Solid-phase micro-extraction (SPME) in the early detection of potentially active volatile compounds from organic wastes used for the management of soil-borne pathogens

Abstract

The complex molecular assemblages were analysed in the soil gas phase after applying pine forest wastes (PFW) or sugarbeet vinasses (SBV) for soil-borne crop pests management. For this purpose, solid-phase micro-extraction (SPME) and gas chromatography (GC) were used coupled with mass spectrometry (MS). The organic wastes were applied either to Calcic Entisol or Haplic Arenosol moistened at field capacity and soil was covered with polyethylene sheet for 28−30 days to retain the volatiles. The PFW-treated soil mainly released volatile terpene hydrocarbons (trans-caryophyllene, β-myrcene and p-cymene), with α-humulene and ethylbenzotriazole prevailing in the untreated soil. After SBV application mainly alkyl compounds and alkylbenzenes were released, whereas cyclohexanone, limonene, butanone, acetic acid, camphor and benzaldehyde occurred in the untreated soil. Compound assemblages also depended on the increasing water saturation in terms of soil depth, with sulphur compounds prevailing in deep horizons. Our results showed that SPME can be directly applied to soils to provide valuable information on volatile products from organic amendments.

Gases Released During Soil Biodisinfestation of Pepper Greenhouses Reduce Survival of Phytophthora capsici Oospores in Northern Spain

“…Several strategies based on the use of organic amendments for soilborne disease management have been studied to improve its efficacy and to elucidate the soil disease suppression action mechanisms that are directly or indirectly involved in their application (Bonanomi et al, 2010(Bonanomi et al, , 2018Gamliel and Stapleton, 2017;Rosskopf et al, 2020). One of these approaches combines soil solarization with organic amendments for an improved control of soilborne pests, named "biosolarization" (Katan, 2005;Ros et al, 2008) or "biodisinfestation" (de la Fuente et al, 2009). The term soil solarization refers to a soil disinfestation method which uses passive solar heating of moist soil mulched with transparent plastic sheeting for the control of pathogens, mainly through a direct thermal inactivation mechanism (Katan et al, 1976;Stapleton, 2000).…”