"Priming seeds with plasma provides possible defense against damping off"

Vigorous seedling growth may provide an additional defense against ‘damping off,’ a global cause of spinach loss. Trials by Zayndu suggest that priming spinach seed with its plasma treatment accelerates germination by 1.5 days, increasing resilience in the seedlings. The company is exhibiting at the Brassica and Leafy Salad Conference on 25th October 2022. 

Damping off is caused by Pythium spp. and Rhizoctonia solani, soil-infesting microbes that can build up rapidly and attack young germinating seedlings when soil is moist. There are a number of conventional and biological seed treatments for Pythium, and the overall aim is to promote rapid and vigorous seedling growth. 

Spinach is one of over 23 different crop plants that Zayndu has disinfected with its Aurora system. Aurora generates a plasma in its drum when an electric current moves through the air, splitting oxygen and nitrogen molecules and creating a powerful disinfectant for the seeds without the need for chemicals or water. 

Seed pathologist Dr. Alberto Campanaro leads the R&D facility at Zayndu. He says that its trials have shown treatment with the Aurora Z10 model not only reduces the fungal load from the spinach seeds to about 4% but also primes the seed, stimulating plant growth. 

He comments: “Germination was 15% higher in the spinach seed treated in the Aurora Z10 and the window shorter, with 70% of the seeds germinating within six days, compared to 60% of the untreated batch. The seedlings had increased vigor, which is key if they are to outgrow damping off.” 

Damping off causes major crop losses, and the keynote speaker at the Brassica and Leafy Salad Conference is Dr. Catherine Eyre, Plant Pathology Consultant at ADAS Horticulture, who will be presenting findings of a grower-led spinach damping off trial, using current treatments. 

Currently, the Zayndu technology is designed to treat smaller batches of seed at regular intervals, and so is ideal for Controlled Environments and vertical farms producing baby leaves. However, the company is working to scale up its system and is looking forward to talking to seed breeders, and vegetable growers at the conference about their requirements and the potential for inclusion in Integrated Pest Management approaches. 

“Accelerated germination, when combined with a biological treatment, may confer additional protection to the young crop,” suggests Dr. Campanaro. “I am very interested to hear the results of the AHDB trial and perhaps to explore the potential for treating seed used in future trials.” 

The Zayndu plasma treatment primes the seed chemically and physically. The reactive oxygen and nitrogen species (RONS) created induce hormonal changes in the seed, which can influence plant growth from seed to crops*. Studies report increased root length and enhanced growth of seedlings, depending on the dose given. Physical changes to the surface of the seed make its coat more permeable to water, triggering germination. 

Zayndu will be at the Brassica and Leafy Salad Conference on 25th October 2022 at the East of England Showground, Peterborough.