Nutrient management and balanced fertilization on main crops in Gansu province

IPNI-2006-CHN-GS3

23 Jan 2009

2008 Annual Interpretive Summary

Soil Nutrient Management and Balanced Fertilization in Gansu, 2008

In 2008, research on crop response to N, P, and K fertilizers, nutrient uptake, and nutrient use efficiency was investigated in spring corn, potato, and sunflower in the typically arid to semiarid climate of Gansu.
In sunflower at Wuwei County, comparisons between the balanced (OPT) treatment of 210-45-60 kg N-P2O5-K2O/ha, nutrient omission plots, and farmer practice suggest that K is the most limiting nutrient at the site and that the OPT can produce 240 kg/ha (10%) more seed yield than farmer practice.

A spring corn field trial at Zhenyuan County found P and Zn to be important for local corn production. The treatment of 325-150-135 kg/ha plus 6 kg Zn/ha produced the high yield of 10,870 kg/ha. This was 170 kg/ha more than identical treatment without Zn, 355 kg/ha more than treatment supplying 105 kg P2O5 + 6 kg Zn/ha, and 570 kg/ha more than treatment supplying 105 kg P2O5 + 3 kg Zn/ha. While these yield responses are small, they do show the value of Zn to the corn.

A corn trial at Dingxi County found application of 225-60-60 kg/ha to be most beneficial. The site was most limited by K and the high yield treatment generated 1,462 kg/ha (13%) more yield and US$240/ha more profit than the farmer practice of 150-120-0 kg/ha. Also in Dingxi, application of 210-60-60 kg/ha produced the best results in rainfed potato with significantly higher yields and profits than those obtained in each nutrient omission plot and the farmer practice (+8,867 kg/ha or 28%; +US$758/ha) of applying 150-120-0 kg/ha. Biomass and nutrient accumulation in different growing stages were also investigated. No significant differences were observed between KCl (potassium chloride) and K2SO4 (potassium sulfate) on potato yield.

Demonstrations of ASI soil test-based balanced fertilization in Wuwei indicated that the method could increase the yield of irrigated corn by 15 to 22% and increase income by US$479 to US$578/ha compared with farmer practice. In Dingxi, the method produced 15 to 58% more potato tuber yield and US$705 to US$1,628/ha more profit than farmer practice. Gansu-NMBF