Changes in Phosphorus Requirement with Increasing Grain Yield for Winter Wheat. (1st November 2015)

• Record Type: Journal Article
• Authors: Zhan, Ai; Chen, Xinping; Li, Shiqing; Cui, Zhenling
• Is Part Of: Agronomy Journal. Volume 107:Number 6(2015)
• Page Start: 2003
• Page End: 2010
• Publication Date: 2015-11-01
• Subjects: Agronomy -- Periodicals; 630
• DOI: 10.2134/agronj15.0089
• Languages: English
• ISSNs: 0002-1962

Abstract

Abstract : Overestimation of the P requirement has been a driving force in the overuse of P fertilization in intensively managed agricultural systems and the resulting extensive environmental pollution. A database comprising 2157 measurements was developed from 2000 to 2013 using 45 on‐farm and station trials to evaluate the relationship between aboveground P uptake and grain yield with different P fertilizer (Pf ) treatments and to quantify P requirements per megagram of grain at different grain yield levels. Winter wheat ( Triticum aestivum L.) yield ranged from 0.9 to 11.7 Mg ha −1 . The P requirement per megagram of grain yield (Preq ) increased with Pf supply from 4.1 kg under the treatment without Pf to 4.8 kg under the Pf surplus treatment. These results imply that excessive P application generally does not lead to greater P use efficiency and poses a potential environmental threat. Under the optimal Pf (Pf = Opt) treatment, the average Preq was 4.5 kg, and it declined from 4.7 kg in the yield range of <4.5 Mg ha −1 to 4.2 kg in the yield range of >9 Mg ha −1 due to the increasing harvest index (from 45.7 to 48.2%) and the diluting effect of declining grain P concentrations (from 3.8 to 3.2 g kg −1 ). The largest variation in shoot biomass and P accumulation under Pf = Opt treatment occurred from the stem elongation to anthesis growth stages, suggesting that, in addition to Pf supply, crop management during the early growth season is also important for achieving higher yields.