Field validation of Nutrient Expert for single season rice in China

Nutrient Expert Rice was developed to evaluate and validate fertilizer recommendation method based yield response and agronomic efficiency as compared with soil testing and farmer's practice


02 Jun 2018

2017 Annual Interpretive Summary

Nutrient Expert® (NE) field validation continued for single-season rice in 2017 through 10 on-farm experiments in Jilin and Heilongjiang Provinces of China. The objective was to compare the NE-based fertilizer recommendation method with traditional soil test-based fertilizer recommendations and farmers' practice (FP), in terms of rice grain yield and nutrient use efficiency.

Each individual field site received a site-specific fertilizer application based on the NE tool and soil test results. The average nutrient application rates in the NE-based plots were 171-61-98 kg N-P2O5-K2O/ha, the soil test-based plots received an average of 167-63-84 kg/ha, while the FP plots received 175-63-71 kg/ha in Heilongjiang Province. Average rice grain yield in the NE treatment (9.3 t/ha) was higher than the soil test (8.8 t/ha) and FP treatments (8.1 t/ha), but the values were not significantly different. The average agronomic efficiency (AE) and partial factor productivity (PFP) of nitrogen were 22.9 kg/kg and 54.4 kg/kg in the NE treatment, 20.5 kg/kg and 53.0 kg/kg in the soil test-based treatment, and 15.9 kg/kg and 47.6 kg/kg in the FP treatment, respectively.

For Jilin Province, the average N-P2O5-K2O application rates were 167-65-94 kg/ha in the NE-based plots, 176-69-93 kg/ha in the soil test-based plots, and 182-74-92 kg/ha in the FP plots. There was no significant difference in rice grain yield between the NE (8.8 t/ha), soil test (8.8 t/ha) and FP treatments (8.6 t/ha). Similarly, the AE and PFP values of nitrogen among the treatments were not different.

The NE tool provided fertilizer recommendations that improved yield and nutrient use efficiency in single-season rice and it could be useful when soil testing is not available or timely.