity (between 4 and 8.6 times), the lactic acid content (between 8.6 and 20.5 times), the percentage of polymeric anthocyanins (between 1.3 and 1.7 times), and also a slight increase of the total phenolic index and the total anthocyanin content determined by spectrophotometry were observed. On the contrary, the total monomeric anthocyanins content decreased about 16.3% and 28.6% in the presence of iprovalicarb and mepanipyrim, respectively. These results could be related to a higher development of acetic acid or lactic bacteria in the presence of these fungicides. The color of the final wines was also different in comparison with the control, with a higher yellow component, color intensity, tonality, and hue angle because of pH changes in the medium. Tetraconazole fermentations had a more similar trend to the control wine, probably due to the lower concentration of this fungicide in the grape must at the initial time. No effects on the antioxidant activity was observed for any of the target fungicides. A multivariate statistical analysis was done to view the interrelationships between different variables (color and anthocyanins profile). The obtained model allowed the wines to be separated according to the fungicide treatment applied.
11
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
12
Mueller, D. S., S. N. Jeffers, and J. W. Buck. "Effect of Timing of Fungicide Applications on Development of Rusts on Daylily, Geranium, and Sunflower." Plant Disease 88, no. 6 (June 2004): 657–61. http://dx.doi.org/10.1094/pdis.2004.88.6.657.
Full textAbstract:
Integrated disease management should provide the most effective means of controlling rusts on ornamental crops over time, and fungicides are an important component of an integrated rust management program. Proper timing of fungicide applications is critical for effective disease management; however, information about application timing is lacking for rusts on ornamental crops. The objective of this study was to determine how fungicides affected rust development on daylily, geranium, and sunflower plants when applied several days before or after inoculation. Five fungicides registered for use against rusts on ornamental crops were evaluated: the strobilurin azoxystrobin; three sterol biosynthesis inhibiting fungicides—myclobutanil, propiconazole, and triadimefon; and the broad spectrum protectant chlorothalonil. All five fungicides significantly reduced lesion development by rust pathogens on daylily, geranium, and sunflower plants when these compounds were applied preventatively up to 15 days before inoculation and infection with a few exceptions (e.g., propiconazole on geranium and triadimefon on sunflower). Curative activity, which resulted from fungicide application after inoculation, was observed for the three rusts with some products (azoxystrobin on all three plants and myclobutanil, propiconazole, and triadimefon on geranium) when applied up to 7 days postinoculation. In general, fungicide efficacy with several of the products decreased as the time from application to inoculation (preventative activity) or inoculation to application (curative activity) increased.
13
Faske, Travis R., and Michael Emerson. "Multiyear Evaluation of Fungicide Efficacy and Application Timing for Control of Southern Rust in Hybrid Corn in Arkansas." Plant Disease 105, no. 4 (April 2021): 1108–14. http://dx.doi.org/10.1094/pdis-06-20-1247-re.
Full textAbstract:
The efficacy and timing of eight foliar fungicides to manage southern rust of corn (caused by Puccinia polysora Underwood) was investigated over 4 years in three field experiments. Each experiment consisted of one-, two-, or three-fungicide application timings at tassel, milk, or dent growth stages with quinone outside inhibitor (QoI), demethylation inhibitor (DMI), or QoI + DMI fungicides. Each year trace amounts of southern rust were observed in the field at tassel, except in 2018, when rust was not observed until physiological maturity. Southern rust severity on ear leaf and two leaves above the ear leaf was approximately 50, 35, 75, and 0% at dent in 2015, 2016, 2017, and 2018, respectively. Applications that contained a QoI or QoI + DMI fungicide provided greater southern rust control than DMI fungicides, with little variation within fungicide classes. Applications of QoI or QoI + DMI fungicides applied at tassel provided greater disease control (52.5%) than those applied at milk (5.8%) or dent (1.4%), and greater yield protection (40.4%) than those applied at milk (23.7%) or dent (2.6%) when final rust development was severe (>40%). When rust development increased later in the season, after milk growth stage, a trend of better disease control was observed with fungicides applied at milk (57.8%) compared with tassel (35.2%), but grain yield protection was similar, with an average yield protection of 7.4%. There was no yield benefit with fungicides applied in the absence of disease or at the dent growth stage. Southern rust was most effectively managed with QoI or QoI + DMI fungicides applied at tassel when southern rust was present and environmental conditions favored rust development.
14
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.
15
Simanjuntak, Donnarina, Rokhana Faizah, Agus Eko Prasetyo, and Agus Susanto. "THE EFFECTIVENESS OF FUNGICIDES AGAINST FUNGAL ISOLATES CARRIED BY OIL PALM SEEDS." Jurnal Penelitian Kelapa Sawit 25, no. 1 (March 21, 2018): 47–58. http://dx.doi.org/10.22302/10.22302/iopri.jur.jpks.v25i1.24.
Full textAbstract:
Oil palm seed is known to bring some pathogenic microbes and reduce the quality of seeds. Research aims to determine the effectiveness of fungicide active ingredients and later as a recommendation fungicide to control fungal isolates carried by oil palm seeds. Research were conducted in the Plant Protection laboratory, IOPRI business unit of Marihat, from April to October 2016. Research using descriptive analysis of seeds and seed health testing methods used consisted of visual observation of seeds and washing test. Seeds obtained from six production sites namely derpericarping, seed selection, first immersion, first winding, germination chamber, and distribution of germinated seed. The fungicides used consist of 39 different types of active ingredients. From the results of seed health testing there are three fungi carried by seeds that have been isolated, ie Aspergillus, Penicillium, and Mucor. These three fungi were further tested against 39 types of fungicides and the result there are 13 to 18 of fungicides that are effective to suppress the growth rate of the three fungi until the seventh day after the application.
16
Simanjuntak, Donnarina, Rokhana Faizah, Agus Eko Prasetyo, and Agus Susanto. "THE EFFECTIVENESS OF FUNGICIDES AGAINST FUNGAL ISOLATES CARRIED BY OIL PALM SEEDS." Jurnal Penelitian Kelapa Sawit 25, no. 1 (April 1, 2017): 47–58. http://dx.doi.org/10.22302/iopri.jur.jpks.v25i1.24.
Full textAbstract:
Oil palm seed is known to bring some pathogenic microbes and reduce the quality of seeds. Research aims to determine the effectiveness of fungicide active ingredients and later as a recommendation fungicide to control fungal isolates carried by oil palm seeds. Research were conducted in the Plant Protection laboratory, IOPRI business unit of Marihat, from April to October 2016. Research using descriptive analysis of seeds and seed health testing methods used consisted of visual observation of seeds and washing test. Seeds obtained from six production sites namely derpericarping, seed selection, first immersion, first winding, germination chamber, and distribution of germinated seed. The fungicides used consist of 39 different types of active ingredients. From the results of seed health testing there are three fungi carried by seeds that have been isolated, ie Aspergillus, Penicillium, and Mucor. These three fungi were further tested against 39 types of fungicides and the result there are 13 to 18 of fungicides that are effective to suppress the growth rate of the three fungi until the seventh day after the application.
17
Biango-Daniels, Megan N., Katrin M. Ayer, Kerik D. Cox, and Kathie T. Hodge. "Paecilomyces niveus: Pathogenicity in the Orchard and Sensitivity to Three Fungicides." Plant Disease 103, no. 1 (January 2019): 125–31. http://dx.doi.org/10.1094/pdis-04-18-0695-re.
