Survival and Transmission of Potato Virus Y, Pepino Mosaic Virus, and Potato Spindle Tuber Viroid in Water

Abstract

Hydroponic systems and intensive irrigation are used widely in horticulture and thus have the potential for rapid spread of water-transmissible plant pathogens. Numerous plant viruses have been reported to occur in aqueous environments, although information on their survival and transmission is minimal, due mainly to the lack of effective detection methods and to the complexity of the required transmission experiments. We have assessed the role of water as a source of plant infection using three mechanically transmissible plant pathogens that constitute a serious threat to tomato and potato production: pepino mosaic virus (PepMV), potato virus Y (PVY), and potato spindle tuber viroid (PSTVd). PepMV remains infectious in water at 20 ؎ 4°C for up to 3 weeks, PVY (NTN strain) for up to 1 week, and PSTVd for up to 7 weeks. Experiments using a hydroponic system show that PepMV (Ch2 genotype) and PVY (NTN strain) can be released from plant roots into the nutrient solution and can infect healthy plants through their roots, ultimately spreading to the green parts, where they can be detected after a few months. In addition, tubers developed on plants grown in substrate watered with PSTVd-infested water were confirmed to be the source of viroid infection. Our data indicate that although well-known pathways of virus spread are more rapid than water-mediated infection, like insect or mechanical transmission through leaves, water is a route that provides a significant bridge for rapid virus/ viroid spread. Consequently, water should be taken into account in future epidemiology and risk assessment studies.

Potato spindle tuber viroid: Stability on Common Surfaces and Inactivation With Disinfectants

“…In contrast, transmission following tomato fruit handling was considered unlikely unless the fruit has been squashed to release its sap (46). However, recent findings by Mehle et al (24) suggested that PSTVd transmission via roots through water-mediated movement is of concern in hydroponic and intensive irrigation systems, with PSTVd infectivity surviving in water for up to 7 weeks. However, recent findings by Mehle et al (24) suggested that PSTVd transmission via roots through water-mediated movement is of concern in hydroponic and intensive irrigation systems, with PSTVd infectivity surviving in water for up to 7 weeks.…”

Filling the gaps in diagnostics of Pepino mosaic virus and Potato spindle tuber viroid in water and tomato seeds and leaves

“…() (Table ) were used for PSTVd and PepMV detection, respectively, as described by Mehle et al . (). For detection of CLVd, the one‐step RT‐qPCR of Monger et al .…”

“…Just one infected plant grown from a single infected tomato seed has the potential to rapidly spread the infection mechanically to neighbouring plants, resulting in a larger outbreak. Recently, it has also been shown that irrigation water can be a path for PepMV and PSTVd transmission between plants (Mehle et al, 2014). Therefore, it is essential to monitor for these pathogens through all of the critical points in tomato production and pathogen transmission pathways.…”

“…() was used and performed as described by Mehle et al . (). A cytochrome oxidase ( COX ) gene‐specific real‐time RT‐PCR assay was used as the endogenous control (Weller et al ., ).…”

Host range and symptomatology of Pepino mosaic virus strains occurring in Europe

“…There is evidence that bumble bees (Shipp et al 2008), the soil-borne fungus Olpidium virulentus (AlfaroFernández et al 2009) and whiteflies (Noël et al 2014) can function as vectors for PepMV. Seed transmission is likely to play a role in long distance spread (Córdoba-Sellés et al 2007;Hanssen et al 2010), and water was confirmed to be the source of PepMV infection (Schwarz et al 2010;Mehle et al 2014).…”