‘正午’牡丹微繁殖体系的建立

本研究以‘正午’牡丹腋芽为外植体,建立了高效的牡丹微繁殖体系。腋芽的初始培养基为WPM+0.5mg/L BA+0.2mg/L GA3,培养50d后,一个丛生芽平均可切分为13个繁殖体用于增殖培养;增殖培养基为WPM[1668mg/L Ca(NO3)2·4H2O]+0.5mg/L BA+0.2mg/L GA3,以35d为一个继代培养周期,增殖率为3.0,共继代培养7次;生根培养时,先将无根苗在复壮培养基[1/2MS(296mg/L CaCl2)+0.5g/L活性炭]上培养20d,再转入根诱导培养基[1/2 MS(296 mg/L CaCl2)+1.0 mg/L腐胺+1.0 mg/L IBA]培养30d,最后转入根形成培养基[1/2 MS(296mg/L CaCl2)+4.0g/L活性炭]培养20d,其生根率达77.2%;驯化与移栽基质为珍珠岩∶蛭石∶草炭土=1∶1∶1,组培苗移栽成活率高达92.1%。这表明以‘正午’牡丹腋芽建立的微繁殖体系具备规模化商业生产的价值。

Protocol for the Micropropagation of Tree Peony (Paeonia × lemoinei ‘High Noon’)

An efficient micropropagation protocol was developed for Paeonia × lemoinei ‘High Noon’ using axillary buds as explants. During initiation, 13 propagules were obtained after 50 d of culture with WPM + 0.5 mg/L BA + 0.2 mg/L GA₃. During proliferation, three shoots were obtained after 35 d of culture with WPM[1668 mg/L Ca(NO₃)₂·4 H₂O] + 0.5 mg/L BA + 0.2 mg/L GA₃, and seven subcultures were carried out. For optimal rooting, the shoots were cultured with 1/2 MS (296 mg/L CaCl₂) + 0.5 g/L activated charcoal for 20 d, then 1/2 MS (296 mg/L CaCl₂) + 1.0 mg/L putrescine + 1.0 mg/L IBA for 30 d for root induction, and finally 1/2 MS (296 mg/L CaCl₂) ＋ 4.0 g/L activated charcoal for 20 d for root development. The rooting percentage of the shoots was 77.2%. During acclimatization, the rooted plantlets were transferred to pots containing a mix of vermiculite/peat/perlite (1:1:1 V/V/V) substrate, and the survival rate was 92.1%. The micropropagation protocol for Paeonia × lemoinei ‘High Noon’ established in this study is valuable for commercial use.