[Phosphorus use efficiency of wheat on three typical farmland soils under long-term fertilization].

Field experiments were conducted on three typical farmland soils(loess soil,fluvo-aquic soil,and cinnamon fluvo-aquic soil)in Northern China to study the grain yield,phosphorus agronomic efficiency(PAE),and phosphorus use efficiency(PUE)of wheat under effects of long-term fertilizations.Seven treatments were installed,i.e.,non-fertilization(CK),nitrogen fertilization(N),nitrogen-potassium fertilization(NK),nitrogen-phosphorus fertilization(NP),nitrogen-phosphorus-potassium fertilization(NPK),NPK plus straw returning(NPKS),and NPK plus manure application(NPKM).The averaged wheat grain yields under long-term P fertilizations(treatments NP,NPK,NPKS,and NPKM)ranged from 2914 kg·hm-2 to 6219 kg·hm-2,being 200%-400% higher than those under no P fertilizations(treatments CK,N,and NK),and no significant differences were observed between the P fertilizations.In the early years of the experiment,the PAE in treatment NPK on the loess soil,fluvo-aquic soil,and cinnamon fluvo-aquic soil was 17.0 kg·kg-1,20.3 kg·kg-1,and 13.3 kg·kg-1,and the PUE was 15.3%,31.2%,and 23.8%,respectively.After 15-year fertilization,the PAE and PUE in treatment NPK increased annually by 3.9 kg·kg-1 and 1.3% on loess soil,2.5 kg·kg-1 and 0.9% on fluvo-aquic soil,and 2.8 kg·kg-1 and 1.0% on cinnamon fluvo-aquic soil,respectively.There were no significant differences in the PAE and PUE among the P treatments for the same soils.In Northern China,long-term P fertilization could increase the wheat grain yield and PUE significantly,and the mean annual increase of PAE and PUE in treatment NPKM was higher on loess soil than on fluvo-aquic soil and cinnamon fluvo-aquic soil.