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This study presents the effect of biopreparations (Polyversum, Biochikol 020 PC and Biosept 33 SL) on fungal and bacterial rhizosphere and non-rhizosphere communities after seed dressing and spraying of Phaseolus vulgaris plants. The use of biopreparations has a positive effect on the communities of bacteria and fungi in soil under the cultivation of this plant. The number of cfu of the studied microorganisms in the nonrhizosphere soil was slightly lower than in the rhizosphere. Biochikol 020 PC and Biosept 33 SL increased the number of cfu of bacteria Bacillus spp. and Pseudomonas spp. and decreased the population of soil-borne fungi. Different species were isolated within the fungi and they belonged to the following genera: Altenaria, Fusarium, Rhizoctonia, Sclerotinia, Gliocladium, Penicillium and Trichoderma. The most antagonistic bacteria and fungi were obtained after introducing biopreparations Biochikol 020 PC or Biosept 33 SL. The smallest number of antagonists were found in the soil after dressing the bean seeds with Zaprawa Oxafun T and spraying the plants with fungicide Bravo Plus 500 SC and in the control combination. Besides, the applied biopreparations and fungicides had a positive effect on Pheseolus vulgaris yielding.
W badaniach określono wpływ ekstraktu z grejpfruta i fungicydu Miedzian 50 WP na zdrowotność grochu oraz na kształtowanie się populacji mikroorganizmów w ryzosferze tej rośliny. Liczba roślin wyrosłych z nasion zaprawianych Grevitem 200 SL bywa zbliżona, a nawet przewyższa, ale nie statystycznie istotnie, liczbę roślin uzyskanych po zastosowaniu fungicydu Miedzian 50 WP. Wartość indeksu porażenia roślin była najmniejsza po wykorzystaniu Grevitu 200 SL, ale statystycznie nie różniła się od tej dla Miedzianu 50 WP. Z porażonych roślin izolowano m. in. Alternaria alternata, F. culmorum, F. oxysporum, F. solani, Phoma eupyrena, Pythium irregulare, Rhizoctonia solani i Sclerotinia sclerotiorum. Z ryzosfery izolowano m. in. Alternaria alternata, Fusarium spp., Gliocladium spp., Mucor spp., Penicillium spp., R. solani, S. sclerotiorum i Trichoderma spp. Liczebność bakterii ryzosferowych w kombinacjach z Grevitem 200 SL i Miedzianem 50 WP byáa istotnie większa, aniżeli w kombinacji kontrolnej. Odwrotna zależność wystąpiła w przypadku liczebność grzybów, ale statystycznie mniej grzybów wystąpiło w kombinacji z Grevitem 200 SL. Mikroorganizmy antagonistyczne dominowały w ryzosferze roślin wyrosłych z nasion zaprawianych Grevitem 200 SL.
The studies were conducted in the years 1996 - 1998 on an experimental plot of the University of Agriculture in Lublin localised in Czesławice near Nałęczów. The subject of the studies was soybean, Polan cultivar, and their purpose was to determine the species composition of fungi infecting the roots and stem base of this plant in different stages of its growth. The studies showed that on an area of 1 m2, 61 - 70 soybean seedlings and 60 - 69 plants at anthesis grew. The proportion of infected seedlings ranged from 14.3% to 18%, while at anthesis only a small increase of the number of infected plants was observed. In the case of seed1ings, the following fungi turned out to be most harmful: P. irregulare , F. solani, R. solani and F. oxysporum f. sp. glycines. On the other hand, F. oxysporum f. sp. glycines had the greatest effect in infecting the roots and stem base of plant s at anthesis.
The purpose of the present work was to estimate the effectiveness of grapefruit extract and Pythium oligandrum in protection of common bean, runner bean and pea from soil-borne pathogenic fungi. The investigated preparations were used for seed dressing and spraying plants at the beginning of anthesis. The results pointed out that the applied products considerably improved emergence, healthiness and yielding of the examined plant species. Besides, Biosept 33 SL showed a better effect than Polyversum. Independently on the species, the fewest plants, with the greatest proportion of infected ones and the smallest yield of seeds were obtained from the untreated control. Alternaria alternata, Fusarium spp., Pythium irregulare, Rhizoctonia solani and Sclerotinia sclerotiorum were frequently isolated from infected roots and stem bases as well as from seeds of bean and pea. Fusarium oxysporum tuned out to be dominant. The proportion of the above listed fungi in the treatments with Biosept 33 SL or Polyversum was smaller than in the control. At the same time, the role of those fungi in infecting the plants of common bean, runner bean and pea treated with Biosept 33 SL was only a little smaller than after using Polyversum.
