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W doświadczeniu przeprowadzonym w latach 2003 i 2004 na poletkach doświadczalnych w Tomaszkowie na glebie kompleksu żytniego słabego (6) w układzie losowanych podbloków, w trzech powtórzeniach uprawiano trzy odmiany ziemniaka jadalnego: bardzo wczesną Bard oraz średnio wczesne Irga i Tara. W badaniach uwzględniono zaprawianie chemiczne sadzeniaków na mokro, przeprowadzone wiosną preparatami zalecanymi przez IOR w Poznaniu do ochrony przed rizoktoniozą: Dithane M 45 75 WG w dawce 200 g·100 kg⁻¹ bulw i Vitavax 2000 FS w dawce 300 ml·100 kg⁻¹ bulw). Kontrolę stanowiły bulwy niezaprawiane. W laboratorium dokonano izolacji grzybów z gleby. Odmiany ziemniaka i preparaty chemiczne użyte do zaprawiania bulw kształtowały skład ilościowy i jakościowy zbiorowiska grzybów w środowisku glebowym ziemniaka. Najwięcej grzybów zasiedlało glebę pod uprawą odmiany Irga (38,4% ogółu izolatów), a jednakową liczebność grzybów otrzymano z gleby pod pozostałymi odmianami. Udział grzybów patogenicznych w analizowanym zbiorowisku wynosił 24,6%, a wśród nich najczęściej identyfikowano gatunki Alternaria alternata i Colletotrichum coccodes (po 8% ogółu izolatów). Zaprawianie wiosenne bulw preparatem Dithane M 45 75 WG i Vitavax 2000 FS redukowało liczebność grzybów glebowych kolejno o 18,5 i 13% w porównaniu z kontrolą. Jednocześnie u wszystkich badanych odmian w kombinacji z chemicznym zaprawianiem stwierdzono ograniczenie populacji patogenów w środowisku glebowym, a ich udział wynosił od 5 do 8% wszystkich wyosobnień, podówczas gdy w kontroli stanowiły one 12%.
Fungal communities colonizing the stems of three potato cultivars fertilized with Basfoliar 12-4-6, ADOB Mn, and Solubor DF were analyzed in the present study. The response of eight fungal potato pathogens (Alternaria altérnala, Colletotrichum coccodes, Fusarium concolor, F. culmorum, F. oxysporum, F. solani, Helminthosporium solani, and Rhizoctonia solani) to the above foliar fertilizers added to the PDA medium at the following concentrations: 10, 100, 500, 1,000, and 10,000 mg‧dm-3 was determined during in vitro tests. The predominant fungal species isolated from potato stems were Colletotrichum coccodes (Basfoliar 12- 4-6 treatment and control treatment) and Alternaría altérnala (ADOB Mn and Solubor applied in combination). Fungi showing antagonistic activity against pathogens had a low share of the ftmgal community. Foliar fertilizers added to the PDA medium at the studied concentrations significantly inhibited the mycelial growth of A. altérnala, C. coccodes, F. solani, and R. solani. F. concolor, F. culmorum, H. solani, and F. oxysporum grown on the PDA medium containing ADOB Mn were least sensitive to the applied fertilizers. Solubor DF had the most toxic effect on fungal pathogens - when applied at the highest concentration, it almost completely suppressed the mycelial growth of pathogenic fungi, except for A. alternala and F. concolor.
The aim of the laboratory experiment was the isolation of fungi colonized patato tubers directly (immediately) after harvest and after 5-month storage. 67 potato tubers samples collected in 1998 and 1999 from the areas of province Warmia and Mazury were examined. The occurrence of 36 and 46 species were confirmed on analyzed tubers after harvest and storage, respectively. The most frequent species which occurred on tubers were: Alternaria alternata (9.4%), Colletotrichum coccodes (12.6%), Rhizoctonia solani (7.4%) and fungi from Fusarium genera (8.7% ).This fugi, except Rhizoctonia solani, more often colonized potato tubers after storage. Among saprofitic fungi most frequent were: Epicoccum (3.4%), Mortierella .1%), Mucor(6.0%), Penicillium (17.0%), Rhizopus (7.1 %) and Trichoderma (12.9%). More colonies of fungi were obtained from potato tubers analyzed after harvest. Remaining fungi were more frequently isolated after storage.
