Biological control of Sclerotinia sclerotiorum on aerial parts of plants by the hyperparasite Coniothyrium minitans

1. Two fungi, Coniothyrium minitans Campbell and Trichoderma viride Pers. ex Fr., were grown on autoclaved crushed sclerotia of the species Sclerotinia sclerotiorum, which they parasitize. 2. in vitro the crude culture filtrates would lyse walls isolated from hyphal cells or the inner pseudoparenchymatous cells of the sclerotia, in which a branched β-(1→3)-β-(1→6)-glucan, sclerotan, is a major constituent. 3. Chromatographic fractionation of the enzymes in each culture filtrate revealed the presence of several laminarinases, the most active being an exo-β-(1→3)-glucanase, known from previous studies to attack sclerotan. Acting alone this brought about a limited degradation of the glucan, but the addition of fractions containing an endo-β-(1→3)-glucanase led to almost complete breakdown. A similar synergism between the two enzymes was found in their lytic action on cell walls. 4. When acting alone the endo-β-(1→3)-glucanase had a restricted action, the products including a trisaccharide, tentatively identified as 62-β-glucosyl-laminaribiose. 5. These results are discussed in relation to the structure of the cell walls and of their glucan constituents.

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Biological Control of Sclerotinia Sclerotiorum and Botrytis Spp.

Biological Control of Plant Diseases ◽

10.1007/978-1-4757-9468-7_36 ◽

1992 ◽

pp. 267-271 ◽

Cited By ~ 4

Author(s):

Nyckle J. Fokkema ◽

Matthijs Gerlagh ◽

Jürgen Köhl

Keyword(s):

Biological Control ◽

Sclerotinia Sclerotiorum

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Effect of timing of application and population dynamics on the degree of biological control of Sclerotinia sclerotiorum by bacterial antagonists

Annales de Réadaptation et de Médecine Physique ◽

10.1016/s0168-6496(04)00150-3 ◽

2004 ◽

Author(s):

S SAVCHUK

Keyword(s):

Biological Control ◽

Population Dynamics ◽

Sclerotinia Sclerotiorum ◽

Bacterial Antagonists

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Preliminary Field Plot Trials on Biological Control of Sclerotinia trifoliorum by Coniothyrium minitans

Plant Pathology ◽

10.1111/j.1365-3059.1975.tb01874.x ◽

1975 ◽

Vol 24 (2) ◽

pp. 109-113 ◽

Cited By ~ 29

Author(s):

G. J. TURNER ◽

H. T. TRIBE

Keyword(s):

Biological Control ◽

Field Plot ◽

Coniothyrium Minitans ◽

Sclerotinia Trifoliorum

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Sensitivity of Ulocladium atrum, Coniothyrium minitans, and Sclerotinia sclerotiorum to benomyl and vinclozolin

Canadian Journal of Botany ◽

10.1139/b02-077 ◽

2002 ◽

Vol 80 (8) ◽

pp. 892-898 ◽

Cited By ~ 10

Author(s):

G Q Li ◽

H C Huang ◽

S N Acharya

Keyword(s):

Growth Inhibition ◽

Sclerotinia Sclerotiorum ◽

Spore Germination ◽

Mycelial Growth ◽

Germination Rate ◽

Effective Concentration ◽

Coniothyrium Minitans ◽

Inhibition Concentration ◽

Maximum Inhibition ◽

Germ Tubes

Assays on mycelial growth and spore germination were carried out to determine the sensitivity of the biocontrol agents Ulocladium atrum and Coniothyrium minitans and the plant pathogen Sclerotinia sclerotiorum to benomyl and vinclozolin. Ulocladium atrum was more tolerant to these fungicides than C. minitans and S. sclerotiorum. The 50% effective concentration (EC50) of U. atrum based on the mycelial growth inhibition was 1467.3 µg active ingredient (a.i.)/mL for benomyl and 12.6 µg a.i./mL for vinclozolin, and the maximum inhibition concentration was higher than 4000 µg a.i./mL for both fungicides. For C. minitans and S. sclerotiorum, however, the EC50 based on mycelial growth inhibition was lower than 1 µg a.i./mL. After incubation for 24 h at 20°C, the germination rate of U. atrum conidia was 9099% on potato dextrose agar (PDA) amended with benomyl at 100500 µg a.i./mL or vinclozolin at 10500 µg a.i./mL. At these concentrations, germ tubes of U. atrum developed into long, branched hyphae in benomyl treatments, but they remained short and clustered in vinclozolin treatments. Pycnidiospores of C. minitans and ascospores of S. sclerotiorum germinated on PDA amended with benomyl at 100500 µg a.i./mL, but the germ tubes did not grow further. Spore germination of C. minitans and S. sclerotiorum was less than 3.2% on PDA amended with vinclozolin at 10500 µg a.i./mL after 24 h. This is the first report on the sensitivity of U. atrum and C. minitans to benomyl and vinclozolin. The results suggest that it is possible to control S. sclerotiorum using a combination of U. atrum and benomyl or vinclozolin.Key words: fungicides, mycelial growth, spore germination, integrated pest management.

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