Origin, evolution, and Chinese translation issues of the“Spindle”training system in fruit trees

The“spindle”is a fundamental training system in modern high-density orchards; however, its traditional Chinese translation as“纺锤形”(fusiform/spindle-shaped) has long caused morphological cognitive bias and practical misunderstandings. This paper systematically reviews the origin and evolution of the spindle system, from the initial spindle bush to the widely adopted slender spindle and tall spindle. It highlights that the core technical logic throughout its evolution has consistently been the reinforcement of the absolute dominance of the vertical central leader while progressively eliminating large lateral branches. Through etymological comparison, the study reveals that the English term“spindle”, acting as a concrete noun, emphasizes a long, straight axis or spinning rod that provides structural support and central bearing. In contrast, the Chinese translation corresponds geometrically to“fusiform”—a shape characterized by a swollen middle and tapered ends. This geometric outline contradicts the actual conical or approximately cylindrical appearance of modern spindle architectures and results in a detrimental practice in canopy light management. Academic tracing indicates that the Chinese term was originally borrowed from early Japanese Kanji translations, a practice that modern Japanese scholars are increasingly abandoning in favor of phonetic transcriptions to avoid ambiguity. Consequently, this paper officially proposes renaming the spindle training system in Chinese to“主轴形”(semantically equivalent to central axis shape). This proposed translation accurately conveys the system’s structural essence of a“strong central leader, weak lateral branches, and uniaxial extension”. Rectifying this terminology will eliminate long- standing conceptual confusion and provide more precise guidance for both theoretical research and practical canopy management in pomology