09-08-2013, 03:58 PM
In vitro response of fungicides to pathogen Verticillium fungicola (Preuss) Hasse. and host mushroom Agaricus bisporus (Lange) Imbach
ABSTRACT
Under in vitro studies, ten fungitoxicants were evaluated at different concentrations against Verticillium fungicola by conidial germination and poisoned food techniques and against A. bisporus by poisoned food technique only. The aim of this study is to determine some effective fungicides for the control of Verticillium fungicola causing dry bubble disease of white button mushroom (Agaricus bisporus). Carbendazim proved highly fungitoxic to the mycelial growth and conidial germination of the pathogen. The other fungitoxicants in inhibiting the mycelial growth of the pathogen in order of their efficacy were myclobutanil, thiophanate methyl, difenaconazole, bitertanol, chlorothalonil, mancozeb, copper oxychloride, propineb and captan, whereas, the fungitoxicants most effective in inhibiting the conidial germination of pathogen in order of their efficacy were thiophanate methyl, myclobutanil, bitertanol, chlorothalonil, difenaconozole, copper oxychloride, mancozeb, propineb and captan. All the test fungitoxicants completely inhibited the test pathogen at 500 µg ml-1except, mancozeb, propineb and captan. The fungitoxicants were also evaluated against the host fungus (A. bisporus) at various concentrations. Amongst these, myclobutanil gave maximum inhibition of 66.60 per cent, followed by thiophanate methyl, difenaconazole, bitertanol, chlorothalonil, carbendazim, copper oxychloride, mancozeb, captan and propineb, respectively.