Effects of boric acid on urea‐N transformation and 3,4‐dimethylpyrazole phosphate efficiency

Abstract

Background3,4‐Dimethylpyrazole phosphate (DMPP) is a nitrification inhibitor which can restrict nitrate (NO3−) production. Boric acid is a substance which inhibits urease activity. However, few studies have focused on the inhibitory effect of boric acid on urea hydrolysis and the possible synergistic effect with DMPP. Thus, an incubation trial was conducted to determine the impact of boric acid and DMPP addition on urea‐N transformation, and their synergistic effects, in chernozem soil (Che) and red soil (RS). Four treatments were set up in each soil: urea only (U); urea combined with DMPP (UD); urea combined with boric acid (UB); and urea combined with both DMPP and boric acid (UDB).ResultsCompared to U, adding DMPP (UD) increased NH3 emissions by 11% and 13% and decreased soil NO3−‐N concentration by 38% and 13% in Che and RS, respectively. Boric acid addition (UB) effectively prolonged the half‐life time of urea by 0.8 and 0.4 days, reduced NH3 volatilizations by 11% and 16% and delayed the occurrence of NH3 emission peaks for 3 and 4 days in contrast to U treatment in Che and RS, respectively. UDB treatment mitigated the NH3 volatilizations caused by the addition of DMPP (UD) by 16% and 29% in Che and RS, respectively. Additionally, a better nitrification inhibition rate was found in the UDB treatment compared to other treatments in both soils.ConclusionsThere is potential to develop a new N transformation inhibition strategy with the use of a combination of boric acid and DMPP. © 2020 Society of Chemical Industry

Enriching Urea with Nitrogen Inhibitors Improves Growth, N Uptake and Seed Yield in Quinoa (Chenopodium quinoa Willd) Affecting Photochemical Efficiency and Nitrate Reductase Activity

“…These leaching and denitrification losses can be minimized by nitrification inhibitors which limit oxidation of NH 4 + to NO 3 − by reducing the activity of nitrifying bacteria [ 20 , 21 ], however, retention of NH 4 + by application of these inhibitors may further increase risk of volatilization [ 22 , 23 ]. Likely, boric acid has the potential to inhibit urease activity in soil [ 24 ]. While ammonium thiosulphate (ATS) as a good source of N and sulphur (S) for plants has the potential to inhibit both hydrolysis and nitrification without harming the soil microbial pool [ 25 ].…”

“…The combined application of NIs reduces multiple losses associated with volatilization and denitrification [ 26 , 27 ] had been found to improve yield 5.7 and 8.0% of N uptake in rice [ 28 ], 22–36% increase in biomass and 23–32% of N uptake in pasture [ 29 ]. The combined application of different inhibitors, for instance, boric acid and 3, 4-Dimethylpyrazole phosphate (DMPP), urease and nitrification have also the potential to inhibit the N transformation synergistically [ 24 ], increase yield by 7.5% and NUE by 12.9% especially at low N dose [ 30 , 31 ], respectively. Nonetheless, these increases in N uptake and yield were associated with reduced losses of N and environmental footprints [ 24 , 28 , 29 , 30 , 31 ].…”

“…The combined application of different inhibitors, for instance, boric acid and 3, 4-Dimethylpyrazole phosphate (DMPP), urease and nitrification have also the potential to inhibit the N transformation synergistically [ 24 ], increase yield by 7.5% and NUE by 12.9% especially at low N dose [ 30 , 31 ], respectively. Nonetheless, these increases in N uptake and yield were associated with reduced losses of N and environmental footprints [ 24 , 28 , 29 , 30 , 31 ].…”

Valorization of Polyphenols from Stryphnodendron adstringens Bark for Use as a Sustainable Inhibitor of Nitrogen Volatilization in Soil

“…However, NPBT only becomes an effective inhibitor when it is converted to N-( n -butyl)­phosphoric triamide (NBPTO) . Moreover, recent findings indicate that NBPT does not have sufficient characteristics for agricultural application due to its lack of compatibility with nitrification inhibitors and a high rate of toxicity to plants, especially in roots. − …”