Humic acid: an auxiliary for promoting crop stress resistance
With the application of agricultural technology, the function of humic acid on crops has gradually been revealed. Too many functions are urgently needed to be excavated. The effect of humic acid on crop resilience has already appeared on the field, but how to promote crop reversal and how to improve the soil environment These issues are still not scientifically explained, and these studies are in the early stages.
- Improve the rhizosphere soil environment
The improvement of soil by humic acid is inseparable from its own physicochemical properties. The aqueous solution of humic acid is a hydrophilic sol, which exhibits a loose network structure in an aqueous solution, and thus has a strong water retention capacity, and has a certain adsorption effect on both organic substances and inorganic substances. Humic acid also reacts with clay minerals to form stable complexes, such as stable aggregate structure with soil calcium ions; strong cation exchange capacity, which can lower soil EC value and regulate pH. In addition, humic acid acts as a natural organic carbon source for microorganisms, which promotes the proliferation of microorganisms, thereby promoting the microenvironment of the rhizosphere, keeping the soil loose and maintaining root activity. Therefore, the physicochemical properties of the soil can be improved by humic acid, and the stress tolerance and stress resistance of the plant can be indirectly improved. For example, the study found that the application of humic acid products (Mei Ke-Yan Ke) on heavy saline-alkali soils in Inner Mongolia reduced soil total salt by 55.4%, pH by 0.3, and exchangeable sodium by 6.1%, improving soil structure and making crops normal. Growing.
2.Stimulate stress resistance gene expression
Humic acid can trigger the signal transduction reaction of cells, and a series of anti-reverse signals are targeted to downstream nuclei or other organelles, so that the specific gene expression levels are up- or down-regulated, leading to the response of downstream physiological synthesis or metabolic processes. In response to stress responses, promote growth and development. For example, the study found that humic acid products (Mei Ke-Yan Ke) can promote carotenoids under salt stress by stimulating carotenoid synthesis, chlorophyll synthesis, mineral element absorption, and hormone signaling. Chlorophyll synthesis, and regulates endogenous metabolism through hormone-mediated signaling effects, regulates endogenous levels of crops, regulates the absorption of mineral elements by crops, and enhances the salt tolerance of crops.
3.Improve crop antioxidant capacity
Humic acid has excellent effects on improving crops against drought, salinity, high temperature, low temperature, pest and disease stress. These effects are all caused by good bio-stimulation of humic acid, which will cause oxidative stress of crops and make crop cells The accumulation of reactive oxygen species (ROS) causes cellular oxidation, lipid peroxidation in the cell membrane, and ultimately cell death, showing physiological apoptosis of plants. Humic acid activates the activity of antioxidant enzymes in the cells and the synthesis of antioxidants, allowing cells to clear excess ROS and protect cell membranes. For example, humic acid products (Beautiful Ke-Yan Ke) can activate superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) activity and reduced glutathione in crops ( The content of GSH), carotenoids (Car), etc., activates the antioxidant system to remove excess ROS under salt-alkali stress, reduces the content of membrane lipid peroxidation product malondialdehyde (MDA), protects cell membranes, and protects crops against each Physiological oxidative stress caused by stress.
Humic acid also has certain chelation and complexation properties, and can react with metal ions and hydrated oxides, so that plants can more effectively use the nutrients in the soil; not only that, foliar application of humic acid can affect the stomata Open and close, so that the crops can better withstand environmental conditions such as high temperature and drought. Etc., humic acid is multi-faceted and balanced for crop resilience. From soil to crop itself, from abiotic stress to various types of biotic stress, from germination to fruiting, it can effectively and safely help crops resist bad habits.