Abstract:

The paper aims to evaluate the ornamental value of Acer leaf color in autumn, the Acer pseudo-sieboldianum, A. triflorum and A. mandshuricum leaves were chose as the experimental materials to observe and analyze the leaf morphological characteristics, leaf color temporal changes and leaf color parameters during the discoloration period. The results showed that there were significant differences in leaf morphological characteristics (leaf length, leaf width, leaf length/ width, leaf circumference and leaf area) among the three Acer species. The leaf morphology of A. mandshuricum and A. triflorum was similar. The leaf area of A. triflorum was the largest, and that of A. pseudo-sieboldianum was the smallest. The leaf circumference from large to small was: A. mandshuricum> A. pseudo-sieboldianum> A. triflorum. The ornamental period of the three Acer species was from the end of September to the end of October, and A. triflorum had the longest ornamental period. A. mandshuricum had the richest changes in leaf color in autumn and the most ornamental. The leaf color parameters L^* and b^* both showed a trend of increasing first and then decreasing, while the leaf color parameter a^* showed a trend of increasing gradually, which was consistent with the change of leaf color.

Key words: Acer, discoloration period, morphological characteristics, temporal variation, leaf color parameter