Abstract:

In order to explore the reproductive characteristics of Metasequoia glyptostroboides, we explored a native population of original Metasequoia glyptostroboides. We investigated the core germplasm of 40 individuals of native Metasequoia glyptostroboides and collected data on habitats, parent trees and seed traits. We used field experiment to analyze reproductive characteristics. We detected differences in seed traits, germination rate and seedling growth characteristics among different parent trees using ANOVA. The effects of individual traits on seeds, germination rate and seedling growth were analyzed with correlation and linear regression models. The results showed that: (1) There were only 7 strains from 40 mother trees, the seed yield rate was 17.50%, and the difference in seed yield of 7 original mother trees was significant (P < 0.05). (2) There were significant differences in seed weight (1,000 grain), seed germination rate, seedling survival rate and base diameter growth among individuals of different parent trees (P < 0.05). (3) The average germination rate of seeds from seven mother trees was 19.73%, and the average survival rate of seedlings was 73.42% (inter-individual rates were also significantly different (P < 0.05). (4) Diameter at breast height (DBH) was negatively correlated with seed weight and germination rate (P < 0.05), while seed germination and seed weight (P < 0.05), seed germination and seedling survival (P < 0.001), and tree height and seedling survival (P < 0.05) were positively correlated. (5) The height of mother tree was positively correlated to seedling survival rate (P < 0.05), and DBH was negatively correlated to seed germination rate (P < 0.05); and (6) Seedling growth (height and base diameter) conforms with logistic growth (R ² ≥ 0.928).

Key words: Metasequoia glyptostroboides, original population, core germplasm, Logistic growth