Since its launch in 2022, the PPS Air Monitoring project has entered an advanced phase. The goal: to understand the presence and spread of plant pathogens through the air. New findings from both lab and practical trials show that greenhouse air sampling is indeed proving valuable as a tool for early disease detection.

Catching air in the greenhouse
Within the project, different air-sampling devices are being tested, including the Rotorod and the Pollensniffer. Both systems have shown themselves to be effective in capturing spores of powdery mildew, grey mould (Botrytis), and Pseudomonas. The devices run 24 hours a day and can be deployed specifically during periods of elevated risk.

DNA analyses reveal what is present in the air
After collection, air samples are analyzed using DNA sequencing techniques. Researchers have chosen the MinION platform (Nanopore sequencing), which delivers longer DNA reads and therefore more precise identification.

The analyses show that the air in and around greenhouses contains a rich mix of microorganisms, plant material, and pollen. Alongside familiar pathogens, large amounts of "background DNA" from plants and bacteria are also detected. Interestingly, the DNA profiles inside greenhouses differ markedly from those found outside.

From lab to grower
In addition to trials in the demo greenhouse at Wageningen University & Research in Bleiswijk, air samples have also been collected at six commercial growers (cucumber, rose, and gerbera). In all cases, both powdery mildew and Botrytis were detected. With qPCR and LAMP technologies, the quantity of pathogen DNA present could be determined with high accuracy.

One of the project's most intriguing innovations is the ultrafast qPCR chip, developed by Imec together with Wageningen UR. This chip can detect minute amounts of pathogen DNA within just 10 minutes, opening up possibilities for rapid on-site monitoring.

Next step: linking with cultivation conditions
The coming phase of the project focuses on long-term monitoring in commercial greenhouses. Air data will be linked to metadata such as climate, disease pressure, and cultivation practices. The aim is to better understand which factors influence disease spread, and to explore whether air analysis can support growers in their crop protection strategies.

Collaboration and funding
PPS Air Monitoring is a public–private partnership within the Dutch TKI Horticulture & Starting Materials program. Two Wageningen UR business units are involved: BU Biointeractions & Plant Health and BU Greenhouse Horticulture.

The project brings together a wide consortium of partners. The main funders are the Dutch Ministry of Agriculture, Nature and Food Quality (LNV) and Glastuinbouw Nederland (project coordinator), within the Het Nieuwe Doen in Plantgezondheid innovation program of Kennis in je Kas (KijK). Other partners include the crop cooperatives for cucumber, gerbera, and rose, as well as Naktuinbouw, Royal Brinkman, Pessl Instruments, Bertin Instruments, 20/20 Seedlabs Inc., OnePlanet/Imec NL, and Leiden University of Applied Sciences.
 

Source: www.floraldaily.com