Ograniczanie wyników

Czasopisma help
Autorzy help
Lata help
Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 29

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 2 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  Metarhizium anisopliae
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 2 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
Entomopathogenic fungi attack the host insect and therefore may be potentially used for insect control. Penetration of cuticle is achieved by a combination of mechanical pressure and enzymatic degradation. The entomopathogenic fungi produce a variety of exocellular hydrolytic enzymes: proteases, chitinases and lipases, which are capable to digest the major components of insect cuticle. This review describes the characteristics of these enzymes and their role in pathogenesis.
The study was aimed at estimating species composition and abundance of entomopathogenic fungi in the Chojnowski Landscape park. The effect of site, season (spring, summer, autumn) and temperature on the frequency of isolation of entomopathogenic fungi was also analysed. The effect of the first two factors was estimated based on the analysis of soil samples taken from meadow 1, forest 1 and orchard in spring, summer and autumn 2010. Three species of entomopathogenic fungi (Beauveria bassiana, Metarhizium anisopliae and Isaria fumosorosea) were isolated in the study area. Site and temperature affected the frequency of isolation of particular species. On meadow 1 and in orchard M. anisopliae appeared to be the dominating species while forest 1 was dominated by B. bassiana. From among meadow and forest sites sampled in the autumn, forest 3 (nature reserve) was characterised by the highest density of entomopathogenic fungi. M. anisopliae and B. bassiana were most often isolated from meadow sites while B. bassiana and I. fumosorosea - from forest sites. B. bassiana and I. fumosorosea infected insects with significantly higher frequency at 20°C than at 25°C.
Effectivenes of infestation B. germanica L. with strains of M. anisopliae originating from different regions of Poland. The tested strains have caused high mortality of the test insect. Especially effective in reduction were strains Browsk and Pruszyn, which even at relatively low spore density caused high mortality of examinated insects.
The entomopathogenic fungus conidia viability and sporulation may be affected by different environmental factors or by bio-pesticides and chemical products used to protect cultivated plants. In this research, we investigated the compatibility of Metarhizium anisopliae DEMI 001 isolates with three insecticides: fipronil, pyriproxyfen and hexaflumuron. The effect of fipronil, pyriproxyfen and hexaflumuron on sporulation, vegetative growth and conidial germination of the fungus was studied based on measuring the vegetative growth and sporulation. SDA medium was mixed with fipronil (10, 40 and 120 ppm), pyriproxyfen (10, 500 and 1 000 ppm), hexaflumuron (20, 50 and 120 ppm). SAD medium excluding insecticides was designated as blank. To determine the sporulation rate, spores was counted on surface area and vegetative growth was measured on the basis of colony diameter. The results showed that hexaflumuron at the concentration of 120 ppm reduced the vegetative growth to 0% showing the highest reduction effect compared to pyriproxyfen (24.59%) and fipronil (24.31%). All three insecticides reduced drastically the conidial germination at the highest concentrations (0-15%). Hexaflumuron treatment with 0% germination at all three concentrations and fipronil and pyriproxyfen with 32.36% and 9.7% germination at 200 ppm were not significantly different. Regarding the highest negative effect of hexaflumuron on germination at all three concentrations, this insecticide should not be applied together with the entomopathogenic fungus.
Study determines the species composition and frequency of entomopathogenic fungi in the soil of Jata Nature Reserve (E Poland). Fungi were isolated from soil samples by 'insect bait method' with Galleria mellonella and Tenebrio molitor larvae. We found five species of entomopathogenic fungi: Beauveria bassiana, Isaria farinosa, I. fumosorosea, Metarhizium anisopliae and Lecanicillium lecanii. The two most common species M. anisopliae and I. farinosa comprised 50.1% and 21.8% of the total number of the infected insects, respectively. Species composition of entomopathogenic fungi in the examined stands and the number of infected insects differed significantly depending on the sampling season and insect used as bait.
The soil is a habitat for many entomopathogenic fungi (EPF) all over the world. The Galleria bait method has been chosen to isolate the EPF from soil samples. The common occurrence of EPF in agricultural land was confirmed by these studies, which concluded, that the soil of Cape Verde is a habitat for EPF, such as Beauveria bassiana and Metarhizium anisopliae. The presence of B. bassiana was recorded in the cultivable land of the island of Fogo, while M. anisopliae occurred in the soil of Fogo as well as Santiago. There were no records of EPF in woodlands. Statistically, more soil samples containing B. bassiana were derived from perennial crops. The amount of sand in the soil determined the presence of the fungus. On the other hand, M. anisopliae was present on less inclined grounds. Fusarium spp. was present in half of the examined soil samples. The isolation of native EPF and their subsequent application in developing countries may significantly contribute to reduce pest populations in agriculture effectively.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 2 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.