8th INTERNATIONAL WHEAT CONFERENCE

yIeLd gAPS, SoIL INdIgeNouS NuTRIeNT SuPPLy, ANd
NuTRIeNT uSe effICIeNCy of WheAT IN ChINA
Ping HE
China Program, International Plant Nutrition Institute(IPNI) and Institute of Agricultural
resources and Regional Planning, Chinese Academy of Agricultural Sciences, 12 South
Zhongguancun Street, Beijing, 100081, China.
E-mail Address of presenting author: phe@ipni.net
Before any improvements on crop management practices have been made, it is of great
importance to know the the attainable yield (Ya) of the crop in the region, and the yield gap
between Ya and the actual yield obtained by the growers. Analysis of the soil indigenous
nutrient supply and nutrient use efficiency of wheat will help to bridge the yield gap due
imbalance nutrient management. Based on the data of field experiments in different wheat
growing-regions and a number of data published in the literatures from 1995 to 2008, the
yield gaps, soil indigenous nutrient supplies, and nutrient use efficiency of wheat in China
were analyzed. The attainable yield (Ya) in this study was proposed to the weather limited
yields that can be achieved with current best manage practices. The actual yield in farmer’s
fields always lower than (Ya) due to inefficient use of fertilizer nutrient. Average Ya of wheat
grown in the whole China was 6695 kg ha –1 . There were significant differences of Ya among
different regions in China. The Ya obtained followed the order of North-central China (7129
kg ha –1 )> the Lower reaches of the Yangtze River (7023 kg ha –1 )> Northwest China (5089
kg ha –1 )>Southwest China (5023 kg ha –1 ) >Northwest China (3480 kg ha –1 ). The yield gap
between Ya and the actual yield obtained by the farmers (YFP) was averagely 870 kg ha –1
across field types and localities, which was about 13% of Ya. The yield gap between Ya and the
actual yield due to no fertilizer supply was wider, averaged by 2515 kg ha –1 , and ranged from
171 kg ha –1 to 5552 kg ha –1 , which was about 33% of Ya. The average yield gap-N (due to no N
supply) was 1928.3 kg ha –1 , ranged 974–3240 kg ha –1 accounting for 50% of all the cases. The
average yield gap-N was about 29% of Ya. The average yield gap-P (due to no P supply) was
989 kg ha –1 , ranged 475.4 –1 272.0 kg ha –1 accounting for 50% of all the cases. The average yield
gap-P was about 14.8% of Ya. The average yield gap-K (due to no K supply) was 923.4 kg ha –1 ,
ranged 440.6 –1 330.2 kg ha –1 account for 50% of all the cases. The average yield gap-K was about
13.8% of Ya. Yield gap caused by no nutrient supply was following the order of N>P>K.
The amount of N derived from indigenous resources varied from 37.8 to 275.2 kg N ha –1 ,
and averaged by 120.9 kg N ha –1 . The amount of P derived from indigenous resources ranged
6.4–59.8 kg P ha –1 , and averaged by 27.4 kg P ha –1 . The amount of K derived from indigenous
resources wheat ranged from 36.9–357.0 kg K ha –1 , and averaged by 133.0 kg K ha –1 .
Apparent recovery efficiency (RE) of N, P and K were 38 % (n=333), 17 % (n=99) and 30 %
(n=120) respectively. RE of N, P and K decreased by 7, 5 and 17 percentage point than that
in 1985-1995, respectively. The agronomy efficiency (AE) of N, P and K in optimal nutrient
management practices were 10.6 (n=559), 22.3 (n=294) and 9.2 (n=593) kg kg
45
-1 , respectively.
The most commonly distributed (from 25% to 75%) AE values ranged from 5.2–14.9 kg kg-1 for N, 10.7–29.4 kg kg-1 for P and 4.5–11.9 kg kg-1for K for wheat in China.