Olive oil by-products composted in a pilot scale olive plant were characterized and assayed for their suppressive activity against different fungal plant pathogens. Some cured composts consistently reduced the in vitro growth of Verticillium dahliae and other important fungal pathogens. In two-year experiments with olive and eggplant grown in pot with soil artificially contaminated with V. dahliae microsclerotia, the incorporation of 15% (w/w) of a cured compost alone or in combination with the biofungicide TV1 (Trichoderma viridae), significantly reduced the density of microsclerotia in the soil as well as V. dahliae root infection with respect to the untreated controls. The suppressive activity of the composts seems mainly caused by the beneficial residual microbial population selected during the composting process. In fact, the efficacy of the composts decreased or disappeared when it was autoclaved before use. Several bacteria and fungi, isolated and partially characterized from these composts, showed a highly antagonistic in vitro activity against V. dahliae and other fungal pathogens. The results of our investigations indicate that composted olive by-products are very promising for applications aimed at controlling fungal pathogens of different crops in organic and integrated agriculture systems.
Suppression of Verticillium dahliae microsclerotia in the rizosphere of olive and eggplant by compost from olive oil by-products
LIMA, Giuseppe;DE CURTIS, Filippo;
2005-01-01
Abstract
Olive oil by-products composted in a pilot scale olive plant were characterized and assayed for their suppressive activity against different fungal plant pathogens. Some cured composts consistently reduced the in vitro growth of Verticillium dahliae and other important fungal pathogens. In two-year experiments with olive and eggplant grown in pot with soil artificially contaminated with V. dahliae microsclerotia, the incorporation of 15% (w/w) of a cured compost alone or in combination with the biofungicide TV1 (Trichoderma viridae), significantly reduced the density of microsclerotia in the soil as well as V. dahliae root infection with respect to the untreated controls. The suppressive activity of the composts seems mainly caused by the beneficial residual microbial population selected during the composting process. In fact, the efficacy of the composts decreased or disappeared when it was autoclaved before use. Several bacteria and fungi, isolated and partially characterized from these composts, showed a highly antagonistic in vitro activity against V. dahliae and other fungal pathogens. The results of our investigations indicate that composted olive by-products are very promising for applications aimed at controlling fungal pathogens of different crops in organic and integrated agriculture systems.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
