THE Israeli company with links to Australian horticulture irrigation trials has completed its world-first pilot in a commercial operation combining its innovative irrigation technologies to highlight robust lettuce growth and a 20 per cent shorter growth cycle.
Roots Sustainable Agricultural Technologies conducted its pilot of Root Zone Temperature Optimisation (RZTO) temperature control and Nutrient Film Technique (NFT) technologies to cool the nutrient temperature of hydroponic lettuce in Bnei Atarot in Central Israel.
The two technologies combined to ensure the water delivered dissolved nutrients to hydroponic bare plant roots remained within favourable growing ranges more than 11 degrees lower than the ambient air temperatures in the greenhouse of nearly 40 degrees.
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The company says this increased production quality and shortened the growing cycle by about 20pc compared to traditional plantings where no nutrient temperature control is used.
The successful RZTO and NFT operation, which Roots unveiled at the recent AgriTech Israel conference in early May 2018, shows the ability of the technology to allow farmers to stabilise nutrient temperatures to increase yields and profits dramatically through more efficient crop management – even in extreme summer weather conditions.
Roots Sustainable Agricultural Technologies continues to use Australia as a base for trialling its groundbreaking irrigation system and gathered attention at the end of last year when it detailed its crop irrigation method which uses moisture drawn from the atmosphere overnight.
It has patented the method as "Irrigation by Condensation" method.
Roots chief executive officer, Dr Sharon Devir said it was a breakthrough in greenhouse crop control.
“No other commercial company in the world, as far as we know, is offering RZTO and NFT cooling systems for hydroponics or other substrates such as grow bags or soil,” Dr Devir said.
“Until now, the only option farmers had to reduce heat load in greenhouses was to use large evaporative cooling systems with several fans.
“However, they are expensive to buy and operate, use a lot of energy, and increase humidity levels within the greenhouse which increase disease levels on plants.
“RZTO cooling systems have none of those issues and focus on retaining core temperatures at the root zone – not in the ambient air.
“Cooling the NFT nutrient solution was made by ground source heat exchange only, using a circulating pump which consumed only 1.5kw/h of energy.
“Since installation at this site there were several days close to 40 degrees centigrade accompanied by very strong wind storms, one of which caused shade nets above most greenhouses in the region to blow away.
“While many nearby greenhouse crops did not survive these extreme weather conditions, the Roots’ cooled crop survived four hours of strong wind and severe heat without any shade net.
“The RZTO and NFT cooling system was effective in stabilising the crop temperatures despite these extreme external weather conditions where the fragile crops were completely open to the heatwave and windstorm conditions.”
“In NFT greenhouses without the combined RZTO and NFT technology, the nutrient temperature of crops closely followed the air temperature in the greenhouses.”