Reducing pest control costs with thermaculture
Les Collines began treatments shortly after bud break and treated every seven days, covering all of its 240 acres each week.
“We were very happy with the early season control of pests, especially thrips, mites and powdery mildew,” McKibben said. “In total, we decreased our pest control passes in half and might have done better had it not been for machine and tractor issues that prevented us from frequent enough treatments about mid-season.”
“In addition, you fill up the propane tank and you get eight hours of uninterrupted treatment with the AgroThermal machine,” McKibben said. “With sprays, you have to continually return to the shop, mix up the solution and fill the tank, so there’s lots of wasted time mixing and back and forth. It’s no surprise my employees really like the heat treatment machine, since it was faster and easier than dealing with sprays.”
McKibben expects to see further benefits, such as increased yields and better tasting wines.
“It is also nice to have a machine available that could help us save some late-season grapes in case we get rain in the fall.” said McKibben, who estimates, based on the pest control savings, that the Thermaculture machine would pay for itself in the first year, and that any increase in wine quality or yields will be added value.
Agrothermal is working with two wine genome scientists at the University of Bordeaux in France as they attempt to identify the genome pattern of thermal plant treatment. They are studying how the genome functions and its role in creating wine responding to climatic and other inputs. AgroThermal is working closely with the Bordeaux group on long-term studies that were underway with the 2015 crop year.
“After three years of trials, chemistry analyses and multiple blind taste tests in various countries, recent discussions at the Ecophysiology and Grape Functional Genomics Research Unit with wine genome scientists have led to a program that will further investigate the effects of thermal plant treatment on wine grape berry composition and the resulting wines,” said Marty Fischer, AgroThermal Systems founder and CEO. “For several years now we have seen treated blocks produce more complex, youthful wines with different aromas that have been generally preferred over wine made from grapes that were produced from the same blocks but without heat treatments. The answer may lie in ‘heat shock’ and the manner in which this leads to changes in vine physiology.”
Fischer has had discussions with the University of Gambetta’s Serge Delrot and Gregory Gambetta, who specialize in the wine grape genome’s functions and its role in creating wines responding to climatic and other inputs.
“What had occurred to us, was by heating the canopy instantaneously by some 12˚ F-20º F, our technique was achieving an input to the plant that it had never experienced before, and that this instant heat increase might be activating pathways never triggered by the normal rise and fall in ambient temperatures” Fischer said.
The Bordeaux group acknowledged this type of heat input would likely trigger differences in vine physiology.
“This level of instantaneous heating of the canopy and grape berry surfaces could create ‘heat shock’ leading to differences in aroma and other wine sensory characteristics,” said Delrot, director of the EGFV Joint Research Unit (University of Bordeaux, INRA and Bordeaux Sciences Agro). “It is an interesting new approach to evoking different wine characteristics and plant behaviors that requires exploration and further study.”
AgroThermal is working with the EGFV Research Unit to establish longer-term studies of how instant heating of the vine triggers changes in fruit and wine composition.
The initial work took place during the 2015 crop year.
“To my knowledge, no in-depth work has been done on the novel idea of instantaneous heat shock in grapes,” Delrot said. “It is a fascinating way to try to manipulate plant behavior and has implications not only for fruit production, but also for levels of production, blossom development and even the plant’s ability to react to disease and pest pressures,” Delrot said.
According to Fischer, AgroThermal Systems has seen these kinds of plant behaviors not only in grapes but in other produce items.
“We are focused on wine grapes in our research and marketing efforts after years of work that show this technique works,” he said. “In the beginning years of the technique, however, it produced some very interesting benefits for cherries, other orchard fruit, berries and even processed tomatoes.”