The experimental materials comprised the fruits of tomato cv. Robin F1 and red pepper cv. Mira harvested from plants sprayed three times with the growth regulator Asahi SL, the biostimulator Biochikol 020 PC, the biocontrol agent Polyversum, and the fungicide Bravo 500 SC. Control plants were sprayed with sterile water. Total fruit yield, average fruit weight, and the concentrations of total extract, pectin, reducing sugars, carotenoids, and phenolic compounds were determined. Biological and fungicidal control contributed to an increase in the yield and average weight of tomato and pepper fruit. The protective treatments had no effect on the content of extract and reducing sugars in tomato and red pepper fruit. The applied biological and fungicidal control agents were negatively correlated with the concentrations of carotenoids and phenolic compounds in tomato fruit, and positively with the pectin content of tomato and red pepper fruit.
Three potato cultivars, Adam (early), Rudawa (late) and Skawa (late), were grown in a threeyear experiment in Bałcyny. The severity of late blight and early blight was evaluated using a ninedegree scale during the growing season, as dependent on applied foliar fertilizers: ADOB Mn, Basfoliar 12-4-6 and Solubor DF (applied alone and in combinations). The results, presented as the infection index, were analyzed statistically (STATISTICA ® 8.0 2007–2008). Infection degree was affected by potato cultivar and weather conditions. The highest symptoms of late blight were noted in wet seasons of 2007 and 2009, and the most affected cultivar was Adam. Early blight developed in 2008, characterized by moderate atmospheric precipitation, on late cultivars and on cv. Adam in the last two years. Foliar fertilization had no significant effect on potato infections caused by Phytophthora infestans and Alternaria spp., as confirmed by the average infection index determined for the tested cultivars in each year. The most severe symptoms of late blight were observed in the treatment with ADOB Mn in 2007, and of early blight – in the treatment with ADOB Mn and Solubor DF in 2008. The slightest symptoms of late blight were noted on non-fertilized plants in 2008, and of early blight – on plants fertilized with Basfoliar 12-4-6 in 2007.
The paper presents the results of a three-year exact experiment conducted in Bałcyny, in which a late potato cultivar, Jasia, was grown. The objective of the study was to determine the effect of different levels of mineral fertilization: A (N 80 kg 􀂉 ha-1 P 80 kg 􀂉 ha-1 K120 kg 􀂉 ha-1) and B (N 120 kg 􀂉 ha-1 P 144 kg 􀂉 ha-1 K156 kg 􀂉 ha-1), and foliar fertilization (Basfoliar 12-4-6, ADOB Mn and Solubor DF) on the quantitative and qualitative composition of fungal populations colonizing potato tubers. Fungi were isolated immediately after harvest and after a five-month storage period. After seven days of incubation, fungal colonies were transferred onto agar slants for microscopic identification. Over the entire experimental period, more pathogenic fungi were obtained from potato tubers analyzed after storage (62.9% of the total fungal population after storage) than from those analyzed immediately after harvest (39.1%), and the greatest number of fungi was reported in 2004. Rhizoctonia solani was isolated most frequently, followed by Colletotrichum coccodes and Alternaria alternata. Pathogens of the genus Fusarium and the species Helminthosporium solani were not numerous. In the treatment A with soil mineral fertilization with lower NPK rates, larger numbers of pathogenic fungi were noted in 2004 after harvest and after five-month storage, and in 2005 after harvest. At the remaining dates of analysis, pathogens were more frequently isolated from potato tubers in experimental variant B with higher NPK rates. Immediately after harvest, the highest number of pathogenic fungi was isolated in the treatment with foliar application of ADOB Mn and Basfoliar 12-4-6. After five-month storage, pathogens most often colonized potato tubers in experimental variant B with foliar application of Solubor DF, Solubor DF and ADOB Mn, and in experimental variant A with a combination of fertilizers. In the other fertilization variants, including in the control treatment, the population size of pathogenic agents remained at a similar level.
