五寸石竹毛状根诱导及其植株再生

建立了五寸石竹(Dianthus chinensis)毛状根诱导及其植株再生体系。用含野生农杆碱型Ri质粒的发根农杆菌(Agrobacterium rhizogenes)15834感染五寸石竹叶片外植体10天后,从其形态学下端产生白色不定根;30天后,叶片外植体的生根率为95%;所产生的毛状根能在无外源生长调节剂的固体和液体MS培养基上快速自主生长。遗传转化鉴定结果表明,发根农杆菌Ri质粒的生根基因(rol)已在毛状根基因组中整合并表达。五寸石竹毛状根的根段在成分为MS+2.0 mg·L~(–1)6-BA+0.2 mg·L~(–1) NAA的培养基中培养15天后产生浅绿色疏松愈伤组织;将愈伤组织转入成分为MS+1.0 mg·L~(–1) 6-BA+0.02 mg·L~(–1) NAA的培养基中培养30天后逐渐形成不定芽。盆栽的五寸石竹毛状根再生植株与非转化植株(对照)相比节间缩短,开花期提前18天。

Induction of Hairy Roots of Dianthus chinensis and Its Plant Regeneration

This study established an efficient system for inducing hairy roots and plant regeneration of Dianthus chinensis. Hairy roots could be induced from the basal surface of leaf explants of D. chinensis at 10 days after inoculation with the strain of Agrobacterium rhizogenes ATCC15834 harbouring the wild agropine-type plasmid. The percentage of rooting leaf explants was 95% at 30 days after inoculation. Hairy roots could grow rapidly and autonomously in liquid or solid plant-growth regulator-free MS medium. The transformation was confirmed by PCR amplification of the rol gene of the Ri plasmid from D. chinensis hairy roots. Hairy roots could form light green callus after culture on MS + 2.0 mg·L^-1 6-BA + 0.2 mg·L^-1 NAA for 15 days. Adventitious shoots were gradually produced from calli after culture on MS + 1.0 mg·L^-1 6-BA + 0.02 mg·L^-1 NAA for 30 days. Compared to the control, pot-grown plants regenerated from hairy roots had shorter internodes and flowering was earlier by 18 days.