In the golden autumn season, corn stands plump and firm, rice fields ripple with golden waves, and sorghum reddens across the fields. Various grain and oil crops are successively entering the harvest period, painting a picture of abundant harvest across the land.
During this autumn harvest season, the achievements in high-yield cultivation of grain and oil crops are particularly remarkable, with multiple yield per unit area data reaching new highs—
In the core demonstration area for comprehensive yield improvement, corn yield per mu reached 798.5 kilograms, setting a new record for corn yield in the region;
In the rice yield improvement demonstration areas, average rice yields reached 842.44 kilograms and 830.9 kilograms per mu respectively, both breaking through 800 kilograms in large-scale production;
In various locations, soybean yields in pure stands consistently exceeded 200 kilograms per mu, with the highest reaching 275 kilograms, representing a significant improvement compared to the current regional average of 150 kilograms…
Recent investigations have revealed that behind these encouraging achievements lies a crucial “yield-increasing code”—increased planting density.
Increased Density Means Increased Yield
In recent years, the grain sowing area has remained stable at over 30 million mu, with grain production generally maintaining stability and yield per unit area gradually increasing. However, there remains a considerable gap compared to the national average level. Particularly as the potential for expanding cultivated land continues to diminish and the pathway to ensuring grain security through “area expansion” becomes increasingly limited, improving grain yield per unit area through technological means has become a key approach to ensuring food security. For this reason, continuous efforts have been made to enhance yields of major grain and oil crops on a large scale.
Agricultural experts explain that to achieve yield increases within limited areas, two factors are crucial: varieties and technology. “On one hand, we achieve yield increases through the promotion of high-yield varieties. On the other hand, we promote deep compatibility between varieties and density-increasing technologies. Through reasonable dense planting, we increase the number of effective plants per unit area, thereby directly driving yield improvement.”
In fact, in recent years, influenced by factors such as labor shortages, “sparse planting” has been a common phenomenon in grain and oil production. “When planting rice, only about 8,000 clusters are planted per mu, which is indeed quite sparse,” admits a farmer from Xianlin Village. “Farming mainly relies on me and my spouse. With insufficient manpower, we can only try to ‘save effort’ when transplanting seedlings, so density naturally doesn’t increase.”
“Actually, the planting density for rice can reach 12,000 clusters per mu, which can immediately increase yield by about 30%,” emphasizes agricultural specialists. “Therefore, for grain and oil production, increased density means tangible yield increases.”
Challenges in Increasing Density
However, in actual production, increasing density faces multiple challenges.
The foremost challenge is technical compatibility. In the industrial park, when agricultural experts suggested increasing rice transplanting density to 15,000 clusters per mu, the initial reaction from local large-scale rice grower Xu Feng was skepticism.
“This is simply unbelievable. We previously planted 8,000 clusters per mu. With such density, light permeability becomes worse, which will definitely worsen disease occurrence,” Xu Feng’s concern was direct: density increase is possible, but pest and disease control issues must be solved first.
The shortage of density-tolerant varieties is another major constraint. Taking sorghum as an example, as the core brewing raw material for premium liquors in southwestern China, the region has a long history of glutinous sorghum cultivation and is also an important production area for glutinous sorghum nationwide.
However, due to limited germplasm resources of glutinous sorghum, existing specialized varieties for the liquor industry have been improved and selected from limited domestic germplasm resources, and all are tall varieties, with plant heights ranging from 2.6 to 3.5 meters.
“When existing varieties are densely planted, plants compete for height to absorb sunlight, which反而 affects nutrient transport to the panicles, impacting sorghum yield. Plus, their naturally tall stature makes them more prone to lodging under dense planting, making mechanical harvesting difficult,” explains crop experts.
Traditional beliefs among growers are “invisible barriers” to promoting density-increasing technologies.
“Soybeans should be planted this way; higher density will only lead to excessive vegetative growth without pod setting. I’ve grown soybeans for so many years and never seen dense planting achieve high yields,” says large-scale soybean grower Chen Liujiang from Kaizhu Village. In his固有认知, soybeans are “reliable
