关键词: 紫薇（Lagerstroemia indica L.）, 修剪强度, 留芽数量, 花期调控

Abstract: ： The five-year potted seedlings of Japanese multicolored （Lagerstroemia indica） were used as test materials. The effects of pruning intensity and the number of remaining buds on the secondary flowering of L. indica were studied using a two-factor completely randomized block design. The results showed that pruning intensity had a significant effect on sprout length, and the germination of light and medium-sized cutting shoots was better. The pruning intensity and the number of remaining buds and their combinations have extremely significant effects on the flower branch length, inflorescence length, and the number of inflorescences of the L. indica after pruning. The index of inflorescence length, number of small flower branches, and inflorescence number of the whole plant were slightly higher with slight cutting and moderate cutting with 4 buds respectively. Pruning intensity has a greater effect on the main phenological stages such as the initial flowering stage, the flowering stage, and the last flowering stage after prunes. L. indica can be re-flowered by trimming, and the flowering period can be prolonged by 55 d. Different pruning intensities and the number of remaining buds can effectively affect the condition of flowering again of L. indica.

Key words: Lagerstroemia indica, pruning intensity, remaining buds number, flowering regulation