Full textAbstract:
Paecilomyces rot of apples is a postharvest disease caused by the thermotolerant fungus Paecilomyces niveus (Byssochlamys nivea). The etiology of disease and the activity of fungicides against P. niveus are not yet well understood. This study evaluated the ability of P. niveus to infect ‘Gala’ apples growing in a conventionally managed orchard. In addition, the sensitivity of P. niveus isolates to postharvest fungicides difenoconazole, fludioxonil, and pyrimethanil was characterized for isolates from both agricultural and nonagricultural environments. Apples were wounded and mock-inoculated or inoculated with P. niveus in early July. At the time of harvest, 8 weeks after wounding, the inoculated apples had significantly larger lesions than mock-inoculated apples (P < 0.005). The average diameter of lesions on wound-inoculated apples was 11.17 mm ± 6.82 SD, while the average diameter of mock-inoculated lesions was 3.34 mm ± 1.85 SD. Disease symptoms in the orchard were similar to postharvest symptoms of Paecilomyces rot. Symptoms included a brown, flattened, circular lesion with faint concentric rings. The necrosis of mesocarp was firm and roughly U-shaped. Baseline isolates of P. niveus, from nonagricultural environments, were used to determine the effective fungicide dose at which growth was inhibited by 50% (EC50). Furthermore, fungicide sensitivity of P. niveus isolates was examined using relative growth assays at the mean baseline EC50 values to compare baseline isolates with isolates obtained from commercial apple orchards where they were likely exposed to fungicides. Among the exposed isolates, reduced sensitivity to all fungicides was observed, but significant differences between baseline and exposed isolates were only observed with fludioxonil (P < 0.0001). This is the first report demonstrating that P. niveus can infect apples that are wound-inoculated in the orchard and that isolates from agricultural environments are less sensitive to common fungicides, especially fludioxonil. This finding may have implications for the control of this postharvest diseases. Whether natural infections of apples by P. niveus is initiated in the orchard or during postharvest has yet to be determined.
18
Wade, Andrea, Chia-Hua Lin, Colin Kurkul, Erzsébet Ravasz Regan, and Reed M. Johnson. "Combined Toxicity of Insecticides and Fungicides Applied to California Almond Orchards to Honey Bee Larvae and Adults." Insects 10, no. 1 (January 8, 2019): 20. http://dx.doi.org/10.3390/insects10010020.
Full textAbstract:
Beekeepers providing pollination services for California almond orchards have reported observing dead or malformed brood during and immediately after almond bloom—effects that they attribute to pesticide exposure. The objective of this study was to test commonly used insecticides and fungicides during almond bloom on honey bee larval development in a laboratory bioassay. In vitro rearing of worker honey bee larvae was performed to test the effect of three insecticides (chlorantraniliprole, diflubenzuron, and methoxyfenozide) and three fungicides (propiconazole, iprodione, and a mixture of boscalid-pyraclostrobin), applied alone or in insecticide-fungicide combinations, on larval development. Young worker larvae were fed diets contaminated with active ingredients at concentration ratios simulating a tank-mix at the maximum label rate. Overall, larvae receiving insecticide and insecticide-fungicide combinations were less likely to survive to adulthood when compared to the control or fungicide-only treatments. The insecticide chlorantraniliprole increased larval mortality when combined with the fungicides propiconazole or iprodione, but not alone; the chlorantraniliprole-propiconazole combination was also found to be highly toxic to adult workers treated topically. Diflubenzuron generally increased larval mortality, but no synergistic effect was observed when combined with fungicides. Neither methoxyfenozide nor any methoxyfenozide-fungicide combination increased mortality. Exposure to insecticides applied during almond bloom has the potential to harm honey bees and this effect may, in certain instances, be more damaging when insecticides are applied in combination with fungicides.
19
Salman, Mazen, Mohammad Jawabreh, and Basima Abu Rumaileh. "The effect of local fungicides on conidial germination of Spilocaea oleagina in Palestine." مجلة جامعة فلسطين التقنية خضوري للأبحاث 2, no. 1 (February 9, 2014): 26–28. http://dx.doi.org/10.53671/ptukrj.v2i1.25.
Full textAbstract:
Olive leaf spot (OLS) disease or peacock disease is caused by the fungus Spilocaea oleagina, it is the most destructive disease on olive trees in most regions of Palestine. The disease is controlled by application of copper containing fungicides. Currently, there are more than 20 different fungicides sold in the Palestinian market. The efficacy of these fungicides was not tested on OLS in Palestine. The aim of this work was to test the efficacy of three major fungicides used against the disease. Fungicide solutions containing Fungran, Copper Antracol, and Kocide®101 were prepared by dissolving 0.5 g of each in 200 ml distilled water (DW) according to manufacturer instruction. Five leaves infected with OLS were soaked in each solution for 30 min. Control leaves were placed in 200 ml DW. Leaves were then placed in 9 cm petri dishes containing 3 ml DW to provide high humidity (> 85%). Each day, one leaf was removed, washed in DW and cut into one-cm2 pieces. Leaf pieces holding OLS conidia were printed on olive leaf extract agar media. Results showed that after 24h of fungicide treatment, Kocide®101 was the most effective fungicide followed by Copper Antracol and Fungran with percent conidial germination 2.08, 2.9 and 25.5%, respectively. Interestingly, Fungran efficacy after 48h (2.8% germination) was higher but not significantly different than Kocide®101 and Copper Antracol. This study showed that the efficacy of the three commonly used fungicides against OLS disease in Palestine diminished after four days of treatment. Further studies are needed to test the efficacy of these fungicides under field conditions for a better control planning of peacock disease in Palestine.
20
Salman, Mazen, Mohammad Jawabreh, and Basima Abu Rumaileh. "The effect of local fungicides on conidial germination of Spilocaea oleagina in Palestine." مجلة جامعة فلسطين التقنية للأبحاث 2, no. 1 (February 9, 2014): 26–28. http://dx.doi.org/10.53671/pturj.v2i1.25.
Full textAbstract:
Olive leaf spot (OLS) disease or peacock disease is caused by the fungus Spilocaea oleagina, it is the most destructive disease on olive trees in most regions of Palestine. The disease is controlled by application of copper containing fungicides. Currently, there are more than 20 different fungicides sold in the Palestinian market. The efficacy of these fungicides was not tested on OLS in Palestine. The aim of this work was to test the efficacy of three major fungicides used against the disease. Fungicide solutions containing Fungran, Copper Antracol, and Kocide®101 were prepared by dissolving 0.5 g of each in 200 ml distilled water (DW) according to manufacturer instruction. Five leaves infected with OLS were soaked in each solution for 30 min. Control leaves were placed in 200 ml DW. Leaves were then placed in 9 cm petri dishes containing 3 ml DW to provide high humidity (> 85%). Each day, one leaf was removed, washed in DW and cut into one-cm2 pieces. Leaf pieces holding OLS conidia were printed on olive leaf extract agar media. Results showed that after 24h of fungicide treatment, Kocide®101 was the most effective fungicide followed by Copper Antracol and Fungran with percent conidial germination 2.08, 2.9 and 25.5%, respectively. Interestingly, Fungran efficacy after 48h (2.8% germination) was higher but not significantly different than Kocide®101 and Copper Antracol. This study showed that the efficacy of the three commonly used fungicides against OLS disease in Palestine diminished after four days of treatment. Further studies are needed to test the efficacy of these fungicides under field conditions for a better control planning of peacock disease in Palestine.
21
Franke, M. D., T. B. Brenneman, K. L. Stevenson, and G. B. Padgett. "Sensitivity of Isolates of Sclerotium rolfsii from Peanut in Georgia to Selected Fungicides." Plant Disease 82, no. 5 (May 1998): 578–83. http://dx.doi.org/10.1094/pdis.1998.82.5.578.
Full textAbstract:
The fungicide sensitivity of more than 450 isolates of Sclerotium rolfsii from 11 different peanut fields in Georgia was determined based on percent inhibition of mycelial growth on agar amended with tebuconazole, flutolanil, or PCNB. The 11 locations represented a wide geographic distribution and variety of exposure histories to tebuconazole, flutolanil, and PCNB. Most of the populations sampled were significantly more sensitive than the populations that had the longest exposure to the fungicides. Of the three fungicides tested, tebuconazole and flutolanil demonstrated the strongest positive correlation in 1994 and 1995. The differences in sensitivity among locations suggest that fungicide sensitivity among S. rolfsii populations varies across Georgia. The location with the longest exposure history had the lowest sensitivity to all three fungicides.