Badania przeprowadzono w latach 2007-2009 na poletkach doświadczalnych w Bałcynach. Uprawiano trzy odmiany ziemniaka jadalnego: wczesną Adam oraz późne Rudawa i Skawa. Doświadczenie obejmowało następujące kombinacje nawożenia dolistnego: A. Basfoliar 12-4-6 (8 dm³·ha⁻¹), B. ADOB Mn (4 dm³·ha⁻¹), C. Solubor DF (2 dm³·ha⁻¹), D. ADOB Mn (2 dm³·ha⁻¹) + Solubor DF (1 dm³·ha⁻¹), E. ADOB Mn (2 dm³·ha⁻¹) + Basfoliar 12-4-6 (4 dm³·ha⁻¹), F. Basfoliar 12-4-6 (4 dm³·ha⁻¹) + Solubor DF (1 dm³·ha⁻¹), G. Basfoliar 12-4-6 (2,7 dm³·ha⁻¹) + ADOB Mn (1,3 dm³·ha⁻¹) + Solubor DF (0,7 dm³·ha⁻¹), H. kontrola bez nawożenia dolistnego. Aplikację nawozów dolistnych wykonano jednorazowo w fazie pełnego zwarcia międzyrzędzi ziemniaka. W doświadczeniu rozpatrywano zdrowotność bulw ziemniaka po sześciu tygodniach przechowywania. Zarazę ziemniaka szacowano w 5 kg próbie bulw, podając % masy porażonych bulw. Parch zwykły i ospowatość bulw oceniano na 100 bulwach pobranych z poszczególnych poletek, składających się na kombinację według 9-stopniowej skali. Wyniki przedstawiono w % jako indeksy porażenia. Wyniki opracowano statystycznie (STATISTICA ® 8.0 2007-2008). Nasilenie objawów omawianych chorób było większe na bulwach pochodzących ze zbiorów w 2007 i 2009 roku niż w 2008. Zaraza ziemniaka wystąpiła na bulwach w małym nasileniu, a najwyższy procent chorych bulw - 2,5 zanotowano w 2007 r. na odmianie Adam w kombinacji kontrolnej oraz w kombinacji z zastosowanym nawozem Solubor DF. Odmiana Adam i Rudawa charakteryzowały się istotnie wyższym porażeniem przez Streptomyces scabies w porównaniu do odmiany Skawa. Najsilniejsze objawy parcha zwykłego stwierdzono na bulwach wszystkich odmian w kombinacji bez nawożenia, z istotną różnicą między średnimi indeksów porażenia tylko u odmiany Rudawa. Objawy ospowatości, co potwierdza analiza średnich z okresu badawczego, częściej obserwowano na bulwach wyrosłych z roślin nienawożonych lub nawożonych pojedynczo nawozami. Największe ograniczenie porażenia przez Rhizoctonia solani stwierdzono na bulwach badanych odmian w kombinacji z łącznie aplikowanymi trzema nawozami.
W badaniach zanalizowano wpływ dolistnego nawożenia ziemniaka na strukturę zbiorowisk grzybów zasiedlających bulwy po zbiorze i 5-miesięcznym przechowywaniu. Materiał badawczy stanowiły bulwy trzech odmian ziemniaka jadalnego: wczesnej Adam, późnych: Rudawa i Skawa, pochodzące ze zbiorów z poletek doświadczalnych w Bałcynach w latach 2007-2009. Zastosowano następujące nawozy: Basfoliar 12-4-6, ADOB Mn i Solubor DF, pojedynczo i w kombinacjach. Hodowlę grzybów prowadzono na podłożu PDA, a kolonie wyrosłe po okresie inkubacji przeszczepiano na skosy agarowe w celu identyfikacji mikroskopowej. Wyniki opracowano statystycznie (STATISTICA ® 8.Ü 2008). Z bulw ziemniaka analizowanych po zbiorze otrzymano mniej grzybów niż po przechowywaniu. W obydwu zbiorowiskach najliczniej izolowano gatunki rodzaju Penicillium oraz grzyby patogeniczne, z największym udziałem Colletotrichum coccodes i Rhizoctonia solani. Ten ostatni gatunek najczęściej zasiedlał bulwy pochodzące ze zbioru w ostatnim roku badań (19,7 i 27,5% kolejno po zbiorze i przechowywaniu). Wśród pozostałych sprawców chorób mniej licznie występowały gatunki rodzaju Altemaria i Fusarium, a sporadycznie Helminthosporium solani. Bogatsze zbiorowiska patogenów zanotowano na odmianie Adam niż na pozostałych odmianach. Stwierdzono tendencję ograniczającego wpływu nawozów dolistnych aplikowanych łącznie, z wyjątkiem kombinacji „D” - ADOB Mn + Solubor DF na liczebność patogenów zasiedlających bulwy niż nawozów aplikowanych pojedynczo czy w kombinacji kontrolnej.
