Abstract:

Given the severe degradation of black soil in the semi-arid region of the western Songnen Plain and the inability to sow on time in some areas during spring, in order to clarify the mechanism of soil correlation during spring sowing and the growth and development of maize, clarify the adaptability rules for timely sowing of crops under different soil characteristics, strengthen the exploration and application of soil freeze-thaw cycles in the black soil area of Northeast China, and provide practical and effective theoretical basis and practical reference for timely spring sowing of crops in this climate zone. This experiment was based on the long-term positioning monitoring of soil quality at the Keshan Branch of Heilongjiang Academy of Agricultural Sciences. Under the conditions of freeze-thaw alternation in the medium thick black soil ecological zone, different terrain and landform soil water and heat conditions were monitored during the spring sowing period, and crop sowing adaptability evaluation was studied. Field experiments were conducted with different spring sowing period treatments: SD1 (April 15), SD2 (April 20), SD3 (April 25), SD4 (April 30), SD5 (May 5), and SD6(May 10) to monitor soil water and heat characteristics and analyze the growth, development, and yield formation of spring maize under different spring sowing treatments.As the spring sowing period was postponed,the external temperature gradually increased,accompanied by rainfall.The air humidity and soil temperature and humidity in the plow layer gradually increased,the soil bulk density decreased,the proportion of water stable aggregates decreased,and the proportion of small particle size soil particles showed an upward trend.Under different soil water and thermal conditions, the plant height, basal internode stem diameter, and root length of maize treated with the sowing date of SD5 during the tassel emergence stage to grain filling stage were significantly superior to those treated with other sowing dates; meanwhile, the SPAD value and leaf nitrogen content of maize leaves at different growth stages also showed better performance.In terms of maize ear traits and yield performance,SD4 treatment showed better performance in ear row number,ear shaft thickness,and seed depth;at the same time,the maximum yield was 13 545.23 kg/ha,which was significantly increased by 12.58% to 56.21% compared to the other treatments.Based on the actual ecological and climatic conditions of farmland in the middle thick black soil area in the northwest of the Songnen Plain,as well as the background of soil water and heat characteristics,timely early sowing of spring corn could make reasonable use of external light and water resources,promote plant growth and development,optimize plant dry matter accumulation,and achieve early and rapid harvest,thus achieving high and stable yield.

Key words: Medium thick black soil area, Farmland soil, Hydrothermal effect, Spring corn, Timely spring sowing

CLC Number: 

• S513玉米(玉蜀黍)

• Q945.79