Mineral humic acid is a natural green plant growth promoter that can effectively stimulate the growth of plant roots and promote plant roots to absorb nutrients.
The promotion effect of mineral humic acid on plant root nutrient absorption is mainly reflected in the absorption of nitrate.
On the one hand, mineral humic acid can promote the expression of genes related to nitrate absorption and assimilation in plant roots. Studies have shown that under the action of low molecular weight humic acid, genes related to nitrate absorption (NRT2.1 and MHA2) and nitrate assimilation genes (NR1) in corn roots showed up-regulated expression.
On the other hand, mineral humic acid can stimulate plants’ absorption of nitrate by regulating the internal environment of plant roots. Mineral humic acid can reduce the pH on the surface of the root cell plasma membrane, neutralize the alkali produced by NO3- as a nitrogen source, and inhibit the co-transfer of H+/NO3-; mineral-source humic acid (especially small molecular weight humic acid) has a negative effect on the plasma membrane. The stimulation of isolated H+-ATPase activity determines the increase in the electrochemical proton gradient, thereby promoting the absorption of NO3- by plant roots, and ultimately the absorption of nitrogen by plants. Therefore, humic acid from mineral sources can promote plant absorption of nitrate nitrogen by regulating the absorption, assimilation and transfer of nitrate. In addition, mineral humic acid can also promote the absorption of nutrient ions such as SO42- and K+ by barley and oat seedlings.
Mineral humic acid can also be absorbed by plants as nutrients. Mineral humic acid (especially small molecular weight humic acid) can easily reach the cytoplasmic membrane of higher plants and is partially absorbed by the plants; researchers conducted sand cultivation experiments using X-labeled mineral humic acid and also observed that mineral-source humic acid can Entering the plant through a cut surface of the root or stem.
In summary, mineral humic acid can significantly promote the absorption of nutrients by plant roots, thereby promoting plant growth.