An exact micro-plot experiment was conducted to determine the effect of fungicides (treatments: Sandofan Manco 64 WP, Penncozeb 80 WP, Tanos 50 WG; Tanos 50 WG applied three times; Tanos 50 WG, Penncozeb 80 WP, Tanos 50 WG) on the severity of late blight and early blight in three potato cultivars and on the composition of fugal communities colonizing potato leaves. The tested fungicides significantly reduced the intensity of late blight and early blight. The efficacy of fungicidal control was affected by weather conditions and potato cultivars. The highest efficacy (30–36%) against late blight and early blight was noted in potato plants cv. Aster sprayed with Sandofan Manco 75 WG, Penncozeb 80 WP, Tanos 50 WG and Tanos 50 WG applied three times in the first year of the study. Sandofan Manco 75 WG, Penncozeb 80 WP, Tanos 50 WG, and Tanos 50 WG and Penncozeb WP 80 used alternately during the last two last growing seasons were most effective in late blight control in potato cv. Tara and Salto. In these cultivars, early blight was best controlled with Tanos 50 WG applied three times, and Tanos 50 WG and Penncozeb 80 WP used alternately. The lowest counts of Alternaria spp. – the causal agent of early blight – were isolated from potato leaves in the above treatments.
Late blight (Phytophthora infestans /Mont./ de Bary) and early blight of potato (Alternaria solani Sorauer, A. alternata /Fr./ Keissler) belong to very severe potato diseases, which are able to decimate potato plantations in Poland and worldwide. In a strict plot experiment, run from 2008 to 2010, the severity of late blight (Phytophthora infestans) and early blight (Alternaria spp.) was determined, during the growing season, on three potato cultivars: medium-early cv. Adam, medium-late cv. Pasja Pomorska and late cv. OElêza, which received NPK soil fertilization (two fertilization levels) and foliar nutrition consisting of complex fertilizers with micronutrients (Basfoliar 12-4-6, ADOB Mn, Solubor DF). The extent to which the pathogens infected potato plants was evaluated twice during each growing season, on a 9-degree scale (PIETKIEWICZ 1985), and the results (means from two observations) expressed as a percentage represented an infestation index. During the first two seasons, the late blight symptoms were significantly less severe on the late and medium- late rather than on the medium-early cultivar. In the last year, the cultivars Adam and OElêza proved to be the least infected by P. infestans. Differences in the intensity of early blight of potato on the examined potato cultivars appeared in the third year, when cv. Adam proved to be the healthiest variety. Some non-significant differences were demonstrated in the severity of the diseases depending on the applied foliar fertilization and the levels of NPK fertilization.
In an exact micro-plot experiment, potato plants of three cultivars were sprayed at 10-day intervals with the following fungicides: Sandofan Manco 64 WP, Penncozeb 80 WP and Tanos 50 WG; Tanos 50 WG applied three times; Tanos 50 WG, Penncozeb 80 WP and Tanos 50 WG (control treatment without fungicides). After five-month storage, the incidence of common scab (Streptomyces scabies) was determined on 100 tubers selected randomly of particular treatments, according to a nine-point scale (percentage infection index). The symptoms of late blight (Phytophthora infestans) and dry rot (Fusarium spp.) were evaluated in 5 kg samples for each treatment (percentage of the mass of infected tubers). Fungi were isolated from tubers at the laboratory. The applied fungicidal control insignificantly affected the severity of infection caused by S. scabies only in the last year of the study. Potato tubers from fungicide-treated plants showed weaker symptoms of infections caused by P. infestans and fungi of the genus Fusarium. The abundance of pathogens colonizing potato tubers was lower in fungicide treatments.
