Showing papers on "Sclerotinia sclerotiorum published in 1971"
TL;DR: It was found that 3,5-dihalo-substituents on the benzene moiety are essential to high antifungal activity against Sclerotinia sclerotiorum.
Abstract: The structure-activity relationships of l-phenylpyrrolidine-2,5-dione derivatives were investigated on Sclerotinia sclerotiorum by the agar dilution method. In addition, several representative compounds were tested for antimicrobial spectra in vitro with 15 pathogenic microbes and for foliage protection activity in green house tests with rice blast, rice brown spot, rice sheath blight and kidney bean stem rot. It was found that 3,5-dihalo-substituents on the benzene moiety are essential to high antifungal activity against Sclerotinia sclerotiorum. Generally, l-(3′,5′-dihalophenyl)pyrrolidine-2,5-diones are active against Corticiaceae, Dematiaceae, Pleosporaceae and Sclerotiniaceae, especially active against Sclerotinia sclerotiorum and Botrytis cinerea (the conidia form of Sclerotinia fuckeliana). N-(3,5-Dichlorophenyl)itaconimide showed a peculiarly broad antimicrobial spectrum. In green house tests, these compounds showed high activity against rice brown spot, rice sheath blight and kidney bean stem rot...
67 citations
TL;DR: In this paper, the structure-activity relationship of 3-phenyloxazolidine-2, 4-diones, 3phenyl-4-imino-oxozolidine -2-ones and nphenyl carbamates were investigated on Sclerotinia sclerotiorum by the agar medium dilution method.
Abstract: The structure-activity relationships of 3-phenyloxazolidine-2, 4-diones, 3-phenyl-4-imino-oxazolidine-2-ones and n-phenylcarbamates were investigated on Sclerotinia sclerotiorum by the agar medium dilution method. In addition, antimicrobial spectra of several compounds against other 15 pathogenic microbes were investigated by the same method. In each series, 3, 5-dihalo-substituents on benzene ring are essential to high antifungal activity against Sclerotinia sclerotiorum and in the case of n-phenylcarbamates, it is necessary that the α-position of alcohol moiety is substituted by such a group as cyano group, ethoxy-carbonyl group or carbamoyl group. α-Cyanoisopropyl N-(3, 5-dichlorophenyl) carbamate, 3-(3′, 5′-dichlorophenyl)-5, 5-dimethyl-4-iminooxazolidine-2-one and 3-(3′, 5′-dichlorophenyl)-5, 5-dimethyloxazolidine-2,4-dione were the most effective and completely inhibited the mycelial growth of Sclerotinia sclerotiorum at 3.2 γm (about l.0 ppm). In general, 3-(3′, 5′-dichlorophenyl) oxazolidine-2, 4-...
44 citations
TL;DR: Study of sclerotium ontogeny in association with biochemical and serological studies, should be useful as an aid to taxonomy.
Abstract: The ontogeny of sclerotia of Sclerotinia sclerotiorum (Lib.) de Bary and S. trifoliorum Erikss., both of which produce large sclerotia, was compared with that of S. libertiana Fuckel and S. minor Jagger, which produce smaller sclerotia. Initials of the large-type sclerotium develop terminally by the repeated branching of long aerial, primary hyphae and fusion of the branches. Initials are formed in close proximity and several initials coalesce to form one sclerotium. Initials of the smaller-type sclerotium develop in positions lateral to the main hyphae by the repeated branching, interweaving and frequent anastomoses of short aerial hyphae. This is a simple type of development from strands. Initials are not normally formed in close proximity and coalescence of hyphal aggregates is less frequent. Small hyphal aggregates which developed into rounded spore-like cells were produced by all isolates. The differences between the two sclerotium types are due to the growth patterns of the mycelia of the two groups. The ontogenetic diversity suggests taxonomie differences between them. Study of sclerotium ontogeny in association with biochemical and serological studies, should be useful as an aid to taxonomy.
36 citations
TL;DR: The exudate from sclerotia of 6-day-old cultures of Sclerotinia sclerOTiorum (Lib.) DeBary was found to contain cations, lipids, ammonia, amino acids, proteins, and various enzymes.
Abstract: The exudate from sclerotia of 6-day-old cultures of Sclerotinia sclerotiorum (Lib.) DeBary was found to contain cations, lipids, ammonia, amino acids, proteins, and various enzymes. Disc-gel electr...
33 citations
TL;DR: The pH of the culture filtrate usually increased slowly during the growth period when the fungus grew poorly and no sclerotia were formed, but a combination of glucose plus trehalose or polyols resulted in increased growth and the formation of sclerotsia.
