Fungicide treatment of sunflower seed to inhibit germination of admixed sclerotia of Sclerotinia sclerotiorum

1986 ◽  
Vol 26 (4) ◽  
pp. 489 ◽  
Author(s):  
JK Kochman ◽  
PW Langdon
Keyword(s):  
Sclerotinia Sclerotiorum ◽  
Chemical Control ◽  
Direct Contact ◽  
Sunflower Seed ◽  
Potato Dextrose Agar ◽  
Apparent Effect ◽  
Thiophanate Methyl ◽  
Fungicide Treatment ◽  
Wettable Powder ◽  
Low Levels

Sunflower seed lots infected with sclerotia of Sclerotinia sclerotiorum provide a means of dispersal of the fungus. To find a chemical control, sclerotia were dusted or dipped with 19 chemical formulations. Eight of these (benomyl 50%, benomyl 15% plus lindane 1%, thiabendazole wettable powder, thiabendazole 45% water-based flowable, iprodione 50%, dithianon 75%, omadine 50% and thiophanatemethyl 70%) completely inhibited germination of sclerotia when in direct contact with and covering the organism. Sclerotia were able to germinate if these chemicals were removed by washing, but germination was significantly lower for those sclerotia which had been treated with benomyl 50%, benomyl 15% plus lindane 1% (Bennel 13, thiabendazole 90% and 45%, iprodione 50% and thiophanate-methyl 70% than for dithianon 75% and omadine 50%. When sclerotia were buried in moist soil for 1 month those treated with formulations of benomyl, thiabendazole and iprodione did not germinate on potato dextrose agar, while the germination percentages of those treated with dithianon, ornadine and thiophanate-methyl were not significantly different from that for germination of sclerotia which had not been treated. When thiabendazole, benomyl and iprodione were used at 3 rates to treat sunflower seed infested with sclerotia, thiabendazole was the most effective fungicide in preventing germination of sclerotia. This result was confirmed when the fungicide was used commercially to treat lots of sunflower seed containing sclerotia. As thiabendazole had no apparent effect on gerrnination of sunflower seed it could be used to treat sunflower seed containing low levels of sclerotia to prevent previously uninfested areas being contaminated with S. sclerotlorum during sowing operations.

scholarly journals Biological and chemical control of Sclerotinia sclerotiorum using Trichoderma spp. and Ulocladium atrum and pathogenicity to bean plants

2010 ◽  
Vol 53 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Girlene Soares de Figueirêdo ◽  
Lívio Carvalho de Figueirêdo ◽  
Francinete Carla Nunes Cavalcanti ◽  
Angela Coimbra dos Santos ◽  
Antonio Felix da Costa ◽  
...  
Keyword(s):  
Sclerotinia Sclerotiorum ◽  
Chemical Control ◽  
Statistical Difference ◽  
Phaseolus Vulgaris L ◽  
Trichoderma Spp ◽  
Thiophanate Methyl ◽  
Bean Plants ◽  
Antagonistic Potential

Four isolates of Sclerotinia sclerotiorum were tested for pathogenicity in IPA-10 variety bean plants (Phaseolus vulgaris L.), and all were pathogenic. Biological control in vitro was evaluated using eight isolates of Trichoderma spp. and, one of Ulocladium atrum. Chemical control in vitro with fungicides Thiophanate methyl, Iprodione and Carbendazim was also tested. Except U. atrum, all Trichoderma isolates showed antagonistic potential against S. sclerotiorum, where isolate 3601 presented the best performance. Thiophanate methyl chemical control was the most efficient. This fungicide and isolate 3601were compared in vivo in greenhouse. There was statistical difference between the treatments, and the application of fungicide and antagonist before the pathogen was the most efficient approach, reducing the percentage of pathogenicity to 32.94% and 37.04%, respectively.

scholarly journals SELECTION OF HERBICIDES TARGETING THE USE IN CROP SYSTEMS CULTIVATED WITH SHOWY CROTALARIA

2015 ◽  
Vol 33 (3) ◽  
pp. 521-534 ◽  
Author(s):  
G. B. P BRAZ ◽  
R. S OLIVEIRA JR ◽  
J. CONSTANTIN ◽  
H. K. TAKANO ◽  
C. A. CHASE ◽  
...  
Keyword(s):  
Nitrogen Fixation ◽  
Chemical Control ◽  
Clayey Soil ◽  
Chlorimuron Ethyl ◽  
High Production ◽  
Low Levels ◽  
Postemergence Herbicides ◽  
Potential Use ◽  
Selection Of

