Measurement of plant growth and health for optimal crop yield in LED horticulture (MePGhOL)

Growing urban populations and a shrinking land base means that the global level of food production will need to increase over the next 30 - 40 years and this will need to occur in the face of an unpredictable climate and lowered resource availability. Precision agriculture will play an important role in alleviating these problems and here we propose the novel use of plant sensors combined with efficient Light Emitting Diode (LED) arrays to increase the efficiency of crop growth in horticulture. We also propose the use of cutting edge genetics to assist with breeding tomato plants for high efficiency under LEDs. LEDs are set to replace existing horticultural lighting sources (such as sodium lamps) due to their low cost, long lifespan and high energy efficiency. We sit at a point where the uptake is yet to occur on a large scale so the market is potentially large and we expect new agri- markets to open as a result of the low cost and low infrastructure requirements of LEDs. We propose the novel use of plant sensors in combination with LED lamps to improve the energy efficiency of LEDs further. We will use spectral reflectance and chlorophyll fluorescence to assess plant area, photosynthetic functioning and 'health'. Data from these sensors will be supplied to a control unit that will modulate the output of the LEDs according to the requirements of the plant (leaf green area, photosynthetic capacity etc). It will also allow the grower to 'speed up' or 'slow down' the rate of growth to alter time to market and provide some novel possibillities for adjusting the morphology of the crop since the individual wavelengths will be tuneable. These adjustments will permit the optmisation of LED output, reducing energy costs.