In vitro antifungal screening of cacao pod husk and coffee husk extracts against phytopathogenic Neopestalotiopsis hispanica and Fusarium oxysporum

Abstract

Agricultural wastes raise concerns about their harmful environmental impacts, particularly when they accumulate and are not effectively managed. In this study, the potential of using coffee husk (CH), and cacao pod husk (CPH), two typical agricultural waste products were investigated, as safe alternatives to conventional fungicides against Neopestalotiopsis hispanica and Fusarium oxysporum. The effectiveness of these agricultural wastes' ethanolic extracts in inhibiting fungal growth was examined in vitro. Phytochemical compound screening revealed the presence of anthraquinones, flavonoids, tannins, saponins, and terpenoids in both extracts. The CPH and CH extracts showed a high rate of fungal growth inhibition against N. hispanica, which reduced mycelial growth by up to 66.62% and 59.02%, respectively. However, F. oxysporum only showed a reduction in mycelial growth up to 24.45% when exposed to CH extract, whereas CPH only caused a reduction of 6.30%. Despite the low inhibition rate, the colony morphology of F. oxysporum changed noticeably, especially as extract concentrations increased. These findings contribute to our knowledge of the potential antifungal properties of agricultural waste extracts, which may be used to control fungal diseases in a variety of crops.