What Is Crops Cold Stress
Cold stress is the main abiotic stress affecting plant yield and quality worldwide. The cold resistance ability of crops namely is the tolerance of crops to low temperatures. It has a positive significance for agricultural production that finds out the reasons for the harm of low temperature to crops and the law of cold resistance of crops, so that improving the cold resistance of crops.
It can be divided into freezing damage and cold damage according to the degree of low temperature and the damage situation.
Freeze damage: The phenomenon that the temperature causes freezing inside some crops, causing injury or even death when the temperature drops below 0℃, is called freezing injury.
When the temperature drops continuously or plummets to a very low level, it will cause not only the freeze of plants' intercellular space, but also the water in the cells will freeze, and the water in the protoplasm will form small ice crystals, which will directly destroy the structure of protoplasm and do the most serious harm to crops.
Cold damage: It means the harm of low temperature above 0 ℃. In a word, the low temperature above freezing point causes the physiological obstacles of thermophilic crops, causing crops to be injured or even killed.
It is complex that the causes of cold damage to crops. It will destroy the coordination of protoplasmic structure and metabolism. When the crops are damaged by cold, the respiration often increases, the energy in the body is reallocated, the heat increases, and the high-energy compounds decrease, resulting in a shortage of internal energy and metabolic disorders in the crop body.
How to Improve Crops Cold Resistance Ability
The improvement of crops cold resistance goes through two stages:
First, try to make the crops have vigorous photosynthesis before winter to accumulate more "protective substances" (sugars and amino acids, etc.). Increase the content of unsaturated fatty acids in membrane lipids. This has important significance in preventing the phase transition of the biofilm and stabilizing the membrane structure.
The second is to control field irrigation under stable low-temperature conditions in late autumn so that plants can carry out the normal dehydration process of cell space and normal changes in the colloidal state of protoplasts, reduce the free water content in plant tissues, and thus reduce the possibility of tissue freezing.
The ability of plant cold resistance was related to soluble sugars, membrane phospholipids, proline, especially abscisic acid, and membrane fatty acid unsaturation.
Maintaining the stability of the function and structure of the biofilm system is the basis for maintaining and improving the cold resistance of plants.
Agronomic cultivation methods: Greenhouse cultivation and film mulching are used to increase the temperature and improve the growing environment of crops in winter. Hybrid breeding or genetic engineering can also be used to cultivate varieties with excellent cold resistance to reduce the adverse effects of low temperatures. However, improving agronomic practices is time-consuming and laborious.
The cold resistance resources of cross breeding are insufficient, the selection cycle is long, and the genetic engineering technology is difficult.
One relatively simple way is improving the cold resistance of crops by using exogenous substances which mainly include Plant growth regulators, such as abscisic acid, brassinolide, salicylic acid, etc.; Osmoregulation substances, such as soluble sugars, betaine, etc; Inorganic salt ions, such as Ca +, K +, and Biostimulants, such as seaweed extracts, amino acids.
Overall, using Dora kelp fertilizer or seaweed fertilizer can help crops build cold stress resistance, to overcome the climate changes. Contact us for more details.