Macro- and microelements have an effect on the process of photosynthesis and transpiration. Foliar fertilizers increase the content of elements in leaves and affect the course of gas exchange. This work have presented the results of the study aimed to estimate the effect of soil (NPK 280 and 420 kg·haˉ¹ ) and foliar (Basfoliar® 12-4-6, ADOB® Mn, Solubor® DF) fertilizer application on the intensity of gas exchange in potato plants of semi-early to late cultivars. In the research hypothesis it was assumed that macro- and microelements contained in foliar fertilizers will affect the intensity of process of photosynthesis and transpiration in the field conditions, which in consequence may affect the yield and quality of potato tubers. Measurements of photosynthesis and transpiration were made using the portable gas analyser LI-COR 6400 (DMP AG SA LTD). Readings for gas exchange parameters were performed at several days’ intervals. The obtained high photosynthesis rate, reaching even up to 35.59 μmol CO2·mˉ²·sˉ¹ in 2010, indicated a good general state of plants. The late cultivar Ślęza has shown the highest photosynthesis rate – 18.45 μmol CO2·mˉ²·sˉ¹. No effect of differentiated rates of soil fertilizers on photosynthesis intensity was observed. In the experiment, potato cultivars and the applied rate of soil NPK fertilization of 280 kg·haˉ¹ significantly differentiated transpiration intensity. For the semi-late cultivar, the lower rate of soil fertilization resulted in a higher intensity of the process of transpiration. Transpiration proceeded more dynamically after a period of heavy rainfalls. No effect of microelements contained in foliar fertilizers on processes of gas exchange has been indicated.
Potato tubers accumulate non-starch polysaccharides. A higher level of carbophydrates is correlated with a higher amount of potato pulp and high starch losses during technological processing. During the extraction of starch from potato tubers, glycoalkaloids, free amino acids and proteins are transferred to starch milk, which increases its foaminess and hinders further processing. Another important goal is to prevent the darkening of raw potato pulp. The scarcity of research reports on the effect of fertilization on the content of soluble and insoluble non-starch polysaccharides has encouraged the authors to undertake this study. The aim of this study was to determine the effect of soil (280 and 420 kg NPK·ha⁻¹) and foliar (Basfoliar 12-4-6, ADOB Mn, Solubor DF) application of mineral fertilizers on nutrient concentrations in potato varieties. The varieties had a significant effect on the dry matter content of tubers and flesh darkening four hours after cutting. The levels of crude protein and nonstarch polysaccharides were affected by the varieties and soil fertilizer doses. The late variety had the highest dry matter content. The medium-early variety the highest content of crude protein, the lowest content of non-starch polysaccharides and a low degree of flesh darkening. Foliar fertilizers had no significant influence on the analyzed parameters. The high level of soil fertilization (420 kg NPK·ha⁻¹) contributed to an increased content of protein and carbohydrates, which makes starch extraction from potato tubers more difficult.
Eggplants, cv. Black Beauty, were grown in the greenhouse of the University of Warmia and Mazury in Olsztyn. During the growing season, the plants were sprayed three times with Asahi SL, Biochikol 020 PC and Bravo 500 SC, they were watered with Polyversum, and a mycorrhizal inoculum was applied to the roots of seedlings. Unprotected plants, treated with distilled water, served as control. After fruit harvest, samples of the substrate used for eggplant cultivation, eggplant stems and roots were collected, and fungi were isolated in the laboratory. The fungal soil community was more abundant and diverse than the communities colonizing the stems and roots of eggplants. The applied biological and chemical control agents effectively reduced the abundance of fungi, including pathogenic species, in the organs of eggplants and the substrate used for eggplant cultivation. Potential pathogens (Alternaria alternata, Botrytis cinerea and Fusarium species) were isolated in high numbers from eggplant stems in the control treatment and in the Polyversum treatment (67%). The lowest number of potential pathogenic species were isolated from plants treated with the biostimulator Asahi SL, the fungicide Bravo 500 SC and the mycorrhizal inoculum. The population size of pathogenic fungi (Colletotrichum coccodes and Fusarium ) isolated from eggplant roots was smaller, compared with stems, particularly in the treatments with the fungicide Bravo 500 SC and the biostimulator Biochikol 020 PC. The soil fungal community was dominated by yeast-like fungi (over 60% of all isolates). Fungi known as potential causal agents of diseases were found in low abundance, and they were not detected in substrate samples collected from under fungicide-treated eggplant plants.
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