Salicylic acid (SA) chemical name o-hydroxybenzic acid, a type of small molecular phenolic substance widely found in plants, is an intermediate product of the phenylalanine metabolic pathway and is a derivative of cinnamic acid.
Salicylic acid is low in price, non-toxic and harmless, and very convenient to use, and its non-toxic characteristics are in line with the development trend of modern agriculture, so it can be widely used in agriculture.
In addition, salicylic acid can be used as an additive adding to the agricultural formulation that can increase crop yields, improve crop quality, increase crop resistance, and enhance the competitiveness of agricultural products in the market.
Mechanism of Salicylic Acid in Agriculture
1. Salicylic acid induce plant disease resistance
The salicylic acid receptor protein gene in plants is highly homologous to the peroxidase gene. Exogenous salicylic acid can directly activate the activities of many resistance-related enzyme systems when entering the body; at the same time, salicylic acid is also involved in the metabolism of jasmonic acid in plants Regulation, the latter can enhance the plant’s resistance to various stresses.
2. Salicylic acid induce plant cold tolerance
Under low-temperature stress conditions, salicylic acid can accumulate in the hydrophobic area of the cell membrane, affecting a series of physiological and biochemical reactions related to the membrane.
Increase the concentration of the solute in the cell, improve its osmotic regulation, and alleviate the changes brought by the cold stress to the cell, such as biofilm phase change and electrolyte extravasation, thereby relatively improving cold tolerance.
Application of Salicylic Acid in Agricultural Production
1. Salicylic acid induces flowering: Salicylic acid is related to the induction of flowering. Among them, the effect of inducing flowering on many ornamental plants provides new ideas for the physiological regulation of horticultural plants.
2. Promote high-quality and high-yield crops: Treating crops with low-concentration salicylic acid significantly enhances anabolism, increases grain weight and the number of grains, increases yield, and improves quality.
3. External application of salicylic acid can increase the resistance and tolerance of crops to adversity: most plants include rice, corn, wheat, rape, tomato, kidney beans, cucumber, garlic, soybeans, sugar beet, and tobacco, etc. After the application of salicylic acid, It has a certain effect on improving the salt, drought, and cold resistance of crops.
4. Improve the cold tolerance of crops: Early rice seedlings are vulnerable to low temperature and cold damage, and exogenous salicylic acid can reduce the damage of low-temperature stress to rice.
5. Improve fruit storage: After salicylic acid treats apples, cell membrane permeability and malondialdehyde content are reduced, respiration rate is significantly reduced, and fruit senescence is delayed. Research on pears, peaches, oranges, and other fruits has similar results. This may be related to the ability of salicylic acid to inhibit the production of ethylene.
6. Effect on fresh cut flowers: Salicylic acid has a certain effect on fresh flowers, and can obviously inhibit the growth of bacteria. After the rose is treated, the flower opening time is significantly prolonged.
7. Induce the formation of female flowers: spraying salicylic acid can reduce the number of male flowers in cucumbers and induce the formation of female flowers.