compost tea preferentially utilised the nutrients required for the germination of conidia. This prevented the formation of a germ tube and led to the lysis of Choanephora cucurbitarum conidia (Siddiqui et al. 2009). Recent findings by Sang and Kim (2011) demonstrated that, all the tested compost water extracts significantly inhibited in vitro conidial germination and appressorium formation of Colletotrichum coccodes and C. orbiculare, the causal pathogens of anthracnoses on pepper and cucumber. Kone´ et al. (2010) indicated that specific microorganisms (potential biological control agents) present in the compost tea would be more vital in the suppressive effect than the high total counts of bacteria. The beneficial microorganisms present in microbial-enriched compost tea that belong to different functional groups, such as Bacillus, Pseudomonas, lactic acid bacteria, actinomycetes and fungi (predominantly Trichoderma spp and Penicillium spp.) (Naidu et al. 2010)might have contributed to the conidial inhibition and disease suppression in the current study.
Previous findings by Siddiqui et al. (2009) found that mycelium of Choanephora cucurbitarum treated with non-sterilised CT showed alterations in mycelia morphology and lysis under light microscopy which resulted in the 100 % inhibition of mycelia growth. Observation under light microscopy in the present work identified ruptured G. cichoracearum DC. conidia that had been treated with microbial-enriched compost tea, which resulted in increased cell permeability and leakage of cellular contents. Mechanism of action underlying behind this observation could be through antibiosis. Antibiosis, which is a mechanism in which toxic metabolites penetrate the cell and inhibit cellular activity, may have caused these cytotoxic effects (Baker and Cook 1982).