Cover crops are used in the cultivation of various plants. They properly modify the composition of soil microorganisms and can protect of plants from phytopathogens. The purpose of the field and laboratory studies was to determine the quantitative and qualitative composition of microorganisms in the soil under carrot cultivated with the use of oats, tansy phacelia and spring vetch as cover crops. The paper presents also studies on soil-borne fungi threatening the healthiness of carrot roots. In the conventional cultivation of carrot the population of bacteria (including Pseudomonas spp. and Bacillus spp.) was the smallest, while after the application of oats it was the largest. Oats and spring vetch were most effective in limiting the occurrence of soil-borne fungi. Those plants and tansy phacelia caused an increase of the population of saprotrophic fungi (Albifimbria spp., Clonostachys spp. and Trichoderma spp.) in the soil. Intercrop plants had a positive effect on the healthiness of carrot seedlings and roots. Alternaria dauci, A. alternata, A. radicina, Fusarium oxysporum, Globisporangium irregulare, Neocosmospora solani, Phytophthora sp., Rhizoctonia solani and Sclerotinia sclerotiorum proved to be the most harmful towards the studied underground parts of carrot. Oats proved to be the most effective in inhibiting the occurrence of the pathogenic fungi for Daucus carota L.
The object of a field experiment conducted in the years 2003–2004 was the rhizosphere soil of soybean ‘Mazowia’ cv. Before the sowing, the seeds were dressed with biopreparations (Biochikol 020 PC, Biosept 33 SL, Polyversum) or fungicide (Oxafun T). The non-dressed seeds constituted the control. The microbiological analysis of the rhizosphere soil of soybean, carried out at anthesis, showed that the greatest number of bacteria in total and bacteria Bacillus spp. and Pseudomonas spp. occurred after the application of Biochikol 020 PC, while the lowest occurred in the control combination. The smallest number of fungi was observed after the application of Biochikol 020 PC or Oxafun T, slightly bigger after the introduction of Biosept 33 SL or Polyversum into the soil, while the biggest in the control combination. Fungi from the genera of Alternaria, Fusarium, Pythium and Gliocladium, Penicillium, and Trichoderma were most frequently isolated from the rhizosphere of soybean. After the application of biopreparations the proportion of pathogenic fungi in the rhizosphere of soybean was much smaller than in the control. The highest proportion of Gliocladium spp. occurred after the application of Polyversum or Biochikol 020 PC, while that of Trichoderma spp. after the introduction of Biochikol 020 PC or Biosept 33 SL. Besides, tests on dishes showed that the biopreparations and the fungicide used in the experiment contributed to increased numbers of antagonistic bacteria (Bacillus spp. and Pseudomonas spp.) and fungi (Gliocladium spp. and Trichoderma spp.).
The studies were conducted in the years 1998–2000 on soybean, cv. Polan. The purpose of the studies was to conduct microbiological and mycological analyses of the leaves and pods of soybean. Bacteria and fungi were obtained much more often from the diseased soybean parts as compared to the healthy ones. 778 fungi isolates were obtained as a result of the mycological analysis of the leaves and pods of soybean. Fusarium spp. and Phomopsis sojae were most frequently isolated within pathogenic fungi. Their proportion was 17.5% and 7.8% of all the fungi, respectively. On the other hand, the isolated saprophytic fungi included for example the species from the genera of Acremonium, Cladosporium, Gliocladium, Penicillium and Trichoderma as well as Aureobasidium pullulans and Epicoccum purpurascens. Besides, about a four times lower number of antagonistic microorganisms (Bacillus spp., Pseudomonas spp., Gliocladium spp., Penicillium spp., Trichoderma spp.) was isolated from the infected soybean parts in comparison to the number of microorganisms isolated from the healthy parts.
