There are a few cited reports explaining the furfural mode of action against soil microflora.
Flor (1926) first studied the fungicidal properties of furfural, reporting control of R. solani in potato.
In this regard, the end-use product containing 90% furfural in a liquid formulation is registered as commercial products, e.g. Crop guard, Multigaurd protect and Protect etc.
Pamphlet sheet of Protect (2005–2006) has demonstrated efficacy in the control of plant parasitic nematodes and fungal pathogens, i.e. Pythium, Fusarium, Phytophthora and Rhizoctonia.
Protect is a contact soil treatment that kills fungi by reacting with the cellular wall and disrupting cellular functions.
Also, it is obvious from Multigaurd fact sheet that it controls root infesting plant parasitic nematodes and fungal plant pathogens such as Pythium, Phytophthora, Fusarium and Rhizoctonia.
Moreover, drip irrigation treatments reduced populations of Pythium ultimum and F. oxysporum and increased stem height compared with the non-treated controls .