22
Mena, Héctor, Francia Fuenmayor, José Tejera, Rafael Jiménez, and Eudis Georges. "Combate del rocío azucarado (Sphacelia sorghi McRae) del sorgo (Sorghum bicolor (L.) Moench) con funguicidas." Agronomía Mesoamericana 12, no. 2 (July 1, 2006): 205. http://dx.doi.org/10.15517/am.v12i2.17235.
Full textAbstract:
The experiment was conducted in Centro Nacional de Investigaciones in Maracay, Aragua, Venezuela. The goal of this job was determining the efficacy of some fungicides in controlling sorghum honeydew (Sphacelia sorghi McRae). A completely block randomized with four replications was used. Three systemic triazol fungicides were used and two non triazoles were included. Each dose was subdivided in three applications: 1/4 applied at panicle pre-emergence, 1/2 applied at 50 % flowering time and 1/4 applied at postflowering time, in order to cover the whole flowering period. The variables were: incidence or infected panicles per plot, panicle infection and the total infection/ plot. According to the results there was an overall good fungicide control. There was a group constituted by Tilt and Propizole, which gave the best fungus control with 96.96 and 96.55% of effectivity in controlling of panicles’ infection and a second group was integrated by Anvil, Benlate and Plantvax which made adequate control with no significant differences among them. In conclusion, the best fungicides were Tilt and Propizole. Benlate and Plantvax gave an adequate control but they are recommended under low inoculum pressure in order to avoid resistence and for economic reasons. Anvil showed 90.43% control; however, this fungicide has low relative efficacy when it is compared with other triazol fungicides.
23
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.
24
Błaszkowski, Janusz. "Bffects of foliar fungicides on the mycoflora of glumes of Triticum aestivum." Acta Mycologica 30, no. 1 (August 20, 2014): 41–48. http://dx.doi.org/10.5586/am.1995.004.
Full textAbstract:
In the years 1983-1984. the effect of three foliar fungicides, i.e.. Bayleton 25 WP. Dithane M-45 and Funaben K on the mycoflora associated with glumus of spring <i>Tritieum aestivum</i> cv. Kolibri cultivated in the field was investigated. During each vegetative period, glumes were collected in the milky ripe of seeds. Fungi species associated with glumes were determined based of colonies isolated from glumes incubated in Petri dishes with potato glucose agar. The fungicide which reduced the most the overall number of fungal isolates was Bayleton 25 WP. The number of species was most reduced following Dithane M-45 application. The mycoflora of glumes which had been untreated and treated with fungicides was compared with fungicides-treated and fungicide-untreated seeds and leaves. The highest similarity in the mycoflora of fungicide-untreated plant parts was found when glumes and seeds were compared. The mycoflora of fungicide-treated glumes, leaves, and seeds varied. depending on the year and fungicide applied.
25
Geml, József, Donald D. Davis, and David M. Geiser. "Influence of Selected Fungicides on in vitro Growth of Artillery Fungi (Sphaerobolus spp.)." Journal of Environmental Horticulture 23, no. 2 (June 1, 2005): 63–66. http://dx.doi.org/10.24266/0738-2898-23.2.63.
Full textAbstract:
Abstract We tested the inhibitory effect of 14 fungicides, 13 of which were known to be effective against the basidiomycete Agaricus, at 5 and 20 ppm on the in vitro growth of three species of artillery fungi: Sphaerobolus iowensis, S. stellatus, and a previously undescribed Sphaerobolus sp. Captafol, epoxiconazole, thiophanate-methyl, triflumizole, and triphenyltin acetate were the most effective inhibitors against all three Sphaerobolus species, and the reduction in growth was directly related to fungicide concentration. Chloroneb, chlorothalonil/zinc oxide, fuberidazole, glyodin, and tolylfluanid showed varying results, depending on fungal species and fungicide concentration; however, they were much less effective than the previous five fungicides. Dazomet, dinocap, folpet, and ferbam failed to slow the growth of any artillery fungi at either concentration. This preliminary study revealed that certain fungicides suppress growth of artillery fungi and should be further tested in the field.
26
Rashid, M. H., M. Ashraf Hossain, M. A. Kashem, Shiv Kumar, M. Y. Rafii, and M. A. Latif. "Efficacy of Combined Formulations of Fungicides with Different Modes of Action in Controlling Botrytis Gray Mold Disease in Chickpea." Scientific World Journal 2014 (2014): 1–6. http://dx.doi.org/10.1155/2014/639246.
Full textAbstract:
Botrytis gray mold (BGM) caused byBotrytis cinereaPers. Ex. Fr. is an extremely devastating disease of chickpea (Cicer arietinumL.) and has a regional as well as an international perspective. Unfortunately, nonchemical methods for its control are weak and ineffective. In order to identify an effective control measure, six fungicides with different modes of action were evaluated on a BGM susceptible chickpea variety BARIchhola-1 at a high BGM incidence location (Madaripur) in Bangladesh for three years (2008, 2009, and 2010). Among the six fungicides tested, one was protectant [Vondozeb 42SC, a.i. mancozeb (0.2%)], two systemic [Bavistin 50 WP, a.i. carbendazim (0.2%), and Protaf 250EC, propiconazole (0.05%)], and three combination formulations [Acrobat MZ690, dimethomorph 9% + mancozeb 60%, (0.2%); Secure 600 WG, phenomadone + mancozeb (0.2%); and Companion, mancozeb 63% + carbendazim 12% (0.2%)]. The results showed superiority of combination formulations involving both protectant and systemic fungicides over the sole application of either fungicide separately. Among the combination fungicides, Companion was most effective, resulting in the lowest disease severity (3.33 score on 1–9 scale) and the highest increase (38%) of grain yield in chickpea. Therefore, this product could be preferred over the sole application of either solo protectant or systemic fungicides to reduce yield losses and avoid fungicide resistance.
27
Dalla Lana, Felipe, Pierce A. Paul, Claudia V. Godoy, Carlos M. Utiamada, Luís Henrique C. P. da Silva, Fabiano V. Siqueri, Carlos A. Forcelini, et al. "Meta-Analytic Modeling of the Decline in Performance of Fungicides for Managing Soybean Rust after a Decade of Use in Brazil." Plant Disease 102, no. 4 (April 2018): 807–17. http://dx.doi.org/10.1094/pdis-03-17-0408-re.
Full textAbstract:
An apparent decline of fungicide performance for the control of soybean rust in Brazil has been reported but the rate at which it has occurred has not been formally quantified. Control efficacy and yield response to three fungicides applied as single active ingredients (a.i.)—azoxystrobin (AZOX), cyproconazole (CYPR), and tebuconazole (TEBU)—and four applied as mixtures—AZOX+CYPR, picoxystrobin + CYPR, pyraclostrobin + epoxiconazole, and trifloxystrobin + prothioconazole (TRIF+PROT)—were summarized using network meta-analytic models fitted to mean severity and yield data from 250 trials (10-year period). The effect of year was tested on both variables in a meta-regression model. Overall control efficacy ranged from 56 to 84%; the three single-a.i. fungicides performed the poorest (56 to 62%). Yield increase for single-a.i. fungicides was as low as 30% but ranged from 47 to 65% for the premixes. Significant declines in both variables were detected for all fungicides except TRIF+PROT. For TEBU, control efficacy (yield response) declined the most: 78% (18%) to 54% (8%) from 2004–05 to 2013–14. The recent surge of resistant populations of Phakopsora pachyrhizi to both demethylation inhibitor and quinone outside inhibitor fungicides is likely the driving force behind a significant decline after 4 years of fungicide use.
28
Luna, Martha P. Romero, and Kiersten A. Wise. "Timing and Efficacy of Fungicide Applications for Diplodia Ear Rot Management in Corn." Plant Health Progress 16, no. 3 (January 2015): 123–31. http://dx.doi.org/10.1094/php-rs-15-0010.
