Genetic transformation