Abstract: It is very important to elucidate temporal-spatial distribution of soil available phosphorus(P) content, P uptake and soil P apparent surplus amount to better utilize P fertilizer.In this study, by using two cultivars of wheat (Triticum aestivum L.cv Ningmai 9 & cv Yumai 34), field experiments with different nitrogen applications (0 kg/ha and 1:9, 3:7, 5:5, 7:3 at 225 kg/ha) were conducted in Nanjing during 2010 and 2011.The results showed that P uptake peak was from jointing to anthesis, and the treatment N5/5 reached the highest.Soil available P content in 0-40 cm soil layer decreased with the increase of basal nitrogen fertilizer application before jointing, and was the lowest when the basal to topdressing fertilization ratio was at 5:5 after jointing.Soil P surpluses and deficits were obviously linked to growth-stage features.P surplus occurred from sowing to jointing, and P deficit occurred from jointing to maturity.During the whole growing season, P apparent surplus was the lowest when the basal to topdressing nitrogen fertilization ratio was at 5:5, and the highest when the basal to topdressing nitrogen fertilization ratio was at 1:9.It can be concluded that Ningmai 9 and Yumai 34 reduced P₂O₅ rate 6.5 and 8.4 kg/ha at 105 kg/ha respectively, combined application of 225 kg/ha (the basal to topdressing fertilization ratio was 5:5), which could improve grain yield and reduce loss of P in wheat production.

Key words: Nitrogen applications, Wheat following rice, Phosphorus accumulation, Soil available phosphorus, Phosphorus balance

CLC Number: 

• S143.1