hydrogen peroxide is involved in the sclerotial differentiation of filamentous phytopathogenic fungi.the purpose of this study was to investigate the role of h(2) o(2) and the related oxidative stress markers catalase (cat) and lipid peroxidation in the sclerotial differentiation of the phytopathogenic filamentous fungi sclerotium rolfsii, sclerotinia minor, sclerotinia sclerotiorum and rhizoctonia solani.201020681971
fungi associated with storage rots of cocoyams (colocasia spp.) in nsukka, nigeria.cocoyam (colocasia spp.) corms and cormels showing spoilage symptoms were collected from many stores in nsukka locality and examined for rot and associated fungal pathogens. aspergillus niger, botryodiplodia theobromae, corticium rolfsii, geotrichum candidum, fusarium oxysporum, and f. solani were recovered from rotten cocoyams. the representative isolates of these species caused cocoyam rot in pathogenicity tests. the rot due to a. niger, b. theobromae and c. rolfsii was extensive resulting in ...199620882465
polygalacturonase inhibitor protein from fruits of anthracnose resistant and susceptible varieties of chilli (capsicum annuum l).chilli fruit is highly susceptible to anthracnose infection at the stage of harvest maturity, due to which the fruit yield in the leading commercial variety byadgi is severely affected. field studies on screening of several varieties for resistance to anthracnose have shown that a variety of chilli ar-4/99k is resistant to anthracnose infection. in many crops, resistance to fungal attack has been correlated with pgip activity in developing fruits based on which transgenic varieties have been dev ...201021174952
effect of abiotic stress on phosphate solubilization by biocontrol fungus trichoderma sp.this study was undertaken to explore the role of trichoderma sp. in phosphate (p) solubilization and antagonism against fungal phytopathogens. all fungal isolates (se(6), kt(6), kt(28), and brt(11)) and a standard culture of t. harzianum (th-std) were able to antagonize two fungal phytopathogens (sclerotium rolfsii and rhizoctonia solani) of chickpea (cicer arietinum l.) wilt complex. transmission electron microscopic studies (tem) further confirmed ultra-cytological changes in the sclerotia of ...201121327557
superoxide radical is involved in the sclerotial differentiation of filamentous phytopathogenic fungi: identification of a fungal xanthine oxidase.this study shows that the direct indicator of oxidative stress superoxide radical (o·₂⁻) is involved in the sclerotial differentiation of the phytopathogenic filamentous fungi rhizoctonia solani, sclerotinia sclerotiorum, sclerotium rolfsii, and sclerotinia minor. the production rate of o·₂⁻ and the antioxidant enzyme superoxide dismutase (sod) levels in the sclerotiogenic fungi were significantly higher and lower, respectively, than those of their non-differentiating counterpart strains, which ...201020943149
variability in indian isolates of sclerotium rolfsii.variability among 26 isolates of sclerotium rolfsii collected from various hosts/soil samples and localities in india is reported. the isolates varied in colony morphology, mycelial growth rate, sclerotium formation, teleomorph production and sclerotial size and color. out of 26 isolates, only 4 produced the teleomorph stage on cyperus rotundus rhizome meal agar medium. mycelial incompatibility among the isolates was also seen, and out of 325 combinations, only 29 combinations (8.9%) showed comp ...200221156576
ascorbic acid might play a role in the sclerotial differentiation of sclerotium rolfsii.certain phytopathogenic fungi differentiate by forming sclerotia by an unclear biochemical mechanism. we have proposed that sclerotial differentiation might be regulated by fungal antioxidant defense. part of this defense might be ascorbic acid, which in its reduced form is a well-known antioxidant. this natural antioxidant was studied in sclerotium rolfsii in relation to oxidative-growth conditions, developmental stages and strain-differentiating ability. the transition of a sclerotial strain f ...200321156616
isolation, characterization and antifungal activity of major constituents of the himalayan lichen parmelia reticulata tayl.antifungal activity of hexane, ethyl acetate and methanol extracts of parmelia reticulata was evaluated against soilborne pathogenic fungi, namely, sclerotium rolfsii, rhizoctonia solani, r. bataticola, fusarium udum, pythium aphanidermatum and p. debaryanum by poisoned food technique. maximum antifungal activity was exhibited by hexane and ethyl acetate extracts against most of the test pathogens. secondary metabolites, namely, (±)-isousnic acid, (±)-protolichesterinic acid, atranorin, evernyl, ...201121351753
characterization of rhizosphere bacteria for control of phytopathogenic fungi of tomato.fluorescent pseudomonas spp., isolated from rhizosphere soil of tomato and pepper plants, were evaluated in vitro as potential antagonists of fungal pathogens. strains were characterized using the api 20ne biochemical system, and tested against the causal agents of stem canker and leaf blight (alternaria alternata f. sp. lycopersici), southern blight (sclerotium rolfsii sacc.), and root rot (fusarium solani). to this end, dual culture antagonism assays were carried out on 25% tryptic soy agar, k ...201121507555
