Plasma leads to faster plant growth and higher yields. Physicists, chemists, and biologists have been collaborating to understand the mechanisms driving this phenomenon. They want to fine-tune the application of plasma to plants so they can use it in agriculture.
Biochemist Alexander Volkov, a professor at Oakwood University in Huntsville, who has been studying the intersection of plasma and plants since the advent of the field, said:
Apply a plasma for too short a time, and we don’t get a positive effect. If it’s treated too long, it can modify or cause damage to the DNA.
He’s been comparing modes of plasma delivery. The experiments consist of treating seeds by exposing them to a plasma ball. The glass sphere generates filaments of glowing gas and high-frequency electromagnetic fields and photons. The energy improved the seed surface’s wetting properties and effectively corrugated it, consequently speeding up germination.
Plasma sheets also accelerated water uptake, a phenomenon known as imbibition, and consequently germination by changing the seeds’ surface properties.
Volkov explained:
Water can penetrate easily through spores and accelerate germination.
Plasma doesn’t affect all seed types equally. A different team of researchers from the Kingdom of Saudi Arabia’s Jazan University experimented with acacia, grape, sorghum, and heat seeds. The plasma treatment “etched” the surface of all seeds, but the effect as most pronounced in grape seeds, followed by acacia, then wheat, and sorghum. Regardless, all species experienced boosted imbibition and faster germination.
Engineer Katherina Stapelmann, from North Carolina State University, said:
The study suggests ways plasma could increase yields in countries that do not have harsh winters. Grape plants need a low temperature to break their dormancy and go back into their spring cycles. Direct treatment with plasma may serve that function and enable grape plants to grow.
I hypothesize that plasma will be most useful in improving unusual or high-value crops, rather than crops like corn that have already been optimized through genetic engineering. For specialty crops and others that are difficult to grow, this can improve the seeds’ growth and yield.
Meanwhile, scientists at Japan’s Nagoya University tried the plasma treatment directly on rice plants instead of the seeds. The results were promising. And another team from Kyushu University experimenting with radish seeds found that the seed’s color and age could influence the outcome of the plasma treatment.
