Wyniki wyszukiwania - Biblioteka Nauki

1

Micromycetes, producers of toxins, detected on stored vegetables

100%

Lugauskas A. , Repeckiene J. , Novosinskas H.

Annals of Agricultural and Environmental Medicine

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2005

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tom 12

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nr 2

253-260

EN

In 2003-2004, investigations of mycological contamination of stored and newly harvested vegetables were carried out. The aim of the study was to detect fungal species able to synthesize toxic metabolites, which are spread on vegetables under various conditions. For mycological investigations, samples of carrots, onions and cabbage were taken from storehouses with different storage periods and conditions. Penicillium expansum, P. nalgiovense, Mucor silvaticus and Penicillium verrucosum were more frequently detected on carrots, Penicillium expansum - on onions and Aspergillus niger, Botrytis cinerea, Mucor hiemalis, Penicillium funiculosum and Penicillium expansum - on cabbages. Storing conditions of vegetables influenced distribution of different fungal species. Primary screening using CYA and YES test-media showed that 46.7% of tested strains may be evaluated as toxin producers. The ability of fungi to produce mycotoxins depends on their growth substrata. According to Rf and fluorescence in the UV of compounds comparing with standards, such toxins as patulin, cytochalasin and penitrem were identified. The ability of Penicillium expansum Sv-168-1 growing on different foodstuff and especially potato to produce patulin was confirmed quantitatively.

2

Microbial communities in disturbed peatlands colonized with invasive moss Campylopus introflexus (Hedw.) Brid

100%

Repeckiene J. , Salina O. , Jukoniene I.

Polish Journal of Ecology

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2012

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tom 60

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nr 3

EN

Abundance of microorganisms and their communities’ structure in disturbed peatlands characterized by different chemical properties and plants cover were studied. Naturally regenerating four disturbed peatlands from different regions of Lithuania were selected for the investigation. The aim of the study was to investigate invasive moss Campylopus introflexus cover effect on microbial communities. The peat under Eriophorum angustifolium, Polytrichum strictum and bare peat were sampled for the comparison. The abundance of microorganisms in sampling plots depends on the content of total nitrogen, potassium, soil organic matter and pH as well as on growing plants. In the peat under C. introflexus, the number of ammonifying and mineral N assimilating bacteria was significantly lower in comparison with other plants or bare peat. The results on fungi abundance in peat under C. introflexus allow to predict that the distribution of moss doesn‘t affect negatively the development of fungi. A total of 236 fungal strains belonging to 21 genera were isolated from the studied peat samples. Species from the Penicillium, Trichoderma and Mortierella genera dominated among them. The structure of microbial communities varied in separate peatlands and under various plants. However, all examined microorganism communities seemed to be able adapted to organic matter degradation.

3

The occurrence of pathogenic fungi during flax growing season in Central Lithuania

100%

Gruzdeviene E. , Brazauskiene I. , Repeckiene J. , Lugauskas A.

Journal of Plant Protection Research

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2008

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tom 48

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nr 2

255-265

EN

Experiments designed to study the variation of diversity of pathogenic fungi occurring in fibre flax agrocenosis during the growing season were conducted at the Lithuanian Institute of Agriculture Upytė Experimental Station during 1999-2002. The Upytė Experimental Station is situated in Central Lithuania. Phytopathological analyses of seed, soil and plants were done at the laboratory of the Upytė Experimental Station as well as at the Biodestructor Research Laboratory of the Institute of Botany. There were identified in the rhizosphere 9 fungal species belonging to 9 genera. On flax seedlings were identified fungi belonging to 13 genera. On flax leaves at green maturity stage was identified only Oidium lini. On flax stems at green maturity stage were identified fungi belonging to 12 genera. On mature flax stems were found fungi belonging to 15 genera. On flax seed during the experimental years were identified fungi belonging to 16 genera. The number of fungi identified on seeds varied each year, depending on the year's weather conditions during the seed ripening period. Having summarised the results, we can assert that pathogenic fungi Fusarium spp. and Colletotrichum lini, were found both on seed and plant vegetative parts during the whole assessment period. Species composition of fungi present on seed differed depending on the weather conditions. A larger number and more diverse species were found on the seed that ripened during the years with wet growing seasons (2000 and 2001) whereas the seed that ripened during dry growing seasons (1999 and 2002) was less infected with fungi. The spread of fungi on stems and leaves was also determined by the weather conditions. Many species of fungi were identified in 2001, when flax crops were lodged; stems and capsules were damaged by hail, and in 2000, when there was much rainfall.

