Agriculture is the single largest contributor to Ireland’s overall greenhouse gas emissions, accounting for over 30% of the total. Not only that, but agriculture already accounts for over 66% of land use nationally. With the world’s population estimated to increase by over a third by 2050, we are very quickly looking at 2 billion extra mouths to feed. Professor Marcel Jansen and Doctor Alan Morrison from UCC are tackling this problem by exploring ways to make the current food production processes more sustainable as well as increasing the nutritional value of the crops.
Ultraviolet light (UV) from the sun is a key factor in plant development, the amount of sun plants receive can impact their nutritional value, architecture and ability to resist pests. Unfortunately, here in Ireland we only get between 1100 and 1600 hours of sunshine each year, compared to southern Spain where they can get upwards of 2200. Professor Jansen and his team at UCC’s Environmental Research Institute are aiming to develop state-of-the-art LED technology that will enable scientists to manipulate UV light to advance our understanding of how plants respond to different UV-wavelengths.
UV light is broken down into different categories depending on its wavelength. The most commonly known types of UV light are, UV-A and UV-B, which have been studied extensively for their effect on living things, particularly UV-B, as ozone depletion means more UV-B rays reach the surface of the earth. As with humans, when thinking of UV exposure in plants, a good rule to follow is that a little UV is good for you, promoting vitamin D production in the skin, but a lot can have detrimental effects, such as sunburn. Previous studies by Prof Jansen have shown that when plants are exposed to low dose UV-B light it alters the nutritional value, pest tolerance, and hardiness of plants and plant tissues.
This is good news for farmers and consumers, but growing plants under UV light is expensive and the lightbulbs often contain hazardous materials like mercury. What Prof Jansen and Dr Morrison propose to do is develop energy efficient LED lights in the UV spectrum, and combine these with visible light LEDS, so that a full sunlight spectrum is created. LED lights are much cheaper to run as they require only a fraction of the energy of traditional bulbs. The UV LED lights will also be specific to either UV-A or UV-B light so that the researchers can determine how much of each light form is needed to get the best out of the plants. Once perfected the only way is up for indoor horticulture, we could see greenhouses as tall as an office block.