Full textAbstract:
Diplodia ear rot, a corn (Zea mays L.) disease caused by the fungus Stenocarpella maydis (Berk.) B. Sutton, has been a persistent ear rot across the United States. Management options are currently limited. Field trials conducted under inoculated and non-inoculated conditions were established at two locations in Indiana from 2011 to 2013 to test the fungicides azoxystrobin plus propiconazole and prothioconazole against Diplodia ear rot. Fungicides were applied at three individual growth stages during each year. Fungicides did not consistently reduce Diplodia ear rot compared to non-fungicide-treated controls in any year. Applications also did not consistently increase yield at any timing under inoculated and non-inoculated plots compared with the non-fungicidetreated control. Fungicides were tested in an in vitro assay to determine the effective fungicide concentration at which 50% of mycelial growth or conidial germination of S. maydis was inhibited (EC50). Propiconazole and prothioconazole EC50 values indicated efficacy in reducing fungal growth under controlled conditions; however, current fungicide application methods and plant barriers to fungicide contact with the pathogen may prevent these products from effectively reducing Diplodia ear rot in a field setting. Accepted for publication 23 August 2015. Published 1 September 2015
29
Mmbaga, M. T., and R. J. Sauvé. "Management of powdery mildew in flowering dogwood in the field with biorational and conventional fungicides." Canadian Journal of Plant Science 84, no. 3 (July 1, 2004): 837–44. http://dx.doi.org/10.4141/p03-104.
Full textAbstract:
In a 2 yr study, control of powdery mildew on flowering dogwood (Cornus florida L.) by four biorational and four conventional fungicides was assessed on seedlings and on 3 yr liners in the field. Biorational fungicides applied were three household soaps containing 0.2% triclosan (Irgasan® DP 300)—Ajax® liquid hand soap, Equate® liquid dish soap and Palmolive® liquid dish soap-and potassium bicarbonate salt. Conventional fungicides applied were propiconazole, thiophanate methyl, azoxystrobin and copper sulfate pentahydrate. All products controlled powdery mildew compared with water controls. Application of the biorational fungicides on a weekly basis was as effective as propiconazole and thiophanate methyl and more effective than azoxystrobin and copper sulfate pentahydrate. Application of some biorational products at semi-monthly intervals was slightly less effective. Of the biorational fungicides, Palmolive® was the most effective but was phytotoxic, whereas Ajax®, Equate® and potassium bicarbonate were not. When three applications of any biorational fungicide were rotated with one application of propiconazole, the incidence of powdery mildew was less than when a fungicide rotation was not included. Plant growth was enhanced with either biorational or conventional fungicides compared with water controls. Propiconazole treatments resulted in the highest growth rates, whereas biorational products were as effective in promoting growth as thiophanate methyl, azoxystrobin or copper sulfate pentahydrate. The incorporation of biorational fungicides in a powdery mildew disease management program may have economic and environmental benefits because they are less costly than conventional fungicides and presumed safer to the environment and the applicators. Key words: Cornus florida L., Erysiphe (sect. Microsphaera) pulchra, Microsphaera pulchra, Oidium spp, Phyllactinia guttata
30
Krupenko*, N. A., and I. N. Odintsova. "Peculiarities of action and retrospective analysis of fungicides efficacy for protection of soft winter wheat against leaf diseases." PLANT PROTECTION NEWS 103, no. 4 (December 25, 2020): 224–32. http://dx.doi.org/10.31993/2308-6459-2020-103-4-13741.
Full textAbstract:
The data on the efficacy of 40 fungicides for protection of soft winter wheat against leaf diseases during 2010–2019 are demonstrated. Biological efficacy is calculated based upon the area under the curve of disease development. Biological and economical efficacy of those compounds has been analyzed depending on the number of components, as well as chemical classes of active agents in those compounds. The highest biological efficacy of one-component fungicides against powdery mildew has been recorded for those containing proquinazid, tebuconazole and metrafenone – 69.9–79.3 %. Among 23 two-component fungicides the higher efficacy (82.1–84.3 %) against powdery mildew has been recorded for the fungicides containing azole combined with morpholine. Biological efficacy against Septoria leaf blotch has varied from 64.7 to 88.0 % depending on fungicide composition. Among three-component fungicides the efficacy against powdery mildew has varied from 59.5 to 82.8 %, and against Septoria leaf blotch it has varied from 59.8 to 89.9 %. As a result of the diseases severity decrease due to the fungicide application the saved yield has reached 9.9 centner of grain per hectare.
31
Moyer, Michelle M., Jensena M. Newhouse, and Gary G. Grove. "Efficacy of Biopesticides and Leaf Removal in Grapevine Powdery Mildew Management." Plant Health Progress 17, no. 2 (January 2016): 84–91. http://dx.doi.org/10.1094/php-rs-16-0009.
Full textAbstract:
Integrating biological-based fungicides into conventional spray programs may help with fungicide resistance management. However, little is known about how to best integrate these products while still maintaining maximum disease control. Programs with as few as one synthetic fungicide or as many as three synthetic fungicides added to a biopesticide-based rotation during the bloom period of Vitis vinifera had significantly better disease control than a biopesticide-only-based program. When integrated with different timings of fruit-zone leaf removal, specific combinations of biopesticide programs and fruit-zone leaf removal enhanced the efficacy of that program to be on par with disease control seen in a program entirely based on synthetic fungicides. This suggests that when designing a fungicide program using biopesticides as a base, the addition of a synthetic fungicide during the window of ontogenic susceptibility in clusters and the adoption of cultural practices such as leaf removal can significantly improve the efficacy of that program. Accepted for publication 11 April 2016. Published 20 April 2016.
32
Hooker, David C., Nader Soltani, and Peter H. Sikkema. "Response of winter wheat to herbicide plus fungicide plus ammonium thiosulphate tank-mixes." Canadian Journal of Plant Science 98, no. 6 (December 1, 2018): 1357–64. http://dx.doi.org/10.1139/cjps-2017-0359.
Full textAbstract:
A study was conducted at six field sites near Exeter and Ridgetown, ON, over a 3 yr period (2014, 2015, and 2016) to determine the effect of ammonium thiosulphate (ATS), various fungicides (azoxystrobin/propiconazole, trifloxystrobin/prothioconazole, or pyraclostrobin/metconazole), and various herbicides (bromoxynil/MCPA, thifensulfuron/tribenuron + MCPA, pyrasulfotole/bromoxynil, or 2,4-D/dichlorprop) applied alone and in tank-mix combinations on winter wheat crop injury and grain yield. The treatments were applied using Hypro ULD120-02 flat-fan nozzles around Zadoks growth stage 30. The herbicides and fungicides caused <0.6% leaf injury when ATS was not added to the tank-mix. When averaged across fungicides in ATS tank-mixes, leaf injury 1 wk after treatment application was 3.5% to 3.7% with thifensulfuron/tribenuron and dichlorprop-P/2,4-D herbicides and 5.1% to 5.8% injury with bromoxynil/MCPA and thifensulfuron/tribenuron herbicides. On the three field sites with the highest leaf injury, a fungicide–ATS tank-mix increased injury to 4.5% averaged across fungicides and to 4.3% with a herbicide–ATS tank-mix averaged across herbicides. Three-way tank-mixes of herbicide–fungicide–ATS caused the highest injury (7.1%). Despite significant crop injury 1 WAA with some tank-mixes, there was no evidence that grain yields were adversely affected. This study shows that the co-application of a three-way tank-mix of ATS with fungicides (azoxystrobin/propiconazole, trifloxystrobin/prothioconazole, or pyraclostrobin/metconazole) and herbicides (bromoxynil/MCPA, thifensulfuron/tribenuron + MCPA, pyrasulfotole/bromoxynil, or dichlorprop-P/2,4-D) has the potential to cause considerable injury in winter wheat under some environmental conditions in Ontario, but the effect seems transient, with no grain yield reductions detected.
