Abstracts

No. 34, Vol. 3, 2000

 

REVIEWS AND DISCUSSIONS

Tarchevsky I.A., Chernov V.M. Molecular aspects of phytoimmunity // Mycol. and phytopat. V. 34, N 3, 2000. P. 1-11.

Abstract

Studies on mechanisms of perception and transduction of elicitor signals to plant cell genome are reviewed. Participation of different signal systems (including cAMP-, MAPK-, Ca2+-lipoxygenase-, superoxide synthase-, NO-synthase systems) in forming of defence response to pathogens is discussed. Attention is primarily paid to interrelations between mycoplasms and plants.

 

BIODIVERSITY, TAXONOMY, ECOLOGY

Sidorova I.I., Velikanov L.L. Bioactive substances of agaricoid basidiomycetes and their possible role in regulation of myco- and microbiota structure in soils of forest ecosystems. I. Antibiotic activity of water extracts from basidioms of several dominant agaricoid basidiomycetes // Mycol. and phytopat. V. 34, N 3, 2000. P.11-18.

Abstract

Fiftythree species (477 samples) of dominating agaricoid basidiomycetes (AB) from 14 families were tested for presence of bioactive metabolites. Effect of these substances on bacteria, actinomycetes and micromycetes isolated from both hyphosphere of studied AB and soil outside their colonies was investigated. Standard tests were applied as well.

Water extracts from studied AB basidiomes inhibited growth of grampositive bacteria and/or yeasts. Water extracts was shown to be active also against soil micromycetes and usually eliminated Penicillium thomii (inhibited in 59.06 % of studied AB), P. nigricans (56.25 %) and Micromucur ramannianus (73.58 %) from AB colonies. At the same time P. purpurogenum, Pseudomonas fluorescens and some other bacteria and actinomycetes isolated from AB colonies appeared to be resistant to bioactive metabolites of studied AB. This data agrees well with typical effect of studied AB species on soil biota and shows perspectives for further confirmation of hypothesis on allelochemical activity of AB as regulators of the structure of microbial communities in forest soils and litter.

Petrova-Nikitina A.D., Mokeeva V.L., Zheltikova T.M., Chekunova L.N., Antropova A.B., Mokronosova M.A., Bilanenko E.N., Sizova T.P. Mycobiota of house dust in the city of Moscow // Mycol. and phytopat. V. 34, N 3, 2000. P.25-34.

Abstract

Nintyfive species of micromycetes and 4 spp. of yeast were found in the house dust from 54 Moscow apartments. The soilborne fungi predominated in the house dust mycobiota. As to species diversity and frequency, genera Penicillium (34 spp., frequency 100 %) and Aspergillus (25 spp., frequency 91 %) were found to be dominant. The abundance of Penicillium was 3 times higher than that of Aspergillus, Penicillium was superdominant in the house dust (its share in mycobiota was 26 %). All micromycetes formed three ecological groups. All yeasts were found in the house dust with high frequency of 24 to 50 %. Cryptococcus albidus and Debaryomyces hansenii dominated in both abundance and frequency (2101.2 x 103 CFU/g of dust, frequency 50 % and 1302.9 x 103 CFU/g of dust, frequency 24 %, respectively). Micromycetes Penicillium chrysogenum, P. verrucosum var. cyclopium, Aspergillus penicilloides, Alternaria alternate! and Penicillium sp. (P. olsoni) and yeasts C. albidus, D. hansenii are most common in house dust mycobiota of Moscow. Several of the species found are known to be potential sourse of allergens: namely Alternaria altemata, Aspergillus niger, Aspergillus flavus, Penicillium chrysogenum, and Aureobasidium pullulans.

Mazheika I S., Grube E.T., Kamzolkina O.V., Dyakov Yu.T. Instability of homokaryotic strains of Agaricus bisporus // Mycol. and phytopat. V. 34, N 3, 2000. P.34-39.

Abstract

A few homokaryotic strains of Agaricus bisporus has been investigated during the one year period that helped to offer classification of morphological instability. Several types of instability were depicted and the main division is based on ability to preserve or lose the motherline in process of cultivation. Presence of the mating type switching mechanism (such as in yeasts and some basidiomycetes) were also looked for in one heterokaryotic strain, obtained from homokaryotic mycelium. We suggest that if such mechanism is present it is realised only through copying of a parent allele from a silent to active mt-locus.