ABSTRACT The increase in the area planted with Crotalaria spectabilishas occurred by several factors, highlighting the potential to reduce the nematodes, nitrogen fixation and the high production of biomass. By becoming a species sown as a crop, it is necessary to control the weeds that coexist with showy crotalaria. This change in the use of this crop creates the possibility of this specie becoming a weed. The aim of this study was to assess the potential use of herbicides applied in preemergence and postemergence of C.spectabilisfor different purposes (control of volunteer and selectivity plants). Three experiments were installed in a greenhouse (two with herbicides applied in preemergence - in soils with distinct textural categories; and one experiment with herbicides applied in postemergence). The results of the experiments with herbicides applied in preemergence showed that: amicarbazone, atrazine, diuron, metribuzin, prometryn, fomesafen and sulfentrazone showed effectiveness for control of C.spectabilis in clayey soil. Besides these, flumioxazin and isoxaflutole also showed potential to be used in the control of showy crotalaria in soils with loam texture. In relation to the postemergence herbicides, atrazine, diuron, prometryn, flumioxazin, fomesafen, lactofen, saflufenacil, amonio-glufosinate and glyphosate can be used aiming the chemical control of C.spectabilis. Herbicides chlorimuron-ethyl, diclosulan, imazethapyr, pyrithiobac-sodium, trifloxysulfuron-sodium, clomazone, pendimethalin, S-metolachlor and trifluralin applied in preemergence, and imazethapyr, pyrithiobac-sodium, flumiclorac, bentazon and clethodim applied in postemergence caused low levels of injury to C.spectabilis plants, making necessary the development of new searches to ensure the selectivity of these products.

scholarly journals Stimulatory Effects of Sublethal Doses of Dimethachlon on Sclerotinia sclerotiorum

Plant Disease ◽  
2014 ◽  
Vol 98 (10) ◽  
pp. 1364-1370 ◽  
Author(s):  
Feng Zhou ◽  
Hong-Jie Liang ◽  
Ya-Li Di ◽  
Hong You ◽  
Fu-Xing Zhu
Keyword(s):  
Oilseed Rape ◽  
Sclerotinia Sclerotiorum ◽  
Mycelial Growth ◽  
Plant Disease ◽  
Pathogenic Fungi ◽  
Potato Dextrose Agar ◽  
Detached Leaves ◽  
Sublethal Doses ◽  
Fungal Phytopathogens ◽  
Plant Disease Management

Growth and virulence stimulations of sublethal doses of fungicides on plant-pathogenic fungi and oomycetes have been reported and the stimulatory effects are potentially relevant to plant disease management. Sclerotinia sclerotiorum is one of the most devastating and economically important necrotrophic fungal phytopathogens, capable of infecting more than 400 species of plants worldwide. In order to study stimulatory effects of sublethal doses of fungicides on S. sclerotiorum, 55 dimethachlon-sensitive isolates and 3 dimethachlon-resistant isolates of S. sclerotiorum were assayed to determine effects of sublethal doses of dimethachlon on mycelial growth rate on potato dextrose agar (PDA) media and virulence on oilseed rape plants. Results showed that all 3 dimethachlon-resistant isolates and 13 of the 55 sensitive isolates exhibited stimulatory responses to sublethal doses of dimethachlon. Dimethachlon-resistant isolates grew significantly (P < 0.05) faster on PDA media amended with dimethachlon at 0.5 to 4 μg/ml than on fungicide-free PDA media. As for virulence on detached leaves of oilseed rape plants, lesion diameters of dimethachlon-resistant isolates after growth on PDA media amended with dimethachlon at 0.5 to 2 μg/ml were significantly larger (P < 0.05) than the control. The maximum stimulatory effects were 42.40 to 59.80%. In pot experiments, for both dimethachlon-sensitive and -resistant isolates, significant (P < 0.05) virulence stimulations were observed after spraying with dimethachlon at a concentration of 2 μg/ml. After growing on dimethachlon-amended PDA media, H2O2 sensitivity of S. sclerotiorum decreased significantly (P < 0.05) compared with the nonamended PDA control.

scholarly journals Effects of Bicarbonate on the Respiration and Glycolytic Activity of Boar Spermatozoa