33
Grove, G. G., R. J. Boal, and L. H. Bennett. "Managing Powdery Mildew of Cherry in Washington Orchards and Nurseries with Spray Oils." Plant Health Progress 1, no. 1 (January 2000): 2. http://dx.doi.org/10.1094/php-2000-0728-01-rs.
Full textAbstract:
Powdery mildew of sweet cherry is the most serious disease in irrigated orchards and nurseries of Washington. The fungus infects foliage and fruit, but fruit infections are of primary concern due to the potential for rejection of entire crops. Development of resistance to demethylation inhibiting (DMI) fungicides in the mid-1990s increased the difficulty in controlling this disease. Orchard mildew management programs that utilize oils, DMI and strobilurin fungicides have been developed for use in eastern Washington. A growth stage (phenology)/calendar-based program provides excellent disease control, utilizes three fungicidal modes of action, and minimizes oil-induced fruit and foliar phytotoxicity by limiting oil use to no later than the pit hardening stage. A second approach that utilizes oils in a temperature-based disease forecasting system provides excellent disease control with fewer fungicide applications. Accepted for publication 19 July 2000. Published 28 July 2000.
34
Fingstag, Maiquiel Diego, Ricardo Trezzi Casa, Amauri Bogo, Paulo Kuhnem, Luis Sangoi, Juliana Borba Valente, Diego Bevilaqua, Otávio Ajala Fiorentin, and Mayra Juline Gonçalves. "Fungicide performance on Fusarium meridionale control, grain yield and grain damage in maize." Summa Phytopathologica 45, no. 3 (September 2019): 265–71. http://dx.doi.org/10.1590/0100-5405/193255.
Full textAbstract:
ABSTRACT Gibberella ear rot (GER) in maize, caused by Fusarium graminearum species complex, is a destructive disease in southern Brazil and worldwide. Five field-experiments were conducted to determine fungicide efficacy, grain yield and grain quality (study I), as well as response of increasing rates (study II) on GER control, grain yield (GY) and grain damage (GD) in maize during the 2014/15 and 2015/16 growing seasons. Fungicides were sprayed 48 h before (preventive action) or 48 h after (curative action) inoculation of two Fusarium meridionale isolates (PR and MG). Study I consisted in applying nine active ingredients (metconazole, pyraclostrobin, tebuconazole, trifloxystrobin, prothioconazole, thiophanate-methyl, azoxystrobin, cyproconazole and carbendazim) present in eight commercial formulations at two sowing dates. Study II consisted in applying increasing rates of three fungicides evaluated at three sowing dates using only PR isolate. In study I, no differences were observed among fungicides when the variables GER, GY and GD were analyzed together. There were interactions between time of fungicide application and F. meridionale isolates when GER severity and GY were considered. Preventive fungicide application at different sowing dates and the use of MG isolate reduced GER by 11.6% and increased GY by 5.3%, compared to curative application. In study II, there was a significant interaction between fungicides and application time for GER, GY and GD. Preventive application of trifloxystrobin + prothioconazole (0.15 + 0.17 and 0.22 + 0.26 L ha-1), pyraclostrobin + metconazole (0.19 + 0.12 and 0.29 + 0.18 L ha-1) and carbendazim (2 L ha-1) reduced GER by 41 and 50%, 47 and 54%, and 54% at the three sowing dates, respectively. There was an increment of 45.7% and 46.8% in GY when trifloxystrobin + prothioconazole (0.15 + 0.17 and 0.22 + 0.26 L ha-1), respectively, were preventively sprayed at the three sowing dates, compared to the control treatment. Trifloxystrobin + prothiocanazole, pyraclostrobin + metconazole and carbendazim (1.0 and 2.0 L ha-1) preventively sprayed at two rates reduced GD incidence by 53.5 and 48.7%, 47.7 and 57.5%, 48.1 and 50.5%, respectively, for each fungicide and rate, and could be incorporated into a disease management program.
35
Buck, James W., and Leon L. Burpee. "The effects of fungicides on the phylloplane yeast populations of creeping bentgrass." Canadian Journal of Microbiology 48, no. 6 (June 1, 2002): 522–29. http://dx.doi.org/10.1139/w02-050.
Full textAbstract:
The effects of fungicides on population size and the development of fungicide resistance in the phylloplane yeast flora of bentgrass was investigated. In the spring of 2001, azoxystrobin, chlorothalonil, flutolanil, and propiconazole were applied separately over a 6-week period to creeping bentgrass (Agrostis palustris Huds.). Total and fungicide-resistant yeast populations were assessed by dilution plating onto either potato dextrose agar or potato dextrose agar amended with the test fungicides. Total yeast populations in the fungicide- treated plots were significantly lower than the check plots on three out of four sample dates. In the fall, azoxystrobin or propiconazole were applied twice to the bentgrass over 3 weeks. Significantly larger total yeast populations were observed compared with resistant or highly resistant populations for each treatment on every sample date. Total yeast populations were significantly higher in the check plots compared with either the propiconazole- or azoxystrobin-treated plots on the first three of five sample dates. A collection of yeasts (N = 114) with no prior exposure to fungicides were more sensitive to chlorothalonil, propiconazole, flutolanil, and iprodione than a second group (N = 115) isolated from fungicide-treated turfgrass. These results suggest that fungicide resistance among phylloplane yeasts is widespread and could be an important factor in the development of biological control agents for turfgrass diseases.Key words: yeast, biological control, fungicide, resistance, phylloplane.
36
Shew, B. B., M. K. Beute, and J. E. Bailey. "Potential for Improved Control of Southern Stem Rot of Peanut with Resistance and Fungicides1." Peanut Science 12, no. 1 (January 1, 1985): 4–7. http://dx.doi.org/10.3146/pnut.12.1.0002.
Full textAbstract:
Abstract Potential for improved control of southern stem rot caused by Sclerotium rolfsii Sacc.on peanut (Arachis hypogaea L.) was evaluated by combining moderate resistance with fungicide use. Various fungicides including carboxin, oxycarboxin, propiconazol, OAC 3890, and PCNB were applied to peanut lines NC 8C, NC Ac 18016, and Florigiant in North Carolina during 1980, 1981, and 1982. Consistently fewer disease loci occurred on NC Ac 18016 than on NC 8C or Florigiant. At least one fungicide reduced stem rot incidence in two of three years tested, but fungicide use did not result in greater yields. Effects of disease resistance and fungicides on suppression of stem rot development were additive.
37
Saito, S., and C. L. Xiao. "Fungicide Resistance in Botrytis cinerea Populations in California and its Influence on Control of Gray Mold on Stored Mandarin Fruit." Plant Disease 102, no. 12 (December 2018): 2545–49. http://dx.doi.org/10.1094/pdis-05-18-0766-re.
Full textAbstract:
Gray mold caused by Botrytis cinerea is an emerging postharvest disease affecting stored mandarin fruit in California. To develop effective control programs, fungicide sensitivities to four citrus postharvest fungicides were determined. One hundred B. cinerea isolates each in 2015 and 2016 were obtained from decayed fruit collected within packinghouses and tested for resistance to the fungicides. Sensitivity to azoxystrobin was examined based on the point mutation in the cyt b gene using PCR, while resistance to fludioxonil, pyrimethanil, and thiabendazole was examined on fungicide-amended media. For azoxystrobin, 83 and 98% of the isolates were resistant in 2015 and 2016, respectively. For pyrimethanil, 71 and 93% were resistant in 2015 and 2016, respectively. For thiabendazole, 63 and 68% were resistant in 2015 and 2016, respectively. No fludioxonil resistance was detected in both years. Five fungicide-resistant phenotypes were detected, and the most common phenotype was triple resistance to azoxystrobin, pyrimethanil, and thiabendazole, accounting for 59 and 65% in 2015 and 2016, respectively. Of the 200 B. cinerea isolates, 5, 23.5, and 62% were resistant to one, two, or three classes of fungicides, respectively. Inoculation tests were conducted to evaluate if the fungicides at label rates controlled various resistant phenotypes on fruit. Most fungicides failed to control gray mold on mandarin fruit inoculated with the respective fungicide resistant phenotypes. Our results suggest that alternative control methods need to be integrated into existing decay control programs to target this emerging disease on mandarin fruit.
