Roots Sustainable Agricultural Technologies Limited (ASX: ROO, Roots or Company) has increased total plant yield of tomatoes by 19 percent using its patented Root Zone Temperature Optimisation (RZTO) heating technology, compared to unheated control crops.
The commercial demonstration was conducted in greenhouses in Almeria, Spain during the Spanish winter from December 2018 to March 2019. A warm-climate crop, tomatoes are sensitive to frost and cold stress throughout the growing cycle. Roots’ RZTO heating technology was used to maintain the crop root temperature at a relatively stable range around 21 degrees, despite ambient air temperatures in the greenhouse frequently dropping to 10 degrees. The roots zone temperatures of control plantings fluctuated between 10 and 22 degrees over the same period.
According to the literature, stabilising the root temperature of tomato plants throughout winter increases the absorption of water and fertilizers, which in turn improves the flowering and quality of the fruit. Globally, 177 million tonnes of tomatoes were grown in 2016 – a rise of nearly 30 per cent in a decade. This production covers approximately 5 million hectares with an average yield of 3.7 kg of tomatoes harvested per square metre . However, in Spain the yield is 8.62 kg per square metre – more than double the global average.
In Spain, Almeria and Murcia are the main regions for fresh tomato production and export. Almeria in particular is characterised by small-scale family farms where cultivation is mostly in ‘enarenado’ – a 30cm layer of soil on top of the natural soil, followed by a 2-3cm layer of organic compost and a 10cm top layer of sand.
Roots CEO, Dr Sharon Devir said, “We are very excited by the fact that our RZTO technology caused a significant yield increase on Spanish tomato crops – already among the most efficiently farmed in the world. While Spain is a leading producer of fresh tomatoes within Europe, cold stress has a significant impact on the growth and development of tomatoes during cooler months. In addition to lost revenue from damaged plants, cold stress can injure both the above and below ground plant tissues, reducing crop quality and delaying the maturation of plants. Despite being grown in greenhouses with added soil protections,
traditional growing and heating methods in Spain haven’t been able to mitigate significant overnight drops in
temperature.
By using RZTO to heat the roots of tomato plants during autumn and winter, the farmer was able to mitigate
the impact of cold stress and injury. Root zone heating ensures the roots’ crop remains at optimal
temperatures throughout the growing season, resulting in healthier crops and increased produce during the
off-season.