1978 ◽  
Vol 31 (4) ◽  
pp. 385 ◽  
Author(s):  
RN Murdoch ◽  
WD Davis
Keyword(s):  
Carbon Dioxide ◽  
Energy Source ◽  
Oxygen Consumption ◽  
Apparent Effect ◽  
Glycolytic Activity ◽  
Low Levels ◽  
Presence And Absence ◽  
Boar Spermatozoa

The metabolism of washed boar spermatozoa was studied in the presence and absence of low levels of bicarbonate (6 mM) and carbon dioxide (2 %). Bicarbonate stimulated the oxygen consumption of the spermatozoa but had no apparent effect on glycolysis. The stimulatory effect of bicarbonate on respiration depended on the presence of a utilizable exogenous energy source such as glucose, fructose, lactate, or pyruvate and no stimulation occurred when no substrate was added or when acetate was used as substrate. The response of the spermatozoa to bicarbonate also depended on the presence of adequate concentrations of potassium (5 mM) and to a lesser extent magnesium (1 mM).

scholarly journals CHEMICAL CONTROL OF SEED-BORNE FUNGAL PATHOGENS OF SUNFLOWER / CONTROL QUÍMICO DE PATÓGENOS DE SEMILLAS EN GIRASOL / MESURES DE DÉFENSE CONTRE LES CHAMPIGNONS PATHOGÈNES DU TOURNESOL TRANSMIS PAR LA SEMENCE

Helia ◽  
2001 ◽  
Vol 24 (35) ◽  
pp. 67-72
Author(s):  
A Rauf Bhutta ◽  
M.M. Rahber Bhatti ◽  
Iftikhar Ahmad ◽  
Ishrat Sultana
Keyword(s):  
Seed Germination ◽  
Chemical Control ◽  
Sunflower Seed ◽  
Fungal Pathogens ◽  
Considerable Improvement ◽  
Complete Elimination ◽  
Fungal Population ◽  
Percent Increase ◽  
And Control

SUMMARYFive fungicides, namely Tecto, Benlate, Bayton, Topsin and Derosal, were evaluated for their effect on seed germination and control of major seed-borne pathogens of sunflower. Two sunflower cultivars, HO-1 and NK-212, naturally infected with important seed-borne fungi were treated with these fungicides at 1.5, 2.0, 2.5, 3.0 g/kg. All the fungicides under study controlled the seed-borne fungi and increased the germination of sunflower seed to various levels. Tecto and Benlate in both cultivars gave better performance in reducing the fungal population and increasing seed germination. Topsin and Derosal also reduced the fungal population at higher dosage but there was no considerable improvement in germination. The use of fungicides at 2.5 g/kg provided almost complete elimination of fungi and 8-10 percent increase in seed germination as compared to the use of fungicides at 2 g/kg.

Comparative studies on myceliogenic germination of tan sclerotia of Sclerotinia sclerotiorum and Sclerotium rolfsii

1989 ◽  
Vol 67 (5) ◽  
pp. 1395-1401 ◽  
Author(s):  
H. C. Huang ◽  
S. K. Sun
Keyword(s):  
Sclerotinia Sclerotiorum ◽  
Room Temperature ◽  
Sclerotium Rolfsii ◽  
Soil Surface ◽  
Time Lapse ◽  
Potato Dextrose Agar ◽  
Damping Off ◽  
Seed Rot ◽  
Myceliogenic Germination ◽  
Exogenous Nutrients

Tan-colored sclerotia of Sclerotium rolfsii and of an aberrant strain of Sclerotinia sclerotiorum that were freshly harvested from 5-week-old cultures on potato dextrose agar or stored at room temperature in paper bags for 4 weeks germinated myceliogenically on moist field soil without exogenous nutrients. A comparative study by time-lapse photomicroscopy revealed similarity in the mode of myceliogenic germination of sclerotia of the two species. The germination appeared to be of the hyphal type in both species and was characterized by the emergence of individual hyphae through the rind. There was no evidence of eruptive type of germination in any of the strains tested. Although several hyphae often emerged through the same spot of the rind, these hyphae emerged singly, and the time-lapse photomicrographs showed no evidence of eruptive germination. While most of the germinated sclerotia of S. rolfsii developed into colonies within 4 days of incubation on moist soil, the development of colonies from germinating sclerotia of S. sclerotiorum appeared to be slow, taking up to 28 days. Results of the inoculation studies showed that mycelia from the germinated sclerotia of S. rolfsii were able to infect and cause seed rot and damping-off of canola and alfalfa, which were planted near the soil surface at a distance of at least 15 mm from the sclerotium, without providing exogenous nutrients.