PL

W Stacji Doświadczalnej Litewskiego Instytutu Uprawy Roli (LIUR) w Upyte w latach 1999-2002 badano zmiany różnorodności grzybów chorobotwórczych w okresie wegetacji w agrocenozie lnu. Stacja Doświadczalna w Upyte znajduje się w centralnej części Litwy. Badania fitopatologiczne przeprowadzono w Stacji Doświadczalnej LIUR w Upyte i w Laboratorium Biodestruktorów Instytutu Botaniki w Wilnie. W rizosferze lnu zidentyfikowano 9 gatunków grzybów chorobotwórczych, należących do 9 rodzajów. Na kiełkach lnu zidentyfikowano 2-13 rodzajów grzybów. Na liściach lnu w okresie zielonej dojrzałości pojawił się tylko Oidium lini. Na łodygach lnu w okresie zielonej dojrzałości zidentyfikowano 12 rodzajów, a w okresie pełnej dojrzałości - 15 rodzajów chorobotwórczych grzybów. Na nasionach lnu zidentyfikowano 6-16 rodzajów grzybów. Liczba gatunków grzybów zależała od warunków meteorologicznych w okresie dojrzewania nasion. Grzyby Fusarium spp., i Colletotrichum lini na nasionach lnu i organach wegetatywnych były identyfikowane w ciągu całej wegetacji. Zestaw gatunkowy patogenów w nasionach różnił się w różnych latach badań zależnie od dominujących warunków atmosferycznych - większa liczba i bardziej zróżnicowane gatunki rozprzestrzeniły się w warunkach większej ilości opadów i ciepłej pogody (2000 i 2001 r.), a mniejsza zidentyfikowana liczba gatunków grzybów, gdy w okresie dojrzewania nasion lnu wystąpił brak wilgotności (1999 i 2002 r.). Zestaw gatunkowy grzybów na łodygach lnu także zależał od warunków meteorologicznych w okresie wegetacji roślin. Wielka różnorodność gatunkowa grzybów była obserwowana w roku 2001, kiedy zasiewy lnu wyległy i były mechanicznie uszkodzone przez grad, a także w roku 2000, gdy obserwowano dużą ilość opadów.

4

Toxin-producing fungi on feed grains and application of yeasts for their detoxification

100%

Repeckiene J. , Levinskaite L. , Paskevicius A. , Raudoniene V.

Polish Journal of Veterinary Sciences

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2013

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tom 16

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nr 2

EN

The research deals with the contamination of feeding crops with fungi, producing mycotoxins and use of selected yeasts for detoxification. The thin-layer chromatography and ELISA methods were applied for the analysis of fungal secondary metabolites. The results showed a high rate of the grain contamination with fungi, mainly from genera Penicillium, Fusarium, Aspergillus and Alternaria. Some of the fungal strains produced 6-9 toxic compounds. The novelty of the study was the application of the yeast strains in detoxification of aflatoxins, zearalenon and deoxynivalenol in feed.

5

Problems of a longtime strawberry growing in one plot

100%

Lugauskas A. , Repeckiene J. , Uselis N. , Rasimskiene A. B.

