As a new type of natural mineral source active potassium fertilizer, potassium fulvic acid is widely used in agriculture and horticulture. Its series of functions can greatly promote plant growth. This article will focus on the role of potassium fulvicate – regulating the activity of soil microorganisms and enzymes, and explain the role and mechanism in detail.
The humic acid contained in potassium fulvic acid is an important component of soil humus. It has a stable carbon form and plays a key regulatory role in the quantity and diversity of soil microorganisms. Research shows that when sorghum uses potassium fulvic acid, the number of rhizosphere soil bacteria at the heading stage is 45.58% higher than that of sorghum treated with chemical fertilizers, and the number of soil fungi is 23.26% higher than that of sorghum treated with chemical fertilizers. Applying potassium fulvic acid can improve the activities of soil urease and phosphatase, increase the timeliness of soil effective nutrients, and improve plant nutrition.
Research data shows that potassium fulvicate can inhibit the community composition and quantity changes of ammonifying bacteria, ammonifying archaea and other microorganisms in the soil by reducing the hydrolysis rate of urea to ammonia in the soil and buffering the soil pH. The application of buffered urea has an impact on the soil. The promotion of cell diversity reduces the rate at which ammonia is oxidized into nitrite and nitric acid, and reduces the loss caused by denitrification into nitrogen. Ultimately, more nitrogen can be absorbed and utilized by plants, thereby promoting plant growth.
In addition, potassium fulvicate can also increase the activity of ribulose diphosphate oxygenase/carboxylase in crops by increasing cellular respiration and cell membrane nutrient absorption, increasing plant photosynthetic activity, and improving the biological efficiency of leguminous crops. Nitrogen fixation activity, etc., thereby promoting crop growth and increasing crop yields.
Potassium fulvicate can also improve the soil by regulating soil enzyme activity, providing favorable conditions for the growth of plant roots and the preservation of fertilizer nutrients. For example, potassium fulvic acid can inhibit the activity of soil urease in the early stage of application, reduce the hydrolysis rate of urea, and thereby reduce the volatilization of ammonia, the hydrolyzate product, because the large number of unsaturated bonds in potassium fulvic acid can effectively prevent the oxidation of the active mercapto functional groups in urease. On the other hand, potassium fulvicate can also chelate Cu2+ and Hg2+, inhibitors of the urease base in the soil. It can stabilize the urease activity in the later stages of addition, allowing urea to continue to be converted into ammonia at a relatively stable rate to supply plant growth.
