“凤丹”牡丹花丝愈伤组织诱导及分化研究

Callus Induction and Differentiation from the Filaments of Paeonia ostii‘Feng Dan’

以“凤丹”花丝为外植体,探究了外植体发育时期、基本培养基和植物生长调节剂(plant growth regulators,PGRs)对愈伤组织诱导、增殖和分化的影响,并对不同类型的愈伤组织进行了形态组织学观察。结果表明:花蕾直径为13~19mm时、半透明或白色的幼嫩花丝更适宜愈伤组织的诱导;愈伤组织诱导的最适培养基为SH添加2,4-D 1 mg·L-1、NAA 2 mg·L-1及BA 0.2 mg·L-1,最高诱导率和诱导量分别为99.12%和5.68 g;愈伤组织增殖的最适培养基为SH添加2,4-D 0.5 mg·L-1、NAA 0.5 mg·L-1及BA 0.25 mg·L-1,增殖率为3.86;花丝愈伤组织根据形态结构可分为三类,Ⅰ类愈伤组织具有典型的胚性愈伤组织特征,可进一步分化产生体胚;Ⅱ类愈伤组织和Ⅲ类愈伤组织内部呈现大量维管组织分化,其中Ⅱ类愈伤组织中观察到了不定芽的分化,Ⅲ类愈伤组织未见分化。上述结果表明“凤丹”花丝具有重要再生潜力,是一种良好的新型外植体,对研究建立牡丹体外再生体系具有重要价值。

With the filaments of Paeonia ostii as explants,the effect of developmental stage of explant,basal media and PGRs on callus induction,proliferation and differentiation were investigated,and the morph-histological observation of different types of callus was performed.The translucent and white filaments from flower bud of 13-19 mm in diameter is optimal for callus induction.The optimal callus induction medium was SH containing 1 mg·L-12,4-D,2 mg·L-1 NAA and 0.2 mg·L-1 BA.The optimal proliferation medium was SH containing 0.5 mg·L-12,4-D,0.5 mg·L-1 NAA and 0.25 mg·L-1 BA,and the proliferation rate was 3.86.The filaments callus can be divided into three types according to their morphological and microstructural characteristic,the typeⅠcallus presented typical embryogenic callus characteristics,and somatic embryogenesis was observed from this kind of callus;there were plenty of vascular tissues formed in the typeⅡand typeⅢcallus,and shoot organogenesis was observed from the typeⅡcallus,but no morphogenesis from the typeⅢcallus.These results suggested that the filaments have important regeneration potential as a good novel explant source,which have important value in establishing in vitro regeneration system of tree peony.