Effect of the combination of nitrapyrin and gamma-aminobutyric acid on soil nitrogen transformation characteristics and rice yield

When 2-chloro-6-(trichloromethyl) pyridine (nitrapyrin) is applied alone, it typically does not significantly increase crop yield. Therefore, we combined gamma-aminobutyric acid (GABA) with nitrapyrin to address the limitations of nitrapyrin in enhancing yield. We conducted indoor incubation experiments and pot experiments in Chernozem and Calcic Kastanozem, respectively. The results demonstrated that GABA exerted an influence on the effectiveness of nitrapyrin by altering its degradation rate. In Chernozem, GABA accelerated nitrapyrin degradation, whereas, in Calcic Kastanozem, the results were the opposite. The pot experiment results showed that the combination of nitrapyrin and GABA increased rice total biomass by 5%, grain yield by 18 ± 2%, and plant nitrogen (N) uptake by 9 ± 1% compared to nitrapyrin applied alone. The increase in yield was attributed to the combined effect of nitrapyrin and GABA, which elevated root biomass and leaf area. In contrast, the effect of GABA on yield through altering the degradation rate of nitrapyrin was weaker. Therefore, the combination of nitrapyrin and GABA combined with urea increases rice yields in Chernozem and Calcic Kastanozem. The aim of this endeavour was to foster the development of a novel fertiliser product that offers both favourable agronomic outcomes and environmental benefits.