Multi-trait evaluation identifies superior Dendrocalamus latiflorus germplasm for sustainable bamboo plantation development.

Dendrocalamus latiflorus is an economically important bamboo species, but the physiological and molecular mechanisms underlying provenance-dependent growth variation remain poorly understood. This study aimed to identify superior germplasm and elucidate the mechanisms associated with high productivity. Eighteen D. latiflorus provenances were evaluated under common-garden conditions over two consecutive growing seasons using growth, morphological, photosynthetic, nutrient, biochemical, multivariate, and transcriptomic analyses. Significant provenance variation was observed in the first evaluation year diameter at breast height ranged from 19.25 to 48.47 mm and plant height from 1.82 to 5.19 m. Lianjiang showed the highest net photosynthetic rate (12.16 μmol CO2 m-2 s-1), whereas Yong'an had the greatest stem diameter (48.47 mm) and organic carbon content (42.27 mg g-1 DW). Principal component analysis explained 48.11% of the total variation, and the integrated selection index identified Lianjiang, Fuqing, and Yong'an as superior germplasm resources. Comparative transcriptomic analysis revealed differential regulation of photosynthetic carbon fixation, glycolysis/gluconeogenesis, the pentose phosphate pathway, and carbon metabolism, indicating provenance-specific regulation of carbon assimilation and energy metabolism. These findings provide a physiological and molecular basis for selecting high-productivity D. latiflorus germplasm and support sustainable bamboo plantation development.