Does FreezePruf Topical Spray Increase Plant Resistance to Freezing Stress?

Abstract

One method of plant freeze protection involves the application of compounds that promote freeze avoidance or tolerance. FreezePruf, a commercially available product recently marketed to improve both freeze avoidance and tolerance, contains polyethylene glycol, potassium silicate, glycerol, silicone polyether surfactant, and a bicyclic oxazolidine antidessicant. The goal of the present study was to evaluate the protection level provided by FreezePruf using laboratory-based methods involving plants and plant parts from species capable and incapable of lowtemperature acclimation. FreezePruf did not lower the freezing temperature of pepper (Capsicum annuum) seedlings, celosia (Celosia argentea) seedlings, detached tomato (Solanum lycopersicum) leaves, or postharvest tomato fruit. Spray application of the putative cryoprotectant did not increase the freeze tolerance of bermudagrass (Cynodon dactylon) crowns or stolons. It is possible that a greater level of protection could be achieved with other species or different experimental protocols.

Frost Damage Mitigation in Flowers and Fruitlets of Peach and Almond from the Application of a Multi-Attribute Approach Biostimulant

“…α-Tocopherol and phospholipids improve the stability and integrity of the cell membrane, which improves freezing tolerance [ 43 , 44 ]. Glycols (polyols) and glycerol act as solutes or osmolytes that diminish the freezing point, both inside and outside plant cells [ 45 , 46 , 47 ]. The results against freezing damage in flowers and fruitlets could be improved by combining these components [ 7 ].…”

Chemical products for crop protection against freezing stress: A review

“…Chemical protection for crops or trees includes the use of different products that can be classified as conventional agrochemicals (e.g. nutrients or fertilizers, such as nitrogen (Scagel et al., 2010; Toca et al., 2018), potassium (Centinari et al., 2016; Ma et al., 2019), and calcium (Marosz & Nogowska, 2018; Vega et al., 1996)), biostimulants or growth regulators (Dwyer et al., 1995; Tsipouridis et al., 2006; Yang et al., 2019), pesticides (Robinson et al., 2015; Tsipouridis et al., 2006), and products whose main objective is to protect the crop or plant against freezing (Anderson, 2012; Francko et al., 2008, 2011; Hernández et al., 2016; Starkutė et al., 2017).…”

“…FreezePruf ® or Ecological ® FreezePruf ® (Patent WO2008/157555 A1; Francko et al., 2008) contains five ingredients: polyethylene glycol (PEG), potassium silicate, glycerol, a surfactant (silicone polyether), and an antidesiccant or anti‐transpirant (bicyclic oxazolidine). PEG and glycerol act as solutes or osmolytes that diminish the freezing point, both inside and outside of plant cells (Anderson, 2012; Francko et al., 2011). Moreover, the other ingredients in the FreezePruf ® formulation protect the plant by reducing water loss because they work as anti‐transpirants (Anderson, 2012; Francko et al., 2011).…”

“…PEG and glycerol act as solutes or osmolytes that diminish the freezing point, both inside and outside of plant cells (Anderson, 2012; Francko et al., 2011). Moreover, the other ingredients in the FreezePruf ® formulation protect the plant by reducing water loss because they work as anti‐transpirants (Anderson, 2012; Francko et al., 2011). However, contradictory results have been obtained for this product on crops and, therefore, more information on its effectiveness needs to be obtained.…”