38
Keinath, Anthony P. "Integrated Management of Downy Mildew on Slicing Cucumber With Fungicides and Host Resistance But Not Trellising." Plant Disease 103, no. 10 (October 2019): 2592–98. http://dx.doi.org/10.1094/pdis-02-19-0323-re.
Full textAbstract:
The objective of this study was to evaluate fungicide applications, host resistance, and trellising, alone and in combination, as management practices for downy mildew on slicing cucumber. A split-split plot experimental design was used with three and four replications in spring and fall 2017, respectively. The whole-plot treatment was fungicide, four applications of chlorothalonil (Bravo Weather Stik 6SC) alternated with three applications of cyazofamid (Ranman 400SC), or water. Split plots were nontrellised or trellised with four strings supported by stakes. Split-split plots were cultivar Bristol, which is intermediately resistant to downy mildew, or cultivar Speedway, which is susceptible to downy mildew with similar parentage as Bristol. In both seasons, area under the disease progress curve (AUDPC) values were lower with fungicides than water for both cultivars. In the spring, AUDPC for Bristol was lower than for Speedway regardless of fungicide treatment. In the fall, Bristol had a lower AUDPC than Speedway with fungicides, but the AUDPC did not differ between the two cultivars with water. The mean AUDPC for trellised plants (376.2) was lower than for nontrellised plants (434.0; P = 0.007). Fungicide applications increased marketable and total fruit weights in both seasons (P ≤ 0.0002). Marketable weight with fungicides was almost double (93% greater) the marketable weight with water. Marketable weight was 55% greater for Bristol than for Speedway in spring, but yields did not differ between cultivars in fall (season-by-cultivar interaction, P ≤ 0.0003). Because trellising had no effect on marketable yields (P = 0.11), trellising is not recommended for managing downy mildew on slicing cucumber. Of the three management techniques examined, fungicides had the largest effects on disease and yields, followed by cultivar resistance.
39
Puig, Mireia, Concepció Moragrega, Lídia Ruz, Emilio Montesinos, and Isidre Llorente. "Controlling Brown Spot of Pear by a Synthetic Antimicrobial Peptide Under Field Conditions." Plant Disease 99, no. 12 (December 2015): 1816–22. http://dx.doi.org/10.1094/pdis-03-15-0250-re.
Full textAbstract:
Brown spot of pear, caused by Stemphylium vesicarium, is a fungal disease of increasing importance in several pear-growing areas of Europe. Disease control measures include the application of fungicides and sanitation methods. Antimicrobial peptides may be a complement or alternative to conventional fungicides used to manage brown spot disease. In a previous study, the synthetic peptide BP15 showed postinfection fungicidal activity against S. vesicarium in in vitro and detached-leaf assays. In the present study, the efficacy of BP15 (KKLFKKILKVL-NH2) in controlling brown spot of pear was evaluated under field conditions using potted plants and pear trees in orchards. In field trials, the treatments with BP15 or with the fungicide thiram were scheduled according to the infection risk predicted by the BSPcast model. Potted pear plants treated with BP15 showed a disease reduction of about 42 to 60% in five of seven trials. In three of four tree trials, the disease severity on shoots treated with BP15 was significantly lower than in the nontreated controls, with a mean efficacy of 38.2%. It was concluded that BP15 is a good candidate to be further developed as a fungicide for controlling brown spot of pear.
40
Blandón-Díaz, Jorge Ulises, Gregory A. Forbes, Jorge L. Andrade-Piedra, and Jonathan E. Yuen. "Assessing the Adequacy of the Simulation Model LATEBLIGHT Under Nicaraguan Conditions." Plant Disease 95, no. 7 (July 2011): 839–46. http://dx.doi.org/10.1094/pdis-10-10-0702.
Full textAbstract:
In this study, the adequacy of the late blight simulation model LATEBLIGHT (version LB2004) was evaluated under Nicaraguan conditions. During 2007 to 2008, five field experiments were conducted in three potato-production regions in northern Nicaragua. Two susceptible (‘Cal White’ and ‘Granola’) and one resistant (‘Jacqueline Lee’) potato cultivars were evaluated without use of fungicides and with three application intervals (4, 7, and 14 days) of the fungicide chlorothalonil. The simulation model was considered adequate because it accurately predicted high disease severity in susceptible cultivars without fungicide protection, and demonstrated a decrease in the disease progress curves with additional fungicide applications, similar to that observed in the plots. The model also generally predicted inadequate fungicide control, even with a 4-day spray interval, which also occurred in the field. Lack of adequate fungicide protection would indicate the need for cultivars with higher levels of durable resistance, and that farmers should consider more effective fungicides applications (higher dosages or different chemistries) if susceptible cultivars are used.
41
McManus, P. S., V. M. Best, R. P. Voland, and B. L. Leininger. "Sensitivity of Monilinia oxycocci to Fenbuconazole and Propiconazole in vitro and Control of Cranberry Cottonball in the Field." Plant Disease 83, no. 5 (May 1999): 445–50. http://dx.doi.org/10.1094/pdis.1999.83.5.445.
Full textAbstract:
The efficacy of fungicides in controlling cottonball disease of cranberry was tested during 1996 to 1998 at three locations in Wisconsin. For some fungicides, the efficacy of four applications, two each during shoot elongation and bloom, was compared with two applications during bloom only. Spraying twice during bloom was as effective in controlling secondary infection as spraying twice during shoot elongation plus twice during bloom. Azoxystrobin, cyprodinil, and propiconazole were equally effective. None of the treatments affected yield, fruit retention, or berry weight compared with the controls. Sensitivity of M. oxycocci, the cottonball pathogen, to fenbuconazole and propiconazole was tested in vitro by comparing the distributions of ED50 values of populations collected from three sites that differed in previous exposure to fungicides. Median ED50 values for fenbuconazole were significantly greater at sites where sterol demethylation inhibitor fungicides had been used compared with a site where fungicides had never been used, but median ED50 values for propiconazole did not differ among sites. There was no correlation between the sensitivities to fenbuconazole and propiconazole. The data will form the basis of recommendations aimed at delaying the onset of fungicide resistance and will provide a baseline for monitoring resistance to fenbuconazole and propiconazole in populations of M. oxycocci in the future.
42
Robinson, Melody A., Michael J. Cowbrough, Peter H. Sikkema, and François J. Tardif. "Winter wheat (Triticum aestivum L.) tolerance to mixtures of herbicides and fungicides applied at different timings." Canadian Journal of Plant Science 93, no. 3 (May 2013): 491–501. http://dx.doi.org/10.4141/cjps2012-181.
Full textAbstract:
Robinson, M. A., Cowbrough, M. J., Sikkema, P. H. and Tardif, F. J. 2013. Winter wheat (Triticum aestivum L.) tolerance to mixtures of herbicides and fungicides applied at different timings. Can. J. Plant Sci. 93: 491–501. Farmers commonly tank-mix herbicides and fungicides to reduce application costs. In the spring of 2008, there were reports of winter wheat injury with the application of herbicide–fungicide tank-mixes early in the growing season. This study was established to determine the tolerance of winter wheat to herbicide–fungicide mixtures as influenced by time of application. Field studies were conducted at four Ontario locations in 2009 and 2010 with three herbicides and four fungicides. Herbicide–fungicide tank-mixes were applied early, under cold conditions, and late at growth stage Zadoks 37–39. Dichlorprop/2,4-D mixed with tebuconazole caused up to 15% injury when applied early and up to 29% injury when applied late. Bromoxynil/MPCA mixed with tebuconazole injured wheat up to 15% when applied early but only 10% when applied late. Other herbicide and fungicide mixes caused a lower level of injury. Visible injury was transient and did not reduce winter wheat yields. The likelihood of tank-mixes causing injury was greater when they were applied late. The fungicide tebuconazole caused the highest level of injury when mixed with herbicides and injury was particularly high with dichlorprop/2,4-D.