scholarly journals Organizing the medical care for the COVID-19 patients in non-infectious Moscow hospital: reassignment experience

2020 ◽  
Vol 92 (11) ◽  
pp. 31-37
Author(s):  
I. G. Nikitin ◽  
A. V. Melekhov ◽  
M. A. Sayfullin ◽  
S. S. Agafonov ◽  
S. A. Bedritskiy ◽  
...  
Keyword(s):  
Hospital Mortality ◽  
Direct Contact ◽  
Healthcare Workers ◽  
Working Process ◽  
National Medical ◽  
Prognostic Accuracy ◽  
Acceptable Quality ◽  
Area Under Roc Curve ◽  
Low Levels ◽  
Run Up

Aim. To present the results of work of National Medical Research Center of Treatment and Rehabilitation, reassigned for COVID-19 patients treatment during pandemic. Run-up methodology, procedures and working process organization are detailed. Materials and methods. 354 COVID-19 patients were treated from 13.04.2020 to 10.06.2020 [age 59 (470) years, 56% women, body mass index 28.5 (24.932.2) kg/m2]. Patients were admitted at 8 (611) day of sickness. In-hospital stay was 16 (1420) days. Results. NEWS scale at the day of admittance was 2 (14); 2 (13) in patients discharged alive and 6 (47) in died patients, p=0.0001. So prognostic accuracy of NEWS scale was confirmed as very well (area under ROC-curve = 0.819). 69 patients (19.5%) were treated at intensive care department for 7 (413) days. 13 patients died, 11 of them had COVID-19 as direct or indirect cause of death. Total in-hospital mortality was 3.67%, in-hospital mortality of COVID-19 patients 3.1%. 17 healthcare workers (HCW), contacted with COVID-19 patients were infected (2.67%). 4 HCW, who had no direct contact with patients were also infected and 7 HCW were infected before the first patient was admitted. No one of them died. Conclusion. Complex tasks of healthcare organization during COVID-19 pandemic can be solved quickly with acceptable quality, characterized by low levels of patients; mortality and HCW infection.

scholarly journals Effect of Osmotic and Matric Potentials on Sclerotinia minor and Sclerotinia sclerotiorum Virulence on Peanut

2016 ◽  
Vol 4 (3) ◽  
pp. 147-158 ◽  
Author(s):  
Ahmed Abd-Elmagid ◽  
Robert Hunger ◽  
Carla Garzón ◽  
Mark Payton ◽  
Ho-Jong Ju ◽  
...  
Keyword(s):  
Sclerotinia Sclerotiorum ◽  
Vegetative Growth ◽  
Mycelial Growth ◽  
Potato Dextrose Agar ◽  
Matric Potential ◽  
Progress Curve ◽  
High Concentrations ◽  
Matric Stress ◽  
Osmotic Potentials ◽  
Sclerotial Germination

The effect of osmotic and matric potentials on mycelial growth, sclerotia production, germination, and virulence of two isolates of Sclerotinia sclerotiorum, and one isolate of S. minor were studied on potato dextrose agar (PDA) media adjusted with KCl, glycerol, or agar. Osmotic potentials created by KCl and glycerol significantly reduced vegetative growth of the three isolates. On matrically adjusted PDA, vegetative growth of the three isolates was not negatively affected by matric stress up to -3.5 MPa. When KCl was the osmoticum, sclerotia number did not follow a consistent pattern. However, sclerotia number decreased when osmotic stress created by glycerol was increased. Matric stress was not a consistent factor affecting sclerotia production by both species.  However, the highest levels of matric stress -3.0 and -3.5 MPa significantly reduced sclerotia production by both species. In general, there was a trend toward lower sclerotial germination with increasing osmotic and matric stress. Pathogenicity of S. minor and S. sclerotiorum on the peanut cultivar (Okrun) was reduced by high concentrations of KCl. Mycelia of both species produced at high matric potential -3.5 MPa did not differ in pathogenicity on Okrun compared with mycelia grown on non-amended PDA. In water-stressed-Okrun, induced by polyethylene glycol 8000, the Area under Disease Progress Curve (AUDPC) was significantly decreased. The relevance of these results to the behavior of S. minor and S. sclerotiorum, and their pathogenicity on peanut is discussed.

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