 

PHYSIOLOGY, BIOCHEMISTRY, BIOTECHNOLOGY

Sukharevich V.I., Zaitseva T. B., Medvedeva N.G., Sukliarevich M.E., Kuzikova I.L. Effect of biocides of various chemical origin on synthesis of pigments in cellulose destroying fungi //Mycol. and phytopat. V. 34, N 3, 2000. P.39-43.

Abstract

Different effects of biocides such as catamine, imbrizine, methacid, and formaldehyde on growth and synthesis of pigments in cellulose destroying fungi were found. Increase in both pigments' concentration in medium and fungal biomass were shown when biocides were added. It was also found that biocides inhibited sporogenesis of fungi.

Sukharevich V.I., Kuzikova I.L, Medvedeva N.G., Gridneva Yu.A. Growth of micromycetes and production of pigments on media containing fungicides and inhibitors of pigment synthesis // Mycol. and phytopat. V. 34, N 3, 2000. P.43-48.

Abstract

Effect of different fungicides on growth and biosynthesis of pigments by A. niger, A. terreus, A. flavus and P. funiculosus were studied. Biosynthesis of pigments was shown to increase by 160-200 % on medium containing fungicides. At the same time biosynthesis of pigments was inhibited on the medium contained inhibitors of pigmentogenesis (EDTA in concentration of 0.1 % or DMSO in concentration of 1.0 %). In the case when both fungicides and DMSO or EDTA were added into the medium biosynthesis of pigments was inhibited by 140-200 %.

 

PHYTOPATHOGENIC FUNGI

Troshina N.B., Glukhenkova M.V., Surina O.B., Maksimov I.V., Khairullin R.M. Morphological analysis of Tilletia caries growth and development on wheat calluses // Mycol. and phytopat. V. 34, N 3, 2000. P.48-56.

Abstract

It was shown, that pathogen passes through all ontogenetic stages in dual cultures of wheat Triticum aestivum and T. timopheevii with bunt agent Tilletia caries. The combined cultures obtained had features of similarity and distinction both between themselves and between host-plant - pathogen systems.

Kirik N.N., Ellanskaya I.A., Borodaj V.V. Conidial stage of Sclerotinia sclerotiorum - a pathogen causing white rot of carrots // Mycol. and phytopat. V. 34, N 3, 2000. P.56-58.

Abstract

The paper presents the report on studies of the conidial stage of Sclerotinia sclerotiorum - the pathogen of carrot (white rot). Terminal type of formation of the sclerotia is discovered.

Gagkaeva T.Yu., Levitin M.M. Identification of the pathogen causing leaf spots on apple trees in Krasnodar province orchards // Mycol. and phytopat. V. 34, N 3, 2000. P.58-63.

Abstract

The presented study was devoted to identification of species of fungal isolates causing leaf spot of apple trees in Krasnodar province. Results from microscopic observations of strains and from studying their cultural properties allowed to confirm that the fungus belongs to Alternaria alternata. Comparison of studied strains with the two samples obtained from IMI (CAB Bioscience) showed high similarity. Inoculation of apple tree leaves by conidial suspension of the Krasnodar strains resulted in appearance of necrotic spots characteristical for alternariosis. Cultural liquid with strains of high aggressiveness also caused typical symptoms of alternariosis when applied to the leaves. Presence of aggressive toxigenic isolates in Krasnodar population allows to conclude that A. alternata f. sp. mail, an infection agent causing alterariosis spots on apple tree leaves is found to appear in the region.

Buga S.F., Radyna A.A., Boyarchuk V.E. Monitoring of Fusarium nivale resistance to fundazole // Mycol. and phytopat. V. 34, N 3, 2000. P.63-68.

Abstract

Susceptibility of F. nivale population to benzimidazole group products has been monitored in a course of the five-year testfiles aimed to conserve elevated resistance and absence of cross-resistance to preparations from other groups.

Aleksandrova A.V., Velikanov L.L., Sidorova I.I., Sizova T.P. Trichoderma harzianum influence on soil micromycetes. // Mycol. and phytopat. V. 34, N 3, 2000. P.68-78

Abstract

Soil fungi from the genus Trichoderma were used successfully to protect plants from soil pathogens. However, their influence on saprotrophic organisms as well as the overall ecological safety of this method were not studied carefully enough.

Introduction of Trichoderma hanianum into soil was shown to inhibit development of damage of potatoes caused by Rhizoctonia solani. At the same time such treatment suppressed both abundance and species diversity of saprophytes in soil. Species of Zygomycetes and Ascomycetes as well as rare species were found to be the most sensitive ones.