Abstract
Mechanical grain harvesting is a crop production development direction. However, the residue management methods suitable for mechanical grain harvesting have been not established. In order to study the effect of residue management modes on maize yield formation and explore the best residue management methods for mechanical grain harvesting, four crop field surveys were carried out in Southwest China. Crops were mechanically harvested, and the residues were shredded and returned to the field using various straw application methods including straw deep burial with plowing (SDBP), straw shallow burial with rotary tillage (SSBRT), and straw mulching with minimum tillage (SMMT). The first-season rape residues were returned to the field, and the second-season maize yield under SDBP and SSBRT was significantly higher than that under SMMT. However, with the increase in rounds of residue application, compared with SDBP and SSBRT, SMMT continuously increased the soil moisture content in the 0–30 cm soil layer at the early stage of maize growth, increased the soil alkaline-hydrolyzed nitrogen content in the 0–20 cm and 40–60 cm layers, and reduced the soil compaction under 40 cm layer, which were more conducive to the root system growth. Maize yield with the SMMT increased by 5.4% compared with that of the previous season, while the yields with SDBP and SSBRT decreased by 16.7% and 12.7%, respectively, compared with those of the previous season. In conclusion, it is recommended to employ the SMMT method during crop mechanical harvesting, which is of great significance to improve soil quality and increase maize grain yield.
Highlights
Previous studies have pointed out that the long-term application of conventional farming methods and removing crop residues have severely disturbed and destroyed the natural structure of the soil, resulting to a continuous decline in the soil organic matter content, which restricts the increase of crop grain yield [1]
After the first straw application, the maize yields using the straw deep burial with plowing (SDBP) and straw shallow burial with rotary tillage (SSBRT) were higher than that using the straw mulching with minimum tillage (SMMT) by 26.8% and 17.7%, respectively
Compared to the first maize harvest, with the increase in rounds of mechanical harvesting and straw application, the yields with the SDBP and SSBRT were reduced by 16.7% and 12.7%, respectively, whereas the yield using the SMMT was increased by 5.4%. e increase in yield was mainly a result of the increase in biomass, i.e., the harvest indices were barely changed. e yield of latematuring cultivar Baoyu 9 (BY9) was significantly higher than the earlymaturing cultivar Jinyu 99 (JY99) (8.4% and 7.7%, respectively), mainly due to the higher biomasses and harvest indices of BY9
Summary
Previous studies have pointed out that the long-term application of conventional farming methods and removing crop residues have severely disturbed and destroyed the natural structure of the soil, resulting to a continuous decline in the soil organic matter content, which restricts the increase of crop grain yield [1]. After straw application for six consecutive years, the soil organic carbon and available nitrogen contents in each soil aggregate-size class increased by 27% and 12%, respectively [2], compared with those of Scientific Programming soils without crop residues. A previous study has demonstrated that the plowing tillage technology during straw application can increase the organic carbon and total nitrogen contents of the surface soil layers, thereby increasing the maize grain yield and water use efficiency [23]. In rain-fed arid areas, straw mulching with minimum tillage can significantly increase the organic carbon content [22], moisture content, and permeability [29] of the 0–100 cm soil layer, thereby increasing the crop grain yield and soil quality. We investigated the influences of the straw application in combination with different soil tillage methods on soil tilth and maize grain yield and determined the most appropriate straw application method under mechanical grain harvesting. e findings from this study provide a theoretical basis and technical approach for improving the soil quality and increasing the maize grain yield
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
