Nutrient management strategies in Gansu province

IPNI-1999-CHN-GS4

13 May 2002

2001 Annual Interpretive Summary


Yield limiting factors of nutrients in soils on Gansu province, 2001

To determine yield-limiting, soil nutrient factors in Gansu province, four pot experiments with sorghum and four field experiments with corn were conducted in 2001 based on the PPI/PPIC ‘Systematic Approach’ to balanced fertilization. The test soil was irrigated desert soil from the Hexi Corridor, which is the important area for agricultural production in Gansu.

Preliminary results show nitrogen (N) and phosphorus (P) were the most limiting factors for corn production in the study region, while zinc (Zn) and copper (Cu) also limited corn yield. A field experiment in Wuwei showed 8 percent more corn yield when P application was increased from 100 to 150 kg P2O5/ha. Application of 9 kg Zn/ha resulted in a 6 percent yield increase. Soil from Wuwei showed a remarkable increase (500 percent) in sorghum biomass when supplied additional P. This soil was proven in the laboratory to have a high P adsorption (fixation) capacity. Further study is needed in order to give a reliable P recommendation for this type of soil.

There is a great potential for P consumption in the region. Crop responses to potassium (K) will be investigated in 2002. GANSU-NMS01