Genetic variation and comprehensive evaluation of different provenances of Dendrocalamus latiflorus at seedling stage

To reveal the genetic basis of important economic traits in Dendrocalamus latiflorus, elucidate the patterns of genetic variation, and to accelerate the process of genetic improvement and precision breeding.

Eight geographically diverse D. latiflorus provenances were evaluated, with provenance codes LZ-1, LZ-2, LZ-3, LZ-4, BS, YD, JY, and FJ. Seedling stage phenotypic variation was analyzed by assessing above- and below-ground morphological traits and biomass. Genetic parameters were estimated. Superior provenances were identified using membership function for comprehensive evaluation.

11 phenotypic traits showed significant (P<0.05) or extremely significant (P<0.01) differences among different provenances of Ma bamboo (Dendrocalamus latiflorus). Among them, provenance YD had the highest number of shoots (8.83); provenance LZ-4 had the highest values for leaf expansion number, average root length, leaf area, ground diameter, and plant height (25.63, 9.76 cm, 9 566.77 mm², 19.70 mm, 2.96 cm, respectively); provenance LZ-3 had the highest number of roots, average root diameter, root biomass, and culm number (23.19, 1.22 mm, 1.20 g, 1.64, respectively); provenance FJ had the largest culm biomass (82.93±24.46 g). The genetic coefficient of variation for each trait ranged from 0.34% to 36.92%, and heritability (H²) exceeded 0.50 for all traits; heritability was extremely high for plant height (0.96), culm number (0.95), leaf area (0.94), ground diameter (0.92), and number of shoots (0.89). Correlation analysis showed that the number of bud emergence was significantly (P<0.05) or extremely significantly (P<0.01) positively correlated with leaf expansion number, mean root length, mean root diameter, bud biomass, and leaf biomass. Leaf area was extremely significantly (P<0.01) positively correlated with bud biomass, leaf biomass, root biomass, total biomass, and culm number. Regarding phenotypic genetic gain for each trait, provenance LZ-4 was the most prominent, with positive genetic gains for multiple traits, including number of shoots (2.53%), leaf expansion number (7.03%), average root length (1.84%), bud biomass (2.56%), leaf biomass (1.24%), and ground diameter (2.23%). Based on principal component analysis, four principal components were extracted, with a cumulative contribution rate of 79.034%, covering key phenotypic characteristics such as growth activity, root development, and biomass accumulation of Ma bamboo. The comprehensive evaluation results showed that provenance LZ-4 had the highest comprehensive score (1.179).

The eight provenances of Ma bamboo showed differences in seedling traits, among which provenance LZ-4 performed best, followed by JY, BS and LZ-2.