Abstract:Parrotia subaequalis (H. T. Chang) R. M. Hao & H. T. Wei is a species under first-class national state protection and an endemic relict plant of the Hamamelidaceae family in China. Taking the provincial forestry and grassland germplasm resource bank of P. subaequalis in Changchun Village, Changling Township, Jinzhai County, Anhui Province as the research object, this study conducted a systematic background survey of 1,964 wild P. subaequalis individuals within the bank using a combination of comprehensive field surveys and quadrat sampling. Simultaneously, precise measurements and analysis of variance (ANOVA) were performed on the seed phenotypic traits from 22 germplasm sources. The main results are as follows: (1) Regarding population structure, the P. subaequalis population within the germplasm bank exhibited an expanding trend with an "upright pyramid" age structure. There were 1,152 seedlings with a diameter at breast height (DBH) or basal diameter < 5 cm, accounting for 58.66% of the total individuals. A total of 1,815 individuals ranged from seedlings to medium-diameter trees (< 20 cm), comprising 92.41% of the total, indicating a strong momentum for population regeneration. (2) In terms of sprouting regeneration, among the 83 large individuals with a DBH or basal diameter ≥ 30 cm, sprouting-type individuals with bifurcated stem bases accounted for a high proportion of 74.7% (62 individuals). The largest individual possessed 9 basal branches and a basal diameter of 165 cm, suggesting that sprouting regeneration acts as the primary compensatory mechanism for this population following historical anthropogenic disturbances. (3) Regarding seed phenotypes, the thousand-seed weight across the 22 germplasm sources was 30.768 ± 1.837 g, ranging from 27.41 to 33.39 g, with a coefficient of variation (CV) of 6%. The seed length, width, and length-to-width ratio were 6.418 ± 0.226 mm, 3.070 ± 0.082 mm, and 2.091 ± 0.066, respectively. A highly significant positive correlation was observed between seed area and thousand-seed weight (R² = 0.6749, p < 0.001). This study reveals the atypical structural characteristics of the P. subaequalis population in Jinzhai, characterized by "abundant seedlings, scarce medium-diameter individuals, and sprouting dominance," providing fundamental data support for the precise conservation and germplasm resource development of this species.