43
Rosenzweig, N., L. E. Hanson, S. Mambetova, Q. W. Jiang, C. Guza, J. Stewart, and P. Somohano. "Fungicide Sensitivity Monitoring of Alternaria spp. Causing Leaf Spot of Sugarbeet (Beta vulgaris) in the Upper Great Lakes." Plant Disease 103, no. 9 (September 2019): 2263–70. http://dx.doi.org/10.1094/pdis-12-18-2282-re.
Full textAbstract:
Alternaria leaf spot (ALS), caused by Alternaria spp., can occur wherever sugarbeet is grown. Infection by Alternaria spp. and disease management has historically been considered a minor issue in sugarbeet production in the United States. An increase of both incidence and severity in 2016 of ALS high enough to cause yield loss has been observed in Michigan. With a renewed need to consider potential management of this disease, the sensitivity was determined for populations of Alternaria spp. to three classes of fungicides currently labeled for management of leaf spot on sugarbeet, including demethylase inhibitor (DMI), quinone outside inhibitor (QoI), and organo-tin fungicides. Leaves with symptoms of ALS were sampled from sugarbeet fields in east-central Michigan and southwestern Ontario, Canada. Monoconidial isolates were obtained to determine sensitivity to each fungicide class above. A spiral gradient dilution method was used to estimate the fungicide effective concentration (in milligrams per liter) that caused a 50% inhibition of fungal growth in vitro for all isolates. Significant temporal shifts were detected in the frequencies of sensitivity phenotypes to DMI and QoI but not organo-tin fungicides from 2016 through 2017. Individual isolates of Alternaria spp. were recovered with cross-resistance to DMI and multiple resistance to DMI, QoI, and triphenyltin hydroxide fungicides. To our knowledge, this is the first report of a fungus other than Cercospora beticola with resistance to organo-tin fungicides. Fungicide sensitivity monitoring indicates that an effective integrated disease management approach combining fungicide efficacy trials and monitoring pathogen biology is essential for developing effective resistance management recommendations.
44
LAHLALI, Rachid, Alieu MOININA, Said EZRARI, Dustin MACLEAN, and Mohammed BOULIF. "Apple Scab Disease Severity in the Sais Region of Morocco and its Sensitivity to Three Commercial Fungicides." Notulae Scientia Biologicae 11, no. 2 (June 28, 2019): 249–57. http://dx.doi.org/10.15835/nsb11210434.
Full textAbstract:
Apple scab, Venturia inaequalis (Cooke) G. Winter, results in numerous fungicide applications in the Sais region of Morocco. We conducted the study to determine the susceptibility of cultivars through field survey and to evaluate the sensitivity of V. inaequalis to three fungicides using both in vitro and in vivo methods. We surveyed 100 apple orchards and collected two samples. Disease survey showed that the cultivars were highly susceptible to apple scab (grand mean of leaf scab: Golden Delicious, 40.31%; Starking Delicious, 20.45%; and Gala, 18.92%). Results underlined no significant differences between isolates in term of inhibition rate of mycelial growth and averaged disease severity. However, both treatment and concentration were statistically significant. EC50 values ranged from 2.33 µg/ml to 7.40 µg/ml and resistance factor (RF) values of 0.55, 1.02 and 1.79 were obtained for difenoconazole, trifloxystrobin and thiophanate-methyl, respectively. In vivo tests at a concentration of 10 µg/ml on the isolate ViIF using a curative method showed a high efficacy of trifloxystrobin (96.38%), and low efficacy of thiophanate-methyl (29.65%) and difenoconazole (24.62%). V. inaequalis was most sensitive to trifloxystrobin followed by difenoconazole and thiophanate-methyl, respectively. From this work, it was recommended testing more isolates and contact fungicides in order to develop a baseline sensitivity of the pathogen population against commonly used fungicides to treat the disease, as continued usage over time and the introduction of new fungal races may result in a decrease in fungicide efficacy.
45
Khan, M. F. R., and A. L. Carlson. "Effect of Fungicides on Sugar Beet Yield, Quality, and Postharvest Respiration Rates in the Absence of Disease." Plant Health Progress 10, no. 1 (January 2009): 5. http://dx.doi.org/10.1094/php-2009-1019-01-rs.
Full textAbstract:
Five fungicides were each applied on sugar beet (Beta vulgaris) three times at about 14-day intervals beginning in July in 2005 through 2008. No foliar disease occurred in the nontreated control or any fungicide treatment. There were no significant differences in root yield, recoverable sucrose, or sucrose concentration among treatments. In 2007 and 2008, postharvest storage respiration rates were determined after 30 and 90 days in storage. There was no significant difference in respiration rates among treatments. There was no apparent benefit in applying these fungicides in seasons when no foliar disease developed. Accepted for publication 7 September 2009. Published 19 October 2009.
46
LaMondia, J. A. "Actigard Increases Fungicide Efficacy Against Tobacco Blue Mold." Plant Disease 92, no. 10 (October 2008): 1463–67. http://dx.doi.org/10.1094/pdis-92-10-1463.
Full textAbstract:
Blue mold, caused by Peronospora tabacina, can be economically damaging to cigar wrapper tobacco (Nicotiana tabacum). We evaluated acibenzolar-S-methyl (ASM) as Actigard 50WG alone and in combination with a standard fungicide program for efficacy against blue mold on shade-grown cigar wrapper tobacco in Windsor, CT. The standard fungicide program consisted of dimethomorph (Acrobat MZ or Forum) plus mancozeb (Dithane), alternated with azoxystrobin (Quadris), and applied at label rates on six occasions at 14-day intervals. Treated and untreated 5-by-5-m plots were replicated four times in 2003, 2004, 2005, 2006, and 2007. ASM treatments were applied alone or in combination with fungicides at the third, fourth, and fifth spray dates at rates ranging from 1.1 to 17.5 g a.i./ha. Disease was greatest in nontreated plots and reduced in all fungicide, Actigard, or combination treatments. The combination of three ASM applications at rates of 17.5 g a.i./ha down to 4.4 g a.i./ha with the standard fungicide program was more efficacious than either fungicides or ASM alone (P < 0.001) in reducing the number of blue mold lesions per plot or number of diseased leaves harvested. The combination of fungicides and low rates of ASM (2.2 or 1.1 g a.i./ha) was similar to either fungicides or ASM (17.5 g a.i./ha) applied alone. Combining low rates of ASM with fungicide applications greatly increased efficacy and marketable yield.
47
Saito, S., T. J. Michailides, and C. L. Xiao. "Fungicide Resistance Profiling in Botrytis cinerea Populations from Blueberry in California and Washington and Their Impact on Control of Gray Mold." Plant Disease 100, no. 10 (October 2016): 2087–93. http://dx.doi.org/10.1094/pdis-02-16-0229-re.
