[Smart Farmers] Uncovering the scientific secrets of corn harvest: "Dense Planting, High Yield and Precision Control Technology"

Corn is an important food, feed and industrial raw material crop in the world, and is of great significance to ensuring world food security. The planting area and total output of corn rank first among my country's food crops, and there is still great potential for increasing the yield per unit area of ​​corn.

Recently, "Biotechnology Bulletin" published an article signed by Zhao Jiuran and Yan Jianbing, which mentioned that varieties are the basis of high corn yields, and further improving variety density tolerance and planting density is the key to increasing corn yield per unit area.

Why dense planting?

Relevant statistics show that in the past 80 years, the corn yield per unit area in the United States has increased nearly 8 times. During this process, the planting density has increased from an average of more than 2,000 plants per acre to nearly 6,000 plants per acre. There is a significant growth relationship between planting density and yield.

During the updating and iteration of new high-yield corn varieties in my country, the corn plant type has gradually evolved from flat to compact, and the variety's density tolerance has been significantly improved. However, the planting density is at the level of 3,500-4,000 plants per mu. Compared with the planting density in the United States, there is still great potential.

Why does close planting increase yield?

The increase in yield from dense planting is due to the higher photosynthetic production capacity of the group. Compact corn varieties have improved the angle of leaves above the ear position, the size of the tassel and other traits, thereby improving the canopy structure and canopy light radiation distribution of the corn group, enhancing the ventilation and light transmission of the group, and the effective leaf area index, significantly improving the photosynthetic efficiency and yield of the corn group. Cultivating varieties with compact plant types and high density tolerance is of great significance to the increase in corn dense planting yield and the realization of sustainable agricultural development.

However, when corn is planted densely, competition for limited light, temperature, water and fertilizer intensifies, causing the plants to increase in height and weaken the stalks, making them more susceptible to prominent problems such as lodging, hollow stalks, small spikes and weakened resistance to stress.

"Corn dense planting high-yield precise control technology" promotes the effective improvement of planting density

The high-yield precision control technology for dense corn planting developed by the Chinese Academy of Agricultural Sciences takes dense planting as the core of increasing production, and uses drip irrigation and integrated water and fertilizer facilities to supply water and fertilizer on demand, in stages, and in a targeted manner throughout the growth process of corn, providing a material basis for effectively increasing the density of corn planting. The system integrates the "six major precision" control key technologies of land fine tillage technology, seed precision coating technology, navigation single-grain precision sowing technology, water and fertilizer integration technology, precision chemical control and pest and disease prevention and control technology, and mechanical precision harvesting technology, and adopts comprehensive measures to solve the prominent problems of dense corn planting, such as "lodging, empty stalks, premature aging, and weakened resistance", and continuously refreshes regional high-yield records and large-scale production yield records in major production areas such as Northwest, Northeast, Huanghuaihai, etc. in my country. It has opened up a technical approach with Chinese characteristics for improving my country's corn production capacity and achieving high-yield and high-efficiency corn.

Song Yajuan compiled from Biotechnology Bulletin, Xinhua News Agency

Review expert: Ming Bo, associate researcher at the Institute of Crop Science, Chinese Academy of Agricultural Sciences