Experts from the Beijing Plant Protection Station, the Beijing Agricultural Technology Extension Station, and the Huairou District Agriculture and Rural Affairs Bureau formed a yield measurement panel to conduct an actual harvest yield assessment on a 1,600-mu high-yield spring corn demonstration field in Baoshan Town, Huairou District, Beijing. Following the national procedures for grain high-yield creation yield measurement and acceptance, the panel carried out on-site sampling, weighing, and grain moisture testing. After converting to 14% standard moisture, the demonstration field's average corn yield reached 1,017.14 kilograms per mu, marking a ton-level breakthrough in large-scale spring corn yield per unit area in the mountainous valley areas of Beijing's suburbs.

Baoshan Town in Huairou District is located in the mountainous area of northern Beijing, with the project zone at an altitude of 400 to 800 meters. It has a cool climate with large temperature differences between day and night, making it suitable for growing corn and other grain crops. The area has shallow soil layers, high gravel content, and weak soil water and fertilizer retention capacity. The conventional corn yield in the area is only 500 to 600 kilograms per mu. The demonstration field's yield exceeding 1,000 kilograms per mu represents a near doubling of productivity, demonstrating the remarkable effect of technological measures on improving the productivity of barren valley farmland.

"Behind the ton-level yield is a complete set of technical solutions fully adapted to the production conditions of mountainous valley areas," said Dr. Cai Wantao, chief expert of the project and a researcher at the Corn Research Institute of the Beijing Academy of Agriculture and Forestry Sciences.

The demonstration field, centered on the integration of improved varieties with improved methods and the deep fusion of agricultural machinery and agronomy, has established a replicable and promotable "Baoshan model" for increasing corn yield per unit area in Beijing's mountainous suburbs. In response to the complex terrain of a 63-kilometer-long narrow valley with significant altitude differences, a differentiated variety layout model for valley terrain was implemented. New nationally approved corn varieties with stress resistance and high yield, including Xiandai 959, NK815, Longyun 976, Jingke 566, MC812, and MC703, were selected and precisely matched with suitable planting densities according to altitude gradients and soil fertility differences between terraced fields and flat land. Navigation-based precision seeding and scientific and rational dense planting techniques were integrated to fully tap the yield potential of corn populations. Shallow-buried drip irrigation and water-fertilizer integration technology were applied on a large scale. Targeting the prominent issue of soil fertilizer and water leakage in the area, differentiated "small amounts, multiple applications" water and fertilizer regulation was implemented to solve the problem of fertilizer deficiency and premature aging in the mid-to-late growth stages, significantly improving water and fertilizer use efficiency. Multidisciplinary experts provided on-site services throughout the entire cycle, from sowing and seedling management to disaster response and harvesting.

This integrated technical system provides a mature, replicable, and promotable practical model for tapping grain production potential in similar valley and mountainous farmland in Beijing and northern China. It is reported that next, the research team will continue to optimize and improve technical regulations, expand the scale of demonstration and promotion, and promote the transformation of research achievements into stable and increased field production capacity, supporting the high-quality development of the grain industry in Beijing's suburbs and providing technical support for grain yield increases in mountainous valley areas of northern China.