Full textAbstract:
Gray mold caused by Botrytis cinerea is a major postharvest disease of blueberry grown in the Central Valley of California and western Washington State. Sensitivities to boscalid, cyprodinil, fenhexamid, fludioxonil, and pyraclostrobin, representing five different fungicide classes, were examined for 249 (California) and 106 (Washington) B. cinerea isolates recovered from decayed blueberry fruit or flowers. In California and Washington, 7 and 17 fungicide-resistant phenotypes, respectively, were detected: 66 and 49% of the isolates were resistant to boscalid, 20 and 29% were moderately resistant to cyprodinil, 29 and 29% were resistant to fenhexamid, and 66 and 55% were resistant to pyraclostrobin. All isolates from California were sensitive to fludioxonil, whereas 70% of the isolates from Washington showed reduced sensitivity to fludioxonil. In California, 26 and 30% of the isolates were resistant to two and three classes of fungicides, respectively. In Washington, 31, 14, 16, and 9% of the isolates were resistant to two, three, four, and five classes of fungicides, respectively. Inherent risk of the development of resistance to quinone outside inhibitor (QoI) fungicides was assessed by detecting the presence of the Bcbi-143/144 intron in gene cytb. The intron was detected in 11.8 and 40% of the isolates in California and Washington, respectively, suggesting that the risk of QoI resistance is higher in California than in Washington. On detached blueberry fruit inoculated with 11 isolates exhibiting different fungicide-resistant phenotypes, most fungicides failed to control gray mold on fruit inoculated with the respective resistant phenotypes but the mixture of cyprodinil and fludioxonil was effective against all fungicide-resistant phenotypes tested. Our findings would be useful in designing and implementing fungicide resistance management spray programs for control of gray mold in blueberry.
48
Putman, Alexander I., and John E. Kaminski. "Mowing Frequency and Plant Growth Regulator Effects on Dollar Spot Severity and on Duration of Dollar Spot Control by Fungicides." Plant Disease 95, no. 11 (November 2011): 1433–42. http://dx.doi.org/10.1094/pdis-04-11-0278.
Full textAbstract:
Management of dollar spot (incited by Sclerotinia homoeocarpa) on golf course fairways is increasingly challenging. The objectives of this study were to determine the influence of mowing frequency and plant growth regulators (PGRs) on dollar spot severity and on the residual efficacy of fungicides for control of dollar spot. Two 4-month-long studies were conducted on ‘Putter’ creeping bentgrass (Agrostis stolonifera) maintained as a fairway at the University of Connecticut. Treatments were arranged in a three-by-three-by-five factorial that assessed the influence of mowing frequency (2, 4, or 6 days week–1) and PGRs (paclobutrazol, trinexapac-ethyl, or none) on dollar spot control by five fungicide treatments (boscalid, chlorothalonil, iprodione, propiconazole, or none). Turf was mowed in the afternoon hours to minimize the confounding effect of mowing frequency on leaf wetness duration. Treatments were initiated in the late spring of 2007 and 2008, and each fungicide treatment was reapplied only when dollar spot exceeded a threshold of five infection centers plot–1. In the absence of fungicides, dollar spot severity was reduced by 63 to 90% in plots treated with paclobutrazol and by 13 to 55% in plots treated with trinexapac-ethyl. Dollar spot severity was 23 to 50% lower in plots mown 2 days week–1 compared with those mown 6 days week–1. In cases where a significant interaction was observed between mowing frequency and PGRs, dollar spot was reduced on most rating dates in plots treated with trinexapacethyl that were mown 2 days week–1 compared with those mown 6 days week–1. Survival analysis of days until threshold was met revealed that duration of control of fungicides in plots receiving paclobutrazol were 28 to 84% longer compared with plots not receiving PGR. Duration of control by fungicides was generally similar between plots treated with trinexapac-ethyl and no PGR. In general, mowing frequency did not influence duration of control. Results from this study indicate that paclobutrazol could be used to increase the treatment interval of fungicides and that mowing frequency in the absence of dew is likely to have little influence on fungicide residual efficacy. When used without fungicides, PGRs and less frequent mowing may reduce dollar spot in situations where fungicide use is limited.
49
Shynkaruk, L. М., V. V. Lykhochvor, and V. S. Vahnyak. "YIELD OF CORN DEPENDING ON THE TERMS AND MULTIPLICITY OF FUNGICIDES APPLICATION IN THE CONDITIONS OF WESTERN FOREST-STEPPE OF UKRAINE." Podilian Bulletin: Agriculture, Engineering, Economics, no. 32 (June 29, 2020): 90–98. http://dx.doi.org/10.37406/2706-9052-2020-1-11.
Full textAbstract:
The current state of corn production in the world and its importance as one of the main export crops for Ukraine has been studied. The influence of fungicides on the development of major diseases of corn by stages of development has been shown: 12 leaves, flowering phase, phase of wax ripeness of grain. Four times the application of fungicides allowed to reduce the percentage of plants affected by spotting by 15,2-15,3% relative to the control in the phase of wax ripeness of the grain. The percentage of plants affected by rust was 20,2 in the version with three treatments. Four times the use of fungicides allowed to stop the development of fusarium head blight at the level of 12,9%, against 26,3% in the control variant. Starting with double spraying with drugs, the percentage of affected plants was not more than 21,5%. Data on the effect of fungicide application on maize yield depending on the time and frequency of plant treatments are presented. The influence of fungicides on the development of major diseases of corn by stages of development has been shown. With increasing frequency of spraying received a higher yield. One-time application of fungicides allowed to obtain 0,5-1,04 t / ha of grain more than the control, double – 1,35-2,04 t / ha. The highest yield increase of +3.4 t/ha has provided the option with four applications of fungicides in the phases of 10 leaves + ejection of panicles + after flowering + grain filling. In the variant with three treatments (ejection of panicles + after flowering + grain filling) +3.13 t/ha and +2,69 t/ha to control has been received depending on the terms of application. Variants with later dates of fungicide application provided a higher increase in corn grain yield compared to earlier dates (10 leaves). It was investigated that the content of mycotoxins (fumonisin B1, T-2 toxin, zearalenone and deoxynivalenol - DON) in corn grain does not exceed the limits in any of the variants and decreases with multiplicity increase of fungicide treatments.
50
McGrath, Margaret Tuttle. "Efficacy of Conventional Fungicides for Downy Mildew in Field-Grown Sweet Basil in the United States." Plant Disease 104, no. 11 (November 2020): 2967–72. http://dx.doi.org/10.1094/pdis-11-19-2382-re.
Full textAbstract:
Application of fungicides has been the main management practice for Peronospora belbahrii, which is the most important pathogen of sweet basil in the United States. Six replicated experiments were conducted between 2010 and 2016 with field-grown basil of a susceptible cultivar exposed to naturally occurring wind-dispersed sporangiospores of P. belbahrii to evaluate conventional fungicides registered for basil downy mildew in the United States and in development for this use. This project revealed the importance for successful management of using a preventive fungicide application schedule, maintaining a 7-day application interval, and using application equipment designed to provide thorough spray coverage to plants (drop nozzles). Fungicide efficacy was assessed based on incidence of symptomatic leaves rather than disease severity, which is stringent but realistic because there is zero tolerance for disease on fresh-market herbs. Most fungicides were tested as the formulated product marketed in the United States. Oxathiapiprolin was tested as experimental formulations. Its trade name is Orondis. Overall best control was achieved in 2016. Excellent control (99% based on AUDPC values) was obtained with four fungicide programs with oxathiapiprolin, Revus, and ProPhyt, indicating this combination of chemistry was more important than specific timing for each fungicide. Ranman applied in alternation with Revus plus K-Phite was not quite as effective (89% control); this treatment was ineffective in 2015 when the 7-day spray interval was not maintained. Best treatment in 2015 was Quadris applied in alternation with Revus plus oxathiapiprolin for two of three Revus applications. Two different alternations of these fungicides also were effective. But Quadris alternated with Revus was ineffective. When tested singly, the most effective fungicides in 2013 (listed in order based on AUDPC values) were Zampro, Revus, oxathiapiprolin, and Ranman. ProPhyt was effective in 2013 but not in 2012, when another phosphorous acid fungicide, K-Phite, also was ineffective. Only oxathiapiprolin and Zampro were effective in the 2012 experiment; Revus and Ranman were ineffective. Presidio was ineffective both years. Based on the results from this study, Orondis is the most effective fungicide among those evaluated for managing basil downy mildew, and Zampro is second. Neither were labeled for this use on field-grown basil as of June 2020. Ranman applied in alternation with Revus plus K-Phite, a commonly recommended program of labeled fungicides, provided very good control.