A. What are the effects and functions of amino acid fertilizers?
a. Effects
(1) Enhanced resistance: After application, a large number of beneficial microorganisms will form an effective protective layer on the crop roots and secrete resistance factors, improving the crop’s resistance to adverse conditions. The microorganisms contained in amino acid fertilizers can inhibit or kill harmful bacteria in the soil to a certain extent, which has a certain effect on resisting continuous cropping.
(2) Balanced nutrition: Amino acid fertilizers are rich in beneficial bacteria, amino acids, trace elements, and other nutrients. The trace elements (such as zinc, molybdenum, copper, iron, manganese, boron, etc.) exist in a chelated state, which can be effectively absorbed and utilized by crops. Amino acid fertilizers have balanced nutrients and a reasonable formula, which can meet the nutrient needs of crops at different stages.
(3) Relief from pesticide damage: The polypeptides and biological enzymes contained in amino acid fertilizers have an oxidation-reduction effect on residual pesticides. Through dealkylation, deoxygenation, and dehalogenation, pesticides can be converted into non-toxic substances. (4) Promotes growth: The bioactive peptides in amino acid fertilizers can promote crop root growth, encourage seedlings to develop rapid root growth and more secondary roots, thereby enhancing the crop’s ability to absorb water and nutrients, resulting in robust plant growth.
(5) Increases yield and maintains quality: Amino acid fertilizers are rich in micronutrients and bioactive factors. After application, they can enhance crop photosynthesis, promote growth, increase yield, and improve quality.
(6) Inhibits salinity: The metabolic products of beneficial microorganisms in amino acid fertilizers (such as polypeptides, enzymes, organic acids, and other active ingredients) combine with soil salinity, reducing salinity and generating nutrients beneficial to crops.
b. Effects
(1) Increases the number of beneficial bacteria
Applying amino acid fertilizers can increase the number of actinomycetes, fiber-decomposing bacteria, and aerobic bacteria, thereby accelerating the mineralization of organic matter and promoting the release of nutrients.
(2) Enhancing the Effectiveness of Fertilizers
① Adding amino acids to fertilizers can enhance their chemical and biological activities, such as adsorption, chelation, combination, and microbial reproduction, thereby improving fertilizer utilization.
② Amino acids have multifaceted effects on potential nitrogen in the soil. Due to their stimulating effect, amino acids can increase the viability of soil microorganisms, accelerate the mineralization of organic nitrogen, and have a high base exchange capacity, thus reducing nitrogen volatilization and loss, and to a certain extent increasing the content of available nitrogen in the soil.
③ Amino acids have a significant effect on the decomposition of phosphate rock and a protective effect on available phosphorus. After application, they can reduce the fixation of available phosphorus in the soil, promote the absorption of phosphorus by crop roots, and increase the utilization and absorption rate of phosphate fertilizer.
④ The acidic functional groups of amino acids can absorb and store potassium ions, preventing potassium ions from being lost with water in soils with high leaching and sandy soils, while also preventing potassium ions from being fixed in clay soils. Amino acids have a dissolving effect on potassium-containing minerals such as potassium feldspar and silicates, gradually decomposing them and increasing the release of potassium, thereby increasing the content of readily available potassium in the soil.
B. What are the differences between amino acid fertilizers and humic acid fertilizers?
a. Different types
(1) Amino acid fertilizers: Amino acid foliar fertilizers are organic-inorganic compound (chelated) water-soluble fertilizers, mostly manufactured using chelation processes. They contain more trace elements, and the higher the chelation value, the better the crop’s absorption and utilization rate of the fertilizer. For example, the absorption and utilization rate of high-efficiency molar foliar fertilizers can generally exceed 95%. After applying amino acid foliar fertilizers to crops with peak fertilizer requirements in the middle and late stages, significant effects such as fruit expansion, coloring, early maturity promotion, and improved quality can be achieved in about 7 days.
(2) Humic acid fertilizer: This is an organic-inorganic compound (chelated) water-soluble fertilizer. For farmland that has long used chemical fertilizers, using humic acid fertilizer can improve the resulting soil compaction, decreased fertility, and low yield despite high topdressing. This type of fertilizer can also loosen the soil, quickly adjust soil structure, and allow plants to better absorb nutrients from the soil.
b. Different characteristics
(1) Amino acid fertilizer: This is a nitrogen-containing fatty acid with a small molecular weight.
(2) Humic acid fertilizer: This is an organic carboxylic acid in the macromolecular aromatic group.
c. Different functions
(1) Amino acid fertilizer: It can significantly improve the absorption and conversion rate of nutrients by crops, and also enhance the crop’s resistance to stress and disease.
(2) Humic acid fertilizer: It can quickly activate the soil, adjust the soil pH, promote crop metabolism, enhance photosynthesis, increase fruit setting rate and single fruit weight; it can also prevent flower and fruit drop and avoid crop infection by pests and diseases. In addition, it can extend the harvesting period and shelf life of agricultural products, and alleviate some diseases caused by the application of herbicides.