Abstract: Sclerotinia sclerotiorum (Lib.) D By. was grown in stationary liquid mineral-salts medium, pH 4.3, containing various carbon sources and the weight of mycelia and sclerotia was determined at regular intervals. When grown on various glucose concentrations (0–24 g of C/l), more sclerotia were produced at 8–12 g of C/l. Sclerotia were not usually formed in shake cultures. The ability of the fungus to use other carbon sources for growth and sclerotium formation was tested at 12 g of C/l in the stationary mineral-salts medium. The highest weights of mycelia and sclerotia occurred with raffinose, sucrose, maltose, lactose, d-mannose, d-glucose, d-fructose or l-arabinose. Good growth but decreased sclerotium production were found on cellobiose and d-xylose. Reduced or poor growth, a long lag period and few or no sclerotia occurred on trehalose, melibiose, l-sorbose, l-rhamnose, d-ribose, d-arabinose, l-xylose or 8 polyols. No growth was observed with erythritol or i-inositol. A combination of glucose plus trehalose or polyols resulted in increased growth and the formation of sclerotia. Organic acids supported little or no growth and no sclerotia were produced. Generally culture filtrates which supported growth and formation of sclerotia became acid (about pH 3.5). The pH of the culture filtrate usually increased slowly during the growth period when the fungus grew poorly and no sclerotia were formed. The alcoholsoluble sugars and polyols present in culture filtrates, mycelia and sclerotia were determined by paper and thin-layer chromatography. Regardless of the carbon source, mannitol was usually present in culture filtrates. The occurrence of other compounds in the filtrates depended on the carbon source. Trehalose, mannitol and usually small quantities of glucose or fructose were present in mycelia and sclerotia from all carbon sources. Galactitol or pentitols occurred in mycelia and sclerotia when the fungus grew on galactose and oligosaccharides containing galactose or the corresponding pentose, sugars. Acid hydrolyzates of the alcohol-insoluble fraction of mycelia or sclerotia contained glucose, smaller amounts of galactose and mannose and traces of ribose and rhamnose.
27 citations
TL;DR: Results indicate that there is a short growth phase during which the bulk of material which will constitute the Sclerotium is incorporated into initials and a longer maturation phase where there is little movement of material into sclerotia from the substrate but during which changes in internal physiological organization take place.
Abstract: Changes in composition, 14CO2 evolution, exudation and in the distribution of radioactive carbon compounds in different fractions of sclerotia were followed during their development on a defined medium containing [14C]-glucose Results indicate that there is a short growth phase during which the bulk of material which will constitute the Sclerotium is incorporated into initials This is followed by a longer maturation phase where there is little movement of material into sclerotia from the substrate but during which changes in internal physiological organization take place
21 citations
18 citations
TL;DR: Liquid droplets commonly observed on developing sclerotia of Sclerotinia sclerotsiorum were found to be enveloped by small sacs.
Abstract: Liquid droplets commonly observed on developing sclerotia of Sclerotinia sclerotiorum were found to be enveloped by small sacs. These sacs were present at all stages of sclerotia development when t...
18 citations
TL;DR: The pathogen could tolerate a wide range of pH, but good growth and sclerotial formation were favoured at pH varying from 4 to 5.5.
Abstract: Sclerotinia sclerotiorum causing foot rot ofGaillardia pulchella was found to grow well on semi-synthetic media. Amongst synthetic media, Richard's medium and Czapek's medium supported good growth and sclerotial formation. Glucose among monosaccharides and maltose followed by sucrose, among disaccharides, were good sources of carbon for the growth of the fungus. Glycerol and mannitol were observed to be poor sources. Best sclerotial production was favoured by glucose. Ammonium sulphate was utilized well followed by potassium and sodium nitrates. Ammonium phosphate favoured best sclerotial formation. The pathogen could tolerate a wide range of pH, but good growth and sclerotial formation were favoured at pH varying from 4 to 5.5.
11 citations
TL;DR: Studies on loss of weight by sclerotia of different ages at zero relative humidity suggest that the rind formed during growth and maturation is freely permeable to water.
Abstract: The uptake of [14C]glucose by slices of sclerotia of Sclerotinia sclerotiorum of different ages was investigated. The highest levels of incorporation of label into ethanol-soluble and ethanol-insoluble compounds were found in Sclerotium tissues 4 days old. Tissues older or younger than this showed lower levels of incorporation. Studies on loss of weight by sclerotia of different ages at zero relative humidity suggest that the rind formed during growth and maturation is freely permeable to water.
4 citations