Screening of antagonistic activity of selected microorganisms against apple rot pathogens

Abstract

Biological control of plant pathogens is considered an attractive alternative to chemical-based treatments because it has a minimal impact on the environment. In this study, in vitro antifungal efficiency of four microorganisms (Streptomyces hygroscopicus, Saccharomyces cervisae, Bacillus cereus and Leuconostoc mesenteroides) against causal agents of apple fruit rot, was investigated. Isolates of Colletotrichum acutatum, Colletotrichum gloeosporioides and Fusarium avenaceum were obtained from apple fruit samples expressing rot symptoms. Apple samples were collected during 2012 from Ultra Low Oxygen storages in Vojvodina Province, Serbia. The test microorganisms were identified according to pathogenic, morphological and ecological characteristics, and the identification of Colletotrichum isolates was confirmed by polimerase chain reaction (PCR). Antifungal effect was tested using wells method and the obtained data were processed by factorial ANOVA. Duncan's multiple range test was used to test significance of differences (p≤0.05) between mean values of measured radius of inhibition zones. Activity of S. cervisae, B. cereus and L. mesenteroides was not satisfactory. On the other hand, S. hygroscopicus expressed the strongest antagonism against all tested fungal isolates. The studied isolate of S. hygroscopicus showed significant antagonistic properties against storage pathogens of apple fruits identifying itself as promising biocontrol agent for commercial use. © 2014 University of Bucharest.