The purpose of the studies conducted in the years 1996-1998 was to determine the quantitative and qualitative composition of bacterial and fungal communities in rhizosphere of soybean cultivated in monoculture and non-rhizosphere soil. Besides, the proportion of bacteria and fungi, which were distinguished by their antagonistic effect towards soil-borne pathogens was established. A microbiological analysis of 1g of dry weight of soil from rhizosphere of soybean resulted in 3.21 x 10⁶ to 8.70 x 10⁶ bacterial colonies and from 70.51 x 10³ to 123.74 x 10³ fungal colonies. In the case of non-rhizosphere soil, 3.50 x 10⁶ to 4.75 x 10⁶ bacterial colonies and 16.16 x 10³ to 51.38 x 10³ fungal colonies were obtained. Besides, soybean cultivation in monoculture had a negative effect on the number of antagonistic isolates of bacteria (Bacillus spp., Pseudomonas spp.) and fungi (Gliocladium spp., Penicillium spp., Trichoderma spp.). Smaller numbers of antagonistic bacteria and fungi in rhizosphere soil of soybean cultivated in monoculture as compared to non-rhizosphere soil, can prove little biological activity, which results in a worse phytosanitaty condition of the soil.
The purpose of the studies conducted in the years 1996-1998 was to determine the quantitative composition of bacteria and fungi populations in the rhizosphere of spring wheat, winter wheat, potato and soybean, and in non-rhizosphere soil. Besides, the effect of root exudates of these plants on the formation of antagonistic microorganisms is presented. A microbiological analysis found out that 1 g of rhizosphere soil dry weight of the examined plants and non-rhizosphere soil contained from 4.24 x 10⁶ to 5.97 x 10⁶ bacteria colonies on average. The lowest number of bacteria was found in non-rhizosphere soil (4.24 x 10⁶ on average), and the highest in rhizosphere of potato (5.97 x 10⁶ on average). The fewest fungi colonies (28.59 x 10³ on average) were isolated from 1 g of dry weight of winter wheat rhizosphere, and the most (93.41 x 10³) from soybean rhizosphere. Antagonistic bacteria of genera Bacillus and Pseudomonas, and fungi of Gliocladium, Penicillium and Trichoderma genera dominated in winter wheat rhizosphere. Soybean roots exuded the greatest number of aminoacids (1.088 mg/ml of the solution), while spring wheat roots exuded the smallest amount (0.148 mg/ml of the solution). The percentage of aromatic and alkaline aminoacids was the lowest in potato root exudates, whilc the highest was found out in the exudates of winter wheat.
A field experiment was conducted in the years 2003-2004 on a field of 10-years’ soybean monoculture, with naturally accumulated infection material in the soil. Soybean of ‘Mazovia’ was the object of studies. Before the sowing the seeds were dressed, and at the beginning of anthesis the plants were sprayed with biopreparations Polyversum, Biosept 33 SL and Biochikol 020 PC. The experiment considered the combination with dressing the seeds by means of Zaprawa Oxafun T (a.s. carboxine 37.5% + tiuram 37.5%) and spraying the plants with fungicide Bravo Plus 500 S.C. (a.s.: chlorotalonile 50%). The seeds that were not dressed constituted the control. During the vegetation the number and healthiness of soybean plants were determined twice (in the seedling phase and at anthesis), at the same time a laboratory mycological analysis was carried out. After the harvest the studies established the size and quality of the seed yield of soybean growing in particular experimental combinations. The best number of plants was obtained in the combination with Biosept 33 SL, slightly weaker after applying Polyversum or Zaprawa Oxafun T, and the worst in the control combination. Biosept 33 SL and the fungicide were the most effective in protecting the plants from infection by soil-borne fungi. Polyversum and Biochikol 020 PC also showed a good protective effect. The greatest seed yield was collected from soybean plants after applying Biosept 33 SL, while the lowest – from control plants. Soybean plants were mainly infected by Fusarium spp.,A. alternate, P. exigua, R. solani and P. irregulare. Those fungi were most frequently isolated from control plants, and the least frequently after applying Biosept 33 SL or Polyversum. The proportion of pathogenic fungi (P. sojae, Fusarium spp., S. sclerotiorum, P. exigua) in seed infection of soybean was the smallest in the combinations with Biosept 33 SL or Zaprawa Oxafun T, while the biggest in the control.
The composition of populations of soil microorganisms depends on a number of factors, for example the species of intercrop ground cover plants. The purpose of the studies was to determine the quantitative and qualitative composition of the populations of soil microorganisms in the cultivation of carrot considering different manners of soil cul-tivation and with the use of oat, spring vetch and tansy phacelia as intercrop ground cover crops. The greatest population of total bacteria occurred in the soil where oat was the ground cover plants. The most of total fungi was observed in the control. The application of ground cover plants contributed to an increased number of antagonistic Bacillus spp., Pseudomonas spp., Gliocladium spp., Penicillium spp. and Trichoderma spp. The tillage system had no significant effect on the population of microorganisms in the soil.
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