Research progress of biological nitrification inhibitor (BNI) in improving nitrogen use efficiency in agricultural production systems

Fertilization is one of the main methods to improve agricultural productivity. Improving nitrogen use efficiency is one of the core issues in chemical fertilizer application. Nitrate-nitrogen leaching and nitrous oxide (N₂O) emissions caused by nitrification and denitrification are the main reasons for low nitrogen utilization rate, and N₂O is a greenhouse gas that causes a sharp rise in global temperatures. Biological nitrification inhibition refers to the ability to release a natural compound that inhibits nitrification from the roots of plants. The released natural compound is called a Biological nitrification inhibitor (BNI), which specifically inhibits the activity of microorganisms in soil nitrification. BNIs can significantly increase the yield of rice, corn, and other crops by approximately 5%～10% and corn utilization of nitrogen by 3.1%, as well as decrease emission of greenhouse gases, such as N₂O, by 90% compared to those in non-BNI plants. The BNI “Brachialactone”, which is released by Brachiaria plants, exerts nitrification-inhibitory effect, inhibiting 60%～90% of the total nitrification. The above findings show that BNIs play an important role in inhibiting nitrification, increasing nitrogen utilization, increasing crop yield, and decreasing greenhouse gas emission. This paper reviews the plants known to release BNIs and plants known to inhibit soil nitrification but with unknown BNIs, and further discusses the important role of bio-nitrification inhibition in agricultural systems.