以绣球花筑紫之风 ( Hydrangea macrophylla ‘Chikushi-no-kaze’) 无菌苗叶片为外植体, 探究不同叶位、暗培养时间及植物生长调节剂等对愈伤组织诱导、不定芽再生和增殖、壮苗生长及生根的影响。结果表明, 筑紫之风组培苗第3–5位叶 (中部成熟叶片) 为最佳取样叶位, 暗培养10–14天有利于愈伤组织诱导和不定芽再生, 最适培养基为MS+3.0 mg·L^–1 CPPU+0.1 mg·L^–1 2,4-D, 诱导率和再生率分别为97.78%和93.33%; 不定芽增殖最适培养基为MS+2.0 mg·L^–1 6-BA+0.1 mg·L^–1 IBA, 增殖系数达8.33; 壮苗生长最适培养基为MS+1.0 mg·L^–1 6-BA+0.1 mg·L^–1 IBA, 幼苗平均茎高为4.10 cm; 采用MS+0.3 mg·L^–1 IBA培养基进行生根培养, 生根率可达87.20%。该研究建立了绣球花筑紫之风离体再生技术体系, 为种苗快繁、品种改良和基因功能研究提供了技术支撑。

INTRODUCTION: Hydrangea macrophylla is essential in landscaping, ecology, and medical care, with significant development prospects. Chikushi-no-kaze is an ideal low-maintenance variety for microlandscaping and potted H. macrophylla, which are widely favored by consumers. However, the extremely low setting rate of H. macrophylla and poor seed development under natural conditions render traditional reproduction methods inadequate for meeting the demands of large-scale annual production in the market. The breeding of H. macrophylla plantlets through tissue culture technology is currently the most efficient method for producing high-quality plantlets. RATIONALE: Regeneration efficiency in plant tissue culture is a key factor in achieving factory seedling production. Therefore, this study investigated the regeneration efficiency of isolated leaves from tissue culture plantlets of Chikushi-no-kaze under optimal culture conditions at each key stage, considering different leaf positions, dark culture durations, and other factors. The aim was to establish an efficient regeneration technology system that provides technical guidance for large-scale plantlet production and serves as a reference for establishing a genetic transformation system for H. macrophylla in the future. RESULTS: The 3^rd to 5^th leaves (middle mature leaves) of Chikushi-no-kaze tissue culture plantlets were identified as the optimal sampling leaves. A dark culture duration of 10–14 days was conducive to callus formation. The most suitable medium for the induction and regeneration of adventitious buds was MS+3.0 mg·L^–1 CPPU+0.1 mg·L^–1 2,4-D, with induction and regeneration rates of 97.78% and 93.33%, respectively. The optimal medium for adventitious bud proliferation was MS+2.0 mg·L^–1 6-BA+0.1 mg·L^–1 IBA, yielding a proliferation coefficient of 8.33. For elongation growth, the optimal medium was MS+1.0 mg·L^–1 6-BA+0.1 mg·L^–1 IBA, resulting in an average stem length of 4.10 cm. The optimal medium for rooting culture was MS+0.3 mg·L^–1 IBA, achieving a rooting rate of 87.20%. CONCLUSION: This study initially established a technical system for in vitro leaf regeneration of the large leaf H. macrophylla ‘Chikushi-no-kaze’, which effectively solved the problem of low efficiency of adventitious bud regeneration of H. macrophylla and helped to achieve efficient reproduction and recycling. This study lays the foundation for the large-scale production and genetic improvement of H. macrophylla.