Nutrient management and balanced fertilization in Inner Mongolia

IPNI-2006-CHN-NM1

11 Feb 2010

2009 Annual Interpretive Summary

Nutrient Management and Balanced Fertilization in Inner Mongolia, 2009

Field experiments were conducted on rainfed and irrigated potato, oil sunflower, and rapeseed to document nutrient accumulation and yield response.

In flood-irrigated potato at Wuchuan County, application of 210-90-165 kg N-P2O5-K2O/ha produced 19.1%, 11.6%, and 4.0% more tuber yield over N, P, and K omission plots, respectively. A similar potato trial in Chayouzhong Qi was more responsive and produced 32.9%, 37.4%, and 35.1% more yield over omission plots when 210-150-150 kg N-P2O5-K2O/ha was applied. Similarly, sprinkler-irrigated potato in Chayouzhong Qi receiving 300-150-225 kg N-P2O5-K2O/ha obtained 28.7%, 34.7%, and 32.7% more yield over N, P, and K omission plots. Yields under flood-irrigated potato were similar (36 t/ha) in Wuchuan and Chayouzhong Qi. Yield under the sprinkler-irrigated sites reached 60 t/ha. Nutrient use efficiency under sprinkler irrigation was 30% higher than under flood irrigation. Experiments on sunflower for oil demonstrated high seed yields under the selected optimum (OPT) of 210-75-150 (Hangjinhouqi), 240-105-105 (Wuyuan), and 285-120-150 kg N-P2O5-K2O/ha (Daqi). Across these sites, the average agronomic efficiency (kg seed increase per kg added nutrient) for these OPTs was 4.0 (N), 3.5 (P2O5), and 6.5 (K2O). Average recovery efficiency for applied N, P, and K was 47%, 22%, and 45%. About 6.1 kg N, 2.2 kg P2O5, and 4.1 kg K2O was required to produce 100 kg sunflower seed. Experiments in oilseed rape have been conducted in Wuchuan County for 7 years. Average agronomic efficiency for an average OPT (90-43-45 kg N-P2O5-K2O/ha) was 4.1 (N), 6.8 (P2O5), and 5.1 (K2O). Recovery efficiency for applied N, P, and K was 30%, 15%, and 49%. About 6.1 kg N, 1.9 kg P2O5, and 4.6 kg K2O was required to produce 100 kg rapeseed. Inner Mongolia-NMBF