Plasma irradiation improves vegetable harvest

Scientists from Japan have successfully used ‘non-thermal air plasma irradiation’ to improve the harvest of a crop of salad leaves.

The ability to enhance the growth of crops and maximise their yields could transform food supplies for the future. Exposing seeds to ionising radiation allows scientists to control the growth and development of plants from the early stages through to harvest.

Plasma irradiation is a technique that does not damage the plants but has been shown to increase seed germination rates and overall plant length. Researchers from Kyushu University have demonstrated that the use of non-thermal air plasma irradiation can dramatically improve the harvest of the salad crop Arabidopsis thaliana.

The team built a scalable device to generate the non-thermal plasma and placed 20 A. thaliana seeds under the device before subjecting them to a three-minute dose of plasma radiation. The seeds were then planted and their growth and proliferation was monitored and compared with a control group.

The researchers found that the germination rate for the plasma seeds was almost a full day faster than the controls. The plasma plants reached maturity at 17.5 days, compared with 22 days for the control group. The seeds produced by the plasma group were larger, with a 39% overall increase in seed number.

The results represent an 11% shorter harvest period and a 56% increase in total seed weight; a significant improvement in crop yield.

The research is featured in Applied Physics Express.