In vitro screening of <i>Trichoderma harzianum</i> as bioremediator of mancozeb fungicide

Abstract The fungicide mancozeb is widely used to maintain and enhance crop yields. However, improper and continuous application can negatively impact both biotic and abiotic environmental quality. Bioremediation offers a promising solution to mitigate mancozeb residues, yet the use of Trichoderma spp. for this purpose remains underexplored. This study aimed to: (a) identify Trichoderma spp. from paddy fields with frequent mancozeb application, (b) evaluate the growth of Trichoderma spp. on PDA media containing mancozeb, and (c) assess their in vitro capacity to degrade mancozeb. The research was conducted at the Plant Disease Laboratory, Faculty of Agriculture, Universitas Nusa Cendana, from May to November 2023. Soil samples were collected from pesticide-treated paddy fields, and Trichoderma spp. were isolated using the serial dilution method. The isolates were cultured on PDA media containing mancozeb at concentrations of 0 (control), 2.4 mg/L, 3.0 mg/L, 3.6 mg/L, 4.8 mg/L, and 6.0 mg/L. Mancozeb degradation was evaluated using a modified dual-culture method with Alternaria padwickii as an indicator fungus. The findings revealed that: (a) Trichoderma harzianum was identified from pesticide-treated paddy fields, (b) it exhibited growth on PDA media containing mancozeb, and (c) it demonstrated potential as a bioremediation agent for mancozeb fungicide residues. These results highlight the potential of Trichoderma harzianum in mitigating environmental contamination caused by mancozeb.