Negative impact of some fungicide applications on Trichoderma harzianum as biocontrol agent of shallot moler disease

Abstract

Chemical control is still a mainstay for some farmers in shallot center areas such as in Brebes, Central Java. Applications of fungicides that are carried out in these areas are very intensive and are carried out periodically every 3-5 days. The application of fungicides that are too intensive can certainly have a negative impact on functional microbes including biological disease control agents. The purpose of this study was to evaluate the negative impact of the application of several brands of fungicides on the efficacy of T. harzianum as a biological control agent for red onion mole. Experiments were carried out in the field and in the laboratory. The results of the field experiment showed that the combined application of T. harzianum and fungicide did not increase the efficacy of a single application. While the results of laboratory tests with application doses in the field can inhibit the growth of colonies and germination of T. harzianum. Brand-B with active ingredients Carbendazim 12% and Mancozeb 63% can inhibit colony growth and germination 100%.