Plants are continuously exposed to adverse environmental factors during their lifecycle. Cold stress is one of the most important abiotic stresses that can affect the growth and development of crops.
The impact of cold stress has increased in recent years due to the ongoing climate breakdown. Conditions have become more unpredictable, with longer and more severe cold or frost incidents, and areas that previously did not suffer from cold or frost periods now experience them. All these factors combine to impact on crop growth, and eventually grower yield and profitability.
How does cold and freezing impact plants?
Different plants show a variable degree of cold tolerance, and, within the same crop, individual plants will have different levels of tolerance due to differences in microclimate and localised nutritional status.
Cold or frost damage occurs when ice crystals begin to form between and within cells producing physiological, biochemical (such as decreases in protein formation), metabolic and molecular changes.
Ice forms first outside cells (extracellular water) because the area outside the cells has a lower solute concentration and freezes quicker (i.e. it is like pure water). Typically, only this extracellular water freezes during a “light” frost.
Water inside cells (intracellular water) takes longer to freeze as it has a high concentration of solutes (e.g. Potassium) and conceptually can be thought of as salty water. Since it requires lower temperatures and takes longer to freeze, this typically occurs during a “heavy” frost.
Both types of cold and freezing can cause cells to burst or other physiological effects although the freezing of the intracellular water is obviously more damaging to the plant. Reduced metabolic processes are common consequences of cold stress in plants and produce negative effects such as:
Growth inhibition/growth reduction.
Cell walls/membranes function poorly preventing the cells from maintaining ionic gradients.
Reduced absorption and translocation of water and nutrients.
Dehydration causing loss of turgor/cell strength resulting in plants that wilt, even when soil moisture is adequate.
Flower drop.
Bud death or necrosis.
Reduced reserves of sugar and energy; both as a result of the reduced sugar production and through their increased use by the plant during cold periods.
How can I protect my crops from frosts and cold damage?
The first Biostimulation 360º strategy consists of the application of abiotic stresspreventive Biostimulants. These products typically exhibit the Tradecorp “Primactive” effect. The application of preventive products should ideally be done 7-10 days before the cold stress starts, with the aim of preparing the crops to resist against the negative effects of the cold temperatures.
Tradecorp’s range of Phylgreen products, based on 100% pure Ascophyllum nodosum seaweed extract, provide osmolytes that help resist osmotic stress. Examples of the osmotic stresses consequences caused by freezing that Phylgreen can help plants resist are: cell expansion from freezing, incorrect ionic gradients and reduced water uptake.
Phylgreen also supplies plant energy sugars such as Mannitol, which is a known osmolyte, to help plants resist the eventual cold stress situation. When the osmotic compounds are accumulated outside and within cells, they help decrease the difference of osmotic gradient between liquid water and extracellular ice. This helps to reduce the dehydration and crystallization of the ice.
Separately, Mannitol also acts as a source of energy for plants so that they can continue to grow during cold periods. Of course, in heavy frosts with complete freezing some damage to crops will inevitably occur.
During and after stress biostimulants
Sometimes climate conditions change drastically and there is not enough time to apply a preventive treatment. In these situations, Tradecorp has other Biostimulation 360º curativeproducts for use during and after the cold stress events.
For example, Biostimulation 360º products based on L-α Free Amino Acids, such as Delfan Plus or Vegenergy, have a strong a curative action against abiotic stress. A well-balanced proportion of these L-α Free Amino Acids, and their high content (i.e. the Aminogram), provide an immediately plant useable source of energy ensuring plants have the energy needed to recover during or immediately after the abiotic stress period. These curative products enhance the formation of plant proteins that confer the ability to better tolerate cold and to recover more quickly from stress.
For more information on Tradecorp, Biostimulation 360 and management of cold and other abiotic stresses please contact your local Tradecorp office, representative or select country.
