Effects of Ginseng Cultivation in Farmland on Soil Physicochemical Properties and Maize Plants Nitrogen Uptake

【Objective】The study aims to investigate the impact of ginseng cultivation on soil quality improvement and plant growth and development of subsequent maize planting.【Method】Field experiments were conducted at four experimental sites of Beigang, Dafang, Choushui and Jingyu in Fusong County of Baishan City, Jilin Province. The13 physicochemical properties of the topsoil layer, dry matter accumulation of maize plants, as well as nitrogen uptake and utilization were investigated under two different farmland utilization methods, namely normal farmland (NF, as control) and improved farmland by ginseng planting (IFGP).【Result】The soil bulk density under soil depth layer of 10-20 cm and 20-30 cm under treatment of IFGP was ranged from 1.25 to 1.43 g/cm3, which was significantly lower than that of the control(NF). The averaged thickness topsoil layer in the position of the ridge and furrow was 31.4 cm and 16.94 cm, which were 89.6%-93.55% and 39.59%-56.52% higher than the NF, respectively. For the nutrients content in the topsoil, the organic matter, total nitrogen, alkali hydrolyzable nitrogen, and available potassium content in the four experimental sites were increased by 6.18%-38.99%, 2.68%-12.64%, 6.62%-42.90%, and 6.39%-40.54% under treatment of IFGP, respectively, compared to NF. In addition, the range of soil pH in the treatment of IFGP was 4.8-6.82, which significantly improved the trend of soil acidification compared to NF. Compared with NF, except for the result of Jingyu, the dry matter accumulation of maize plants in the other three experimental sites were increased by 14.70%, 11.19%, and 10.32%, respectively. The increase in maize grain yield was ranged from 8.56% to 14.08%, and the increase mainly due to the increase in effective ears per unit area. The nitrogen (N) content in organs such as leaves and grains in maize plants at harvesting stage under treatment of IFGP was significantly higher than that of NF, resulting in 13.60%-26.08% increase of total N absorption of whole maize in IFGP as compared to the NF. Correlation and regression analysis showed that the dry matter accumulation in maize plants was positively correlated with soil available nitrogen and organic matter content, and a significant linear relationship between soil total nitrogen content and grain N concentration were also observed.【Conclusion】IFGP treatment can significantly improve the nutrient status, increase the thickness of the topsoil layer, reduce the soil compaction, which is benefit to the growth and development of post maize. In addition, the increase in N levels in farmland after ginseng cultivation is conducive to the increase in maize yield and soil N absorption and utilization