Physiological basis and practical strategies for enhancing rapeseed yield under direct seeding

Enhancing the self-sufficiency rate of edible vegetable oil and ensuring the security of oil supply represent a critical challenge for oilseed production in China. Rapeseed is a vital source of both edible oil and feed protein. Since 2000, China’s rapeseed production system has progressively transitioned from seedling transplantation to a modernized model centered on direct-seeding cultivation. Within this systematic technological evolution, a foundational framework for direct-seeding rapeseed production has been largely established. The adoption of rational close planting has not only effectively reduced production costs and enhanced efficiency but has also provided key technological support for safeguarding domestic edible oil supply and promoting sustainable agricultural development. However, this new model still faces a series of scientific and technical problems requiring urgent resolution. A core research question, particularly under high-density planting conditions, is how to synergistically increase yield per unit area and resource use efficiency. Research focus is gradually shifting from constructing macro-level cultivation systems to a deeper analysis of the key agronomic factor-“close planting”-aiming to elucidate the underlying theoretical mechanisms and practical constraints for yield and efficiency gains, thereby guiding future technological breakthroughs. This paper summarizes the development status of direct-seeding rapeseed in China and proposes a developmental stages framework (Stage 1.0 to 4.0). It analyzes the limiting factors for achieving high yield and efficiency under close planting, which manifest as non-synergistic yield components, weak individual plant growth, and severe lodging. Drawing insights from ideal plant architecture research in cereal crops, the paper discusses traditional and smart ideal plant architecture traits for lodging-tolerant and high-yielding direct-seeding rapeseed, along with their physiological basis, focusing on efficient biomass accumulation and partitioning, improvement of stem strength and lodging resistance, and root-shoot synergy to enhance density tolerance. Pathways for yield improvement and future research directions are further clarified. With ongoing advances in functional gene discovery and technology commercialization, the rapeseed production system is poised to evolve further towards high yield, high efficiency, and intelligentization.