insecticidal activity and fungitoxicity of plant extracts and components of horseradish (armoracia rusticana) and garlic (allium sativum).to avoid environmental pollution and health problems caused by the use of traditional synthetic pesticides, there is a trend to search for naturally occurring toxicants from plants. among the compounds discussed for anti-fungal and insecticidal activity, the natural extracts from garlic and horseradish have attracted considerable attention. the objective of this study is to determine the insecticidal and anti-fungal activity of armoracia rusticana and allium sativum l. extracts against larvae of ...201121726146
exquisite binding specificity of sclerotium rolfsii lectin toward tf-related o-linked mucin-type glycans.sclerotium rolfsii lectin (srl), a secretory protein from the soil borne phytopathogenic fungus sclerotium rolfsii, has shown in our previous studies to bind strongly to the oncofetal thomson-friedenreich carbohydrate (galß1-3galnac-ser/thr, t or tf) antigen. tf antigen is widely expressed in many types of human cancers and the strong binding of srl toward such a cancer-associated carbohydrate structure led us to characterize the carbohydrate binding specificity of srl. glycan array analysis, wh ...201121347715
sclerotial metamorphosis in filamentous fungi is induced by oxidative stress.sclerotium-forming filamentous fungi are of great agricultural and biological interest because they can be viewed as models of simple metamorphosis. they differentiate by asexually producing sclerotia but the processes involved in sclerotial metamorphosis were poorly understood. in 1997, it was shown for the first time that the sclerotial differentiation state in sclerotium rolfsii concurred with increasing levels of lipid peroxides. this finding prompted the development of a theory supporting t ...200621672779
combination of synthetic and natural products as pesticides (csynap): a new class of antifungal the present communication some dehydrated dialdol products such as 1, 5 - diphenyl pent - 1, 4 - diene - 3 - one (a1); 1, 9 - diphenylnon - 1, 3, 6, 8 - tetraene - 5 - one (a2); 1, 5 - di (2 - hydroxyphenyl) pent - 1, 4 - diene - 3 - one (a3); 1, 5 - difuran pent - 1, 4 - diene - 3 - one (a4); 1, 5 - di [4 - bis (n, ndimethyl) phenyl] pent - 1, 4 - diene - 3 - one (a5) were screened for their antifungal activity. to reduce their adverse effect on the environment, for the first time, we have a ...200721469500
Involvement of phenazines and lipopeptides in interactions between Pseudomonas species and Sclerotium rolfsii, causal agent of stem rot disease on groundnut.Aims: To determine the role of phenazines (PHZ) and lipopeptide surfactants (LPs) produced by Pseudomonas in suppression of stem rot disease of groundnut, caused by the fungal pathogen Sclerotium rolfsii. Methods and Results: In vitro assays showed that PHZ-producing Pseudomonas chlororaphis strain Phz24 significantly inhibited hyphal growth of S. rolfsii and suppressed stem rot disease of groundnut under field conditions. Biosynthesis and regulatory mutants of Phz24 deficient in PHZ productio ...201122121884
antagonistic and plant growth activity of trichoderma isolates of western himalayas.the genus trichoderma is rapidly growing colonies bearing tufted or postulate, repeatedly branched conidiophores with lageniform phialides and hyaline or green conidia born in slimy heads. 62 isolates of trichoderma species were isolated from different rhizospheric soil samples collected from different places located in western himalayas region. out of these only two species were found i.e. trichoderma hazianum and trichoderma viride. their efficacy against soil borne plant pathogens like sclero ...201021506476
scleroglucan: biosynthesis, production and application of a versatile hydrocolloid.since its first description in the early 1960s, scleroglucan attracted much attention from both academia and industry. scleroglucan is an exopolysaccharide secreted by the basidiomycete sclerotium rolfsii and appreciated as a multipurpose compound applicable in many industrial fields, including oil industry, food industry and pharmacy. in this review, the current knowledge on scleroglucan chemistry, genetics, biosynthesis and production will be summarized and different application possibilities ...201121732244
the antifungal constituents from the seeds of itoa orientalis.three new phenolic constituents, itolide a (1), itolide b (2), itoside p (3), and 1d-3-deoxy-3-hydroxymethyl-myo-inositol (4), which is described herein for the first time as a natural product, were isolated along with four other known compounds (5 to 8) from the methanol extract of the seeds of itoa orientalis hemsl by the activity-guided fractionation. their structures were determined by spectroscopic means. compounds 1 to 8 exhibited antifungal activities against sclerotium rolfsii with ic(50 ...201122233862
purification, characterization, and molecular cloning of a novel antifungal lectin from the roots of ophioglossum pedunculosum.a novel mannan-specific lectin was isolated from the roots of a traditional chinese herbal medicine, ophioglossum pedunculosum through ion-exchange chromatography and gel filtration. with a molecular mass of 19,835.7 da demonstrated by maldi-tof analysis, this novel agglutinin was designated as o. pedunculosum agglutinin (opa), specifically agglutinating human o erythrocytes and rabbit erythrocytes. the hemagglutination could be strongly inhibited by mannan and thyroglobulin, the activity of whi ...201121947760
