Plants use all possible internal reserves to survive in the external environment.
Thus, to protect against parasites in the cells of the plant at the slightest contact a process of necrotic action is formed, which leads to the death of the parasite. This theory appeared in 1940 thanks to the German professor K. Müller and his assistant K. Borger and is called phytoalexins (from Greek phyton – plant, alexo – attack reflection).
The concept of plant phytoalexins
Plant phytoalexins arise exclusively in living cells and represent some chemical composition, which is a product of necrosis of the host plant cells. The rate and strength of phytoalexin formation depends on its genotype.
Phytoalexins can be found in different plant families, but they are all close in structural type. They are found in nightshades, legumes, umbrellas, compound flowers, and marae, but are absent in cereals. They can be different in different plants and different types and compositions of phytoalexins and antibiotics can be formed in response to the parasite and infection.
Phytoalexins are absent in healthy plants; they are the final, final product of a plant infected with a parasite (the result of an attack on an alien product).
Significance of phytoalexins, mechanism of production
Phytoalexins play a critical role in the formation and strengthening of plant immunity, the ability to interact and defend for survival. It makes it stronger and more resistant to the pathogen and, if it is not produced, the plant dies. If the emergence of phytoalexins in the plant is suppressed and not working to its full potential, it will become vulnerable to various parasites that have not previously affected it.
When a parasite enters a plant cell, it receives a signal of “attack” and activates all forces for protection and healthy life. As a result, neighboring healthy cells produce phytoalexins as quickly as possible, which move and suppress the infected area, the necrotic zone. The parasites are deactivated, their growth and ability to destroy the plant dies.
Stimulation of phytoalexin production contributes to various biotic and abiotic agents. The use of chemicals can provoke its production, but not always the right concentration (or even several times higher) can lead to the death of the parasite.
Effect of monofertilizers on stimulation of phytoalexin production by plants
Phytoalexins promote antimicrobial activity and appear as a result of defense against infections, parasites and stress in a number of plants. They are the same within each family and have some differences between the plant kingdoms.
The chelated form of many fertilizers helps stimulate the synthesis of phytoalexins, natural phytoncides and help the plant actively fight parasites. The use of mono fertilizers in agriculture helps develop natural defenses of plant immunity, shows fungicidal effect on a wide range of pathogens. In addition, mono fertilizers help plants recover from stressful situations – frost, drought, sudden changes in temperature, pesticide application, adverse rainfall, etc.
Chelate fertilizers contain micro- and macronutrients that have a positive effect on plant growth and development. Since the absence or lack of one or another component makes the plant more vulnerable to external factors, physiological processes are disturbed and yields are reduced, experts recommend using mono fertilizers for most crops.
