title: [Effects of spatial coupling of watering and fertilization on winter wheat photosynthetic characteristics and grain yield].
abstract: A soil column experiment was conducted with a fertile Eum-Orthic Anthrosols to study the effects of spatial coupling of watering and nitrogen (N)- and phosphorus (P) fertilization on the photosynthetic characteristics and grain yield of winter wheat. The column consisted of three layers, each layer being 30 cm in thickness and with an underlying 2 cm layer of coarse sand to obstruct water- and nutrient exchange. The results showed that relative content of chlorophyll (SPAD), net photosynthetic rate (P(n)), and grain yield were significantly lower in the treatment of 0-30 cm soil drought and 30-90 cm soil wetness (D) than in that of 0-90 cm soil wetness (W). In these two watering treatments, a combined application of N and P got the highest SPAD, P(n) and grain yield, followed by applying P, and N. The SPAD, P(n) and grain yield were significantly higher when the fertilizer N was applied in 0-90 cm layer than in 0-30, 30-60 and 60-90 cm layers, respectively. No significant differences in SPAD, P(n) and grain yield were observed when fertilizer P was applied in 0-90 cm layer and in 0-30 cm layer. In treatment W, the SPAD, P(n) and grain yield were the highest when N and P were applied in 0-90 cm layer, had no significant differences with those when the N and P were applied in 0-30 cm layer, but were significantly higher than those when the fertilization was carried out in 30-60 and 60-90 cm layers. In treatment D, no significant difference in SPAD was observed when the N and P were applied in different layers, but P(n) and grain yield were significant higher when the N and P were applied in 0-90 cm than in 30-60 cm layer, and in 30-60 cm than in 60-90 cm layer. It was concluded that whether in treatment W or in treatment D, a combined application of N and P should be carried out in 0-30 cm soil layer.
authors.affiliation: State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau, Northwest A & F University, Yangling 712100, Shaanxi, China. shenyufang11@163.com
authors.forename: Yu-Fang
authors.initials: YF
authors.lastname: Shen
authors.forename: Shi-Qing
authors.initials: SQ
authors.lastname: Li
authors.forename: Ming-An
authors.initials: MA
authors.lastname: Shao
mesh_terms: D018533:Biomass; D005308:Fertilizers; D009584:Nitrogen; D010758:Phosphorus; D010788:Photosynthesis / Q000187:drug effects / Q000502:physiology*; D012621:Seasons; D014908:Triticum / Q000187:drug effects / Q000254:growth & development / Q000502:physiology*; D014867:Water / Q000494:pharmacology*
chemical_list: D005308:Fertilizers; D014867:Water; D010758:Phosphorus; D009584:Nitrogen