Interactions between sweetpotato Pushu 32 and soil factors shape starch accumulation, starch pasting, texture of starch and cooked storage roots, and cooked storage roots' sensory quality

Pushu 32 (P32) is an elite fresh-eating sweetpotato cultivar with prominent quality variation under diverse ecological soils. To clarify the multi-scale drivers of its quality across production areas, storage roots from 12 representative planting locations were collected. Measurements included starch and amylose contents, starch pasting properties, texture properties of starch and cooked storage roots, cooked storage roots' eating sensory quality, and relative expression levels of core starch biosynthetic genes. Significant site-specific differences were observed in all the above measured traits of P32. Temperature-dependent texture-sensory coupling relationships were observed in cooked P32: mastication-related chewiness regulated sweetness perception, and starch retrogradation-induced springiness shaped sensory viscosity. Differential expression of key starch biosynthesis genes modulated starch biosynthesis efficiency and amylose accumulation. This study systematically reveals a multi-level framework of “soil environment driver-starch biosynthetic gene regulation-functional properties-origin clustering”, where origin clustering means grouping samples by their geographical planting origins according to their principal component analysis.