PlasSeed: Gas Plasma for Seed Disinfection

Lead Research Organisation: Royal Holloway, University of London
Department Name: Biological Sciences

Abstract

In order to keep pace with the world's expanding population, global crop yields are required to double by 2050 and this requirement is made even more challenging by the rising global temperatures and emerging erratic weather patterns caused by climate change. To meet this challenge with minimal environmental impact, it is imperative that the productivity of agricultural land is increased through strategic and technological advances.

Seed-borne pathogens attack developing seedlings, compromising germination and plant establishment and ultimately reducing crop yield. As a result, seeds need to be disinfected and this is typically achieved by washing seeds with or without chemical additives, coating the seeds with fungicide, or soaking germinating seedlings in fungicide drenches. Such approaches have limited applicability as they can affect the germination of the seed and they are not effective in treating all diseases. In addition, due to stricter regulatory controls on the use of chemical agents, seed companies are in need of alternative means of disinfecting seeds without negatively affecting their viability.

PlasSeed proposes the use of gas plasma technology as a novel and potentially revolutionary means of disinfecting seeds. Gas plasma has been shown to have a broad range of antimicrobial properties and the technology offers a chemical-free, dry, low-energy alternative to existing seed disinfection techniques.

Technical Summary

Low temperature plasmas are ionised gases containing cocktails of electrons, ions, radicals, excited species and photons under conditions that are far from thermodynamic equilibrium. As a result, plasmas can generate reactive environments at low temperature to initiate and catalyse chemical processes. Semiconductor fabrication, large area displays and energy-efficient lighting are examples of technologies that have been enabled by advances in plasma physics and engineering.

In recent years, advancements in the generation of nonthermal plasmas at atmospheric pressure has revolutionised plasma technology, opening up a host of new applications in biology and medicine. In particular, the capacity for microbial decontamination of a wide range of biotic materials (e.g. disinfection of wounds) has been amply demonstrated (Lu, X et al. 2016 Phys. Rep. 630, 1).

PlasSeed extends the use of this technology to the disinfection of seeds. This is a timely development that will address the pressing need for a scalable, effective, dry and chemical-free technology for seed disinfection. In collaboration with national and international industry partners, PlasSeed will develop plasma seed reactors and assess their efficacy in disinfecting a range of naturally contaminated seeds.

PlasSeed will perform experiments on batches of seed of large enough quantity (>30000 seeds) to warrant proper statistical results and naturally contaminated seeds will be used to overcome the shortcomings of artificial inoculation. The project will assess the efficacy of the treatment against epiphytic (superficial) and endophytic (deep-seated) pathogens, studying physical and biochemical changes triggered in the seeds and any long term effect on the growing plantlets.

Planned Impact

The anticipated beneficiaries of this work include:

- Society: PlasSeed addresses an urgent problem faced by seed companies and contributes towards addressing the increasing pressure on global agriculture, food security and the environment. These are areas of global concern in which the government and UK funding bodies are strategically investing in. Successful completion of PlasSeed will contribute towards a sustainable future by providing an environmentally-friendly disinfection process for crop seeds that will have benefits on the health and quality of life of future generations.

- PlasSeed academic partners: Given the incipient state of the field of plasma agriculture, the proposed project pushes the current frontiers of gas plasma technology for the disinfection of seeds. Any breakthrough will create opportunities to lead in this rapidly growing field and will be welcome by the community. The academic partners will also establish a long-lasting collaboration in which complementary expertise held by each group will be combined to address more efficiently larger scientific and technological challenges in the future.

- PlasSeed industrial partners: With increasingly stringent regulations around the use of fungicides and concerns over xenobiotic residues in food production, seed companies are in urgent need of an innovative chemical-free disinfection process that can achieve its objectives without damaging the germination potential of seeds. PlasSeed promises one such solution and moreover, early access to and adoption of the technology by Elsoms Seeds and Bejo Zaden would give them an advantage over their competitors, positioning a UK company at the global forefront of seed disinfection.

- PlasSeed partners: All parties are committed to secure and exploit any intellectual property (IP) arising throughout the duration of the project. This could potentially provide another revenue stream for both the industrial partners and the academic institutions.

Publications

10 25 50
 
Description Gas plasma is considered to be the fourth state of matter. Current applications for gas plasma involve cleaning and treating manufactured surfaces for a variety of industrial and medical processes. Gas plasmas are associated with the formation of a myriad of free radicals which can react with macromolecules in their proximity. With non-thermal (cold) atmospheric-pressure gas plasma (NTAGP) technologies, this is achieved without heat generation and at atmospheric pressure allowing for the treatment of sensitive biological tissues. This property has been proven useful in developing new medical applications for dentistry and oncology, and additionally provide an excellent sterilization tool for food and food packaging. New trends of sustainable agricultural applications of NTAGP, including plant, seed, and food treatments, are currently emerging as a rapidly developing innovative field called "plasma agriculture". This includes the inactivation of seed-borne microorganisms, as well as the stimulation of seed germination and seedling growth by NTAGP treatment.
Exploitation Route Interaction with several seed companies are ongoing.
Sectors Agriculture, Food and Drink,Environment

URL https://gtr.ukri.org/projects?ref=BB%2FS016112%2F1
 
Description Currently ongoing, interactions with several seed companies.
First Year Of Impact 2019
Sector Agriculture, Food and Drink,Electronics,Environment
Impact Types Societal,Economic

 
Description BBSRC CTP iCASE PhD studentship with Croda/Incotec - PhD student Bernice Mitchener - Crop seed quality refinement with beneficial microbes
Amount £123,879 (GBP)
Funding ID BB/T508913/1 
Organisation Biotechnology and Biological Sciences Research Council (BBSRC) 
Sector Public
Country United Kingdom
Start 01/2020 
End 12/2023
 
Description Gas plasma as a novel seed technology 
Organisation Loughborough University
Department Wolfson School of Mechanical and Manufacturing Engineering
Country United Kingdom 
Sector Academic/University 
PI Contribution Interdisciplinary collaboration between Dr Felipe Iza (electrical engineering, gas plasma engineer) from Loughborough University. We at Royal Holloway are providing molecular seed physiology (my expertise and most of my groups expertise) as well as seed biomaterial engineering and seed technology (Dr Tina Steinbrecher, biomaterial engineer).
Collaborator Contribution Interdisciplinary collaboration between Dr Felipe Iza (electrical engineering, gas plasma engineer) from Loughborough University. They are providing the engineering part of gas plasma devices for several collaboration activities.
Impact Multi-disciplinary collaboration/partnership including molecular seed biology, seed biomechanics, gas plasma and electrical engineering.
Start Year 2016
 
Description Vegetable Seed Health Research with Bejo 
Organisation Bejo Zaden
Country Netherlands 
Sector Private 
PI Contribution Vegetable seed health and quality research into gas plasma as novel technology for seed lot disinfection
Collaborator Contribution Provision of vegetable crop seed lots with defined contamination with seed-borne pathogens
Impact Too early to say
Start Year 2019