A Dutch company has developed an ultraviolet crop protection system to fight molds, fungus, bacteria and viruses on crops without the use of chemicals.

The system "applies" a small dose of ultraviolet light that's deadly to the pests, but harmless to the plants themselves. It has been tested in greenhouses, vineyards, orchards and even on field crops like potatoes.

The company, Clean Light, worked with the Wageningen University in the Netherlands to develop the technology. The idea is to pass a series of ultraviolet light bulbs over the plants. Different size units are used depending on the crop. An on-board generator provides the electricity.

The method is based on the principle that both fungi and green plants are sensitive to ultraviolet light, but that there's a big difference in the lethal dose it takes to kill them. Fungi can be killed by a very low dose, while green plants tolerate much higher doses of ultraviolet light without showing sings of stress.

Clean Light says the idea stands to reason, given the fact that green plants survive and mostly thrive in full sunlight, while most fungi species only survive in surroundings that are sheltered from direct sunlight.

The new method leaves no residue on the crop, can be used under windy conditions, and avoids spray drift.

The company is interested in licensing the technology to other manufacturers.