title: Subsoiling practices change root distribution and increase post-anthesis dry matter accumulation and yield in summer maize.
abstract: Subsoiling is an important management practice for improving maize yield, especially for maize planted at high plant density. However, the affected physiological processes have yet to be specifically identified. In this study, field experiments with two soil tillage (CK: no-tillage, SS: subsoiling) and three planting densities (low: 45000 plants ha-1, medium: 67500plants ha-1, and high: 90000 plants ha-1) were conducted from 2010 to 2012 at Xinxiang, Henan province. Yield, canopy function, and root system were investigated to determine the associated physiological processes for improving maize production affected by soil tillage and plant density. Subsoiling significantly increased the grain yield of the low-, medium-, and high-planting densities by 6.21%, 8.92%, and 10.09%, respectively. Yield increase in the SS plots was mainly attributed to greater post-anthesis DMA and improved grain filling compared to CK plots. Greater green leaf area, leaf net photosynthetic rate, FV/Fm and ΦPSII in the SS plots were mainly contributed to enhanced dry matter production post-anthesis. This is mainly because subsoiling increased density of root dry weight in deep soil and root bleeding sap amount due to decreased the bulk density of the 0-30 cm soil profile layer. Density of root dry weight at 10-50 cm depth with SS increased by 40.68%, 32.17%, and 20.14% at low, medium, and high planting densities compared to CK, respectively, while the root bleeding sap amount increased by 17.41%, 15.82%, and 20.91%. These results indicate that subsoiling could change the root distribution and improve soil layer environment for root growth, thus maintaining a higher canopy photosynthetic capacity post-anthesis and in turn promoting DMA and yield, particularly at higher planting densities.
authors.affiliation: Institute of Crop Sciences, Chinese Academy of Agricultural Sciences / Key Laboratory of Crop Ecophysiology and Cultivation, Ministry of Agriculture, Beijing, China.
authors.forename: Xuefang
authors.initials: X
authors.lastname: Sun
authors.affiliation: Institute of Crop Sciences, Chinese Academy of Agricultural Sciences / Key Laboratory of Crop Ecophysiology and Cultivation, Ministry of Agriculture, Beijing, China.
authors.forename: Zaisong
authors.initials: Z
authors.lastname: Ding
authors.affiliation: Institute of Crop Sciences, Chinese Academy of Agricultural Sciences / Key Laboratory of Crop Ecophysiology and Cultivation, Ministry of Agriculture, Beijing, China.
authors.forename: Xinbing
authors.initials: X
authors.lastname: Wang
authors.affiliation: Institute of Crop Sciences, Chinese Academy of Agricultural Sciences / Key Laboratory of Crop Ecophysiology and Cultivation, Ministry of Agriculture, Beijing, China.
authors.forename: Haipeng
authors.initials: H
authors.lastname: Hou
authors.affiliation: Institute of Crop Sciences, Chinese Academy of Agricultural Sciences / Key Laboratory of Crop Ecophysiology and Cultivation, Ministry of Agriculture, Beijing, China.
authors.forename: Baoyuan
authors.initials: B
authors.lastname: Zhou
authors.affiliation: College of Agronomy and Biotechnology, China Agricultural University, Beijing, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Yue
authors.affiliation: Institute of Crop Sciences, Chinese Academy of Agricultural Sciences / Key Laboratory of Crop Ecophysiology and Cultivation, Ministry of Agriculture, Beijing, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Ma
authors.affiliation: Institute of Crop Sciences, Chinese Academy of Agricultural Sciences / Key Laboratory of Crop Ecophysiology and Cultivation, Ministry of Agriculture, Beijing, China.
authors.forename: Junzhu
authors.initials: J
authors.lastname: Ge
authors.affiliation: College of Agronomy and Biotechnology, China Agricultural University, Beijing, China.
authors.forename: Zhimin
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Institute of Crop Sciences, Chinese Academy of Agricultural Sciences / Key Laboratory of Crop Ecophysiology and Cultivation, Ministry of Agriculture, Beijing, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Zhao
mesh_terms: D018517:Plant Roots / Q000737:chemistry*; D012987:Soil; D003313:Zea mays / Q000737:chemistry / Q000254:growth & development*
chemical_list: D012987:Soil