occurrence of sclerotium rot in allium tuberosum caused by sclerotium rolfsii in this study, we characterized sporadically occurring sclerotium rot caused by sclerotium rolfsii in chinese chive (allium tuberosum roth.) in farm fields in sacheon, korea. the initial symptom of the disease was water-soaked, which progressed to rotting, wilting, blighting, and eventually death. further, mycelial mats spread over the lesions near the soil line, and sclerotia formed on the scaly stem and leaves. the sclerotia were globoid, 1~3 mm, and white to brown. the optimum temperature for ...201122783108
first report of stem rot on asiatic dayflower (commelina communis l.) caused by sclerotium rolfsii in korea.stem rot was found for the first time on the asiatic dayflower plant (commelina communis l.) in korea. a detailed description of this korean specimen is given, along with its rdna internal transcribed spacer sequence. the fungus was identified as sclerotium rolfsii saccardo based on mycological characteristics and molecular data.201122783075
Bioassays guided fractionation of Coronopus didymus for its antifungal activity against Sclerotium rolfsii.Sclerotium rolfsii Sacc. is a pathogen of about 500 plant species. In a laboratory screening bioassay, methanolic extracts of 15?mg?mL(-1) concentrations of different parts of Coronopus didymus (L.) Sm. (Brassicaceae) namely leaf, stem, inflorescence and root reduced the biomass of S. rolfsii by 67%, 26%, 40% and 58%, respectively. Methanolic root extract was successively fractionated with n-hexane, chloroform, ethyl acetate and n-butanol. All the concentrations (3.125-200?mg?mL(-1)) of ethyl ac ...201122007784
Biodegradation of tetrabromobisphenol A by oxidases in basidiomycetous fungi and estrogenic activity of the biotransformation products.Tetrabromobisphenol A (TBBPA) degradation was investigated using white rot fungi and their oxidative enzymes. Strains of the Trametes, Pleurotus, Bjerkandera and Dichomitus genera eliminated almost 1 mM TBBPA within 4 days. Laccase, whose role in TBBPA degradation was demonstrated in fungal cultures, was applied to TBBPA degradation alone and in combination with cellobiose dehydrogenase from Sclerotium rolfsii. Purified laccase from Trametes versicolor degraded approximately 2 mM TBBPA within 5 ...201121865031
scleroglucan compatibility with thickeners, alcohols and polyalcohols and downstream processing implications.thickening capacity and compatibility of scleroglucan with commercial thickeners (corn starch, gum arabic, carboxymethylcellulose, gelatin, xanthan and pectin), glycols (ethylene glycol and polyethylene glycol), alcohols (methanol, ethanol, 1-propanol and isopropanol) and polyalcohols (sorbitol, xylitol and mannitol) was explored. exopolysaccharides (epss) from sclerotium rolfsii atcc 201126 and a commercial scleroglucan were compared. compatibility and synergism were evaluated taking into accou ...201223399135
first report of sclerotium rot on cymbidium orchids caused by sclerotium rolfsii in korea.sclerotium rot was found on cymbidium orchids at seosan-si, chungcheongnam-do, korea, in july, 2010. symptoms occurred on low leaves, which turned yellowish, after which the entire plant wilted. severely infected plants were blighted and eventually died. white mycelial mats and sclerotia appeared on pseudobulbs. based on the mycological characteristics and pathogenicity, the causal fungus was identified as sclerotium rolfsii. this is the first report of new sclerotium rot on cymbidium spp. cause ...201223323053
isolation and characterization of trichoderma spp. for antagonistic activity against root rot and foliar pathogens.trichoderma, soil-borne filamentous fungi, are capable of parasitising several plant pathogenic fungi. twelve isolates of trichoderma spp. isolated from different locations of south andaman were characterized for their cultural, morphological and antagonistic activity against soil borne and foliar borne pathogens. the sequencing of these isolates showed seven different species. the isolates revealed differential reaction patterns against the test pathogens viz., sclerotium rolfsii, colletotrichu ...201123729873
biological control of chickpea collar rot by co-inoculation of antagonistic bacteria and compatible rhizobia.two hundred and seven bacteria were isolated from composts and macrofauna and screened for plant growth promoting and antagonistic traits. seven of the 207 isolates showed antagonistic activity against sclerotium rolfsii in plate culture. inhibition of s. rolfsii by the bacterial isolates ranged between 61 and 84%. two of the seven isolates were bacillus sp. and rest belonged to pseudomonas sp. two isolates, pseudomonas sp. cdb 35 and pseudomonas sp. bwb 21 was compatible with chickpea rhizobium ...201122282609
synthesis, antifungal activity and structure-activity relationships of vanillin oxime-n-o-alkanoates.vanillin oxime-n-o-alkanoates were synthesized following reaction of vanillin with hydroxylamine hydrochloride, followed by reaction of the resultant oxime with acyl chlorides. the structures of the compounds were confirmed by ir, 1h, 13c nmr and mass spectral data. the test compounds were evaluated for their in vitro antifungal activity against three phytopathogenic fungi macrophomina phaseolina, rhizoctonia solani and sclerotium rolfsii by the poisoned food technique. the moderate antifungal a ...201223413571
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