Acta Scientiarum Polonorum. Hortorum Cultus

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2003

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tom 02

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nr 2

EN

Long term investigations revealed that cultivation of strawberries (Fragaria magna Thuill.) for 10 years continuously in one plot reduces their vitality: the number of the produced runners decreases by 41%, of leaves – by 30%, form only 28% of inflorescence, the yield reduces by 50% in comparison with strawberries grown for two years in a new plot. Evident decline in the vitality and productivity of strawberries was detected during 4th–6th years of cultivation. Unequal reaction of the tested cultivars upon the durability of cultivation was noticed; strawberries of the cultivar ‘Senga Sengana’ reacted slightly, while the ones of the cultivar ‘Nida’ – strongly. It is related with different sensibility of these cultivars towards the disease agents of root rots. It was determined that long-term cultivation of the Fragaria genus plants results in the accumulation of the parasitic fungi propagules in soil: Ascochyta fragaricola, Cercospora fragariae, Fusarium oxysporum, F. solani, Perenospora fragariae, Phytophthora cactorum, Pythium intermedium, P. ultimum, Plasmodiophora brassicae, Sclerotium rolfsii, Verticillium alboatrum. Therefore, cultivation of strawberries in the same plot for longer time increases the phytopathogenic potential of soil, and short interval (1–2 years) between planting has little significance upon it. The second reason for low productivity of strawberries cultivated for a long in one plot is soil tiredness caused by fungi, synthesising and excreting into surrounding toxic secondary metabolites, widespread in the rhizosphere, especially those belonging to the Penicillium genus: P. janthinellum, P. verruculosum var. verrucosum, P. canescens, P. spinulosum.

PL

Wieloletnie badania wykazały, że uprawa truskawki (Fragaria magna Thuill.) na jednym polu przez 10 lat spowodowała zahamowanie ich wzrostu i rozwoju. Uprawiane w ten sposób truskawki tworzą o 41% mniej rozłogów, o 30% mniej liści, o 28% mniej kwiatostanów oraz tworzą o 50% mniej owoców w porównaniu z truskawką uprawianą przez dwa lata na danym polu. Najczęściej do obniżenia wzrostu i plonowania truskawki dochodzi w 4–6 roku uprawy. Nie wszystkie uprawiane odmiany reagują jednakowo obniżeniem wzrostu i plonowania. Najmniej podatną na choroby korzeni jest odmiana ‘Senga Sengana’, natomiast bardziej podatna okazała się odmiana ‘Nida’. Stwierdzono, że długotrwała uprawa truskawki powoduje wzrost potencjału infekcyjnego gleby, co związane jest ze wzrostem jednostek propagacyjnych takich grzybów chorobotwórczych, jak Ascochyta fragaricola, Cercospora fragariae, Fusarium oxysporum, F. solani, Peronospora fragariae, Phytophthora cactorum, Pythium intermedium, P. ultimum, Plasmodiophora brassicae, Sclerotium rolfsii, Verticillium albo-atrum. W wyniku prowadzonych badań wykazano, że 1-2 letnia przerwa w uprawie truskawki nie ma większego wpływu na wzrost i plonowanie oraz porażenie roślin truskawki przez fitopatogeny. Ponadto przy długotrwałej uprawie truskawki na tym samym polu zwiększa się liczebność grzybów z rodzaju Penicillium: P. janthinellum, P. verruculosum, P. canescens, P. spinulosum. Przypuszcza się, że grzyby te w strefie korzeniowej roślin tworzą związki fitotoksyczne będące produktami ich metabolizmu.

6

Effect of complex technological means on biodegradation of oil products and succession of microorganisms in polluted soil

75%

Repeckiene J. , Salina O. , Paskevicius A. , Liuzinas R. , Jankevicius K. , Bridziuviene D.

Polish Journal of Environmental Studies

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2013

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tom 22

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nr 3

EN

The impact of various technological means (addition of NPK, sewage sludge, and biopreparation) on oil product degradation was studied ex situ in biodegradation sites. The degradation degree of oil products depended on pollutant concentration and addition of fertilizers. The succession of microorganisms during biodegradation process in polluted soil was ascertained. The addition of NPK stimulated the growth of ammonifying bacteria and fungi, while sewage sludge promoted the growth of ammonificators and yeasts but suppressed fungi. The increase of OO bacteria positively correlated with the abundance of heterotrophic bacteria, while the amounts of OO yeast and fungi correlated negatively. It was demonstrated that sewage sludge is a suitable organic fertilizer for polluted soil bioremediation and, moreover, in this way the problem of this industrial waste utilization could be solved as well.