南美蟛蜞菊毛状根诱导及其离体培养

为了探讨利用南美蟛蜞菊毛状根来改良其观赏性状和生产次生物质,研究了南美蟛蜞菊Wedelia trilobata(L.)A.S.Hitche毛状根的诱导及其离体培养过程中培养基N源、碳源、磷和钙的消耗变化。结果表明,发根农杆菌Agrobacterium rhizogenes ATCC15834感染南美蟛蜞菊幼嫩叶片外植体7d后从其叶片切口中脉处产生毛状根。毛状根能在无外源激素的培养基上自主生长。PCR扩增结果显示发根农杆菌Ri质粒的rol B和rol C基因已在南美蟛蜞菊毛状根基因组中插入、整合并得到表达。毛状根液体培养0~7d内处于生长迟滞期、7~21d为快速生长期、21d后进入生长平台期。在毛状根液体培养过程中培养基的蔗糖、硝态氮、PO43?、Ca2+被逐渐吸收和消耗,培养至7d时,蔗糖被消耗近50%;硝态氮含量只剩下起始硝态氮含量的5.8%;至35d时,蔗糖和硝态氮含量分别约为其起始浓度的3.39%和1.82%。与Ca2+浓度变化不同的是,培养基的无机磷被快速消耗,培养至7d时其浓度约为其起始浓度的1.76%;但培养至35d时培养基中仍残存有占起始浓度约61.3%的Ca2+。该结果为今后利用南美蟛蜞菊毛状根来改良其观赏性状和设计合适的培养基来规模培养生产其次生物质提供了可能性。

Induction and in vitro culture of Wedelia trilobata hairy roots

To study the possibilities for improvement of the ornamental character and production of secondary metabolites by using Wedelia trilobata hairy roots, we investigated the induction of W. trilobata L. hairy roots and its consumption changes of carbon resource, nitrogen resource, phosphate and calcium in the medium during liquid culture. The results showed that hairy roots could be incited from the cut edges of leaf explants 7 days after inoculation with Agrobacterium rhizogenes ATCC15834 and could have an au...