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The effect of heavy metal ions (Cd, Cr³⁺, Cu², Ni, Pb²⁺ and Zn) on the growth and germination of conidia of the aphid pathogenic fungus Pandora neoaphidis was studied. The metal ions were added into the culture medium in three concentrations: A – concentration corresponding to the mean content of that metal in Polish soils, B – concentration 10-times higher and C – 100-times higher than the mean ones. The investigated heavy metal ions, except for Ni, added to the media at the concentrations corresponding to the mean content of these metals in Polish soils, did not affect the growth of aphid-pathogenic fungus Pandora neoaphidis. Ni, Cu, Zn and Cr, added to the media at a concentration 100-times higher than in Polish soils, prevented the growth of the pathogen. All the tested metal ions, except for Cu, added to the media at the mean soil concentration, did not affect conidial germination of the fungus. The conidia of P. neoaphidis were unable to germinate in the presence of the Cr, Cu, Pb and Zn ions in the medium at a concentration that was 100-times higher than the mean one. Cu and Zn caused a significant reduction of conidial germination even at a concentration that was 10-times higher than the mean content of these metals in Polish soils. This work suggest that strong pollution of soil by some heavy metals could be a restrictive factor of development and pathogenicty of entomophthoralean fungi in the environment.
The aim of this study was to determine in vitro effects of selected pesticides on the growth of fungi: Hirsutella nodulosa, H. brownorum, H. kirchneri and H. necatrix, isolated from phytophagous mites. Insecticides and herbicide were added to the medium at the following rates: 0.1; 1 and 10 times the field rate recommended by manufacturer. Fungicides were applied at the following rates: 0.01, 0.1 and 1 times the rate recommended by manufacturer. Pesticides tested in this experiment showed a strong inhibiting effects on the growth of fungi from Hirsutella genus – naturalpathogens of phytophagous mites. Among allpesticides tested, fungicides showed the strongest inhibiting effect on the growth of Hirsutella species and especially flusilazole (Punch 400 EC). Amitraz (Mitac 20 EC) and phosalone (Zolone 350 EC) were the most toxic among tested insecticides. Fungi H. necatrix and H. kirchneri isolated from eriophyid mite Abacarus hystrix were the most resistant to toxic effect of tested pesticides but H. nodulosa isolated from Tarsonemidae mite seems to be the most susceptible.
Celem pracy było określenie wpływu zastosowania podłoża popieczarkowego (grzybni pochodzącej z hodowli pieczarek) w nawożeniu gleb uprawnych na zawartość fosforu przyswajalnego oraz aktywność fosfatazy kwaśnej i alkalicznej. Doświadczenie wegetacyjne przeprowadzono na polu produkcyjnym indywidualnego gospodarstwa rolnego, w miejscowości Zając (Wysoczyzna Siedlecka), w latach 2008 i 2009. Na podstawie przeprowadzonych analiz stwierdzono, iż zastosowanie podłoża popieczarkowego w nawożeniu gleb wpłynęło na zwiększenie udziału fosforu w formach przyswajalnych, w stosunku do obiektu bez nawożenia, a aktywność fosfatazy kwaśnej w poziomie próchnicznym gleby poszczególnych obiektów doświadczenia była większa od aktywności fosfatazy alkalicznej i zależała istotnie od lat trwania doświadczenia oraz zastosowanego nawożenia.
The aim of this study was to compare the species composition and the intensity of entomopathogenic fungi occurrence in the soil from mid-field woodlots and adjacent small farmlands. The study material consisted of soil samples taken from a mid-field woodlot and an adjacent small-scale arable field in three different localities in the vicinity of Siedlce. Entomopathogenic fungi were isolated from soil using two methods: the insect bait method and the selective medium. The comparative study showed that the soil from mid-field woodlots was characterized by a richer species composition of entomopathogenic fungi than of adjacent arable fields. A total of six fungal species representing the anamorphs of Hypocreales (Ascomycota) were isolated from the soil collected from mid-field woodlots: B. bassiana, B. brongniartii, M. anisopliae, M. flavoviride, I. farinosa and I. fumosorosea. The presence of only three species was reported in the farmland soil: B. bassiana, M. anisopliae and I. fumosorosea. This fact confirms the important role of semi-natural habitats as a source of biodiversity of entomopathogenic fungi in agricultural landscape. It was found that entomopathogenic fungi together formed more colony-forming units in the soil from arable fields than that of neighbouring mid-field woodlots. B. bassiana was the species of fungus which infected more bait insect larvae and formed significantly more colony-forming units (CFU) in the soil from mid-field woodlots than that of farmland in the localities studied, whereas the trend was the opposite in the case of I. fumosorosea and M. anisopliae. Given the presence of entomopathogenic fungi in the farmland soil in the three test places together, it was found that I. fumosorosea was dominant in the soil from the two arable fields, where this fungus infected more G. mellonella larvae and formed significantly more CFUs than the other species of fungi. M. anisopliae was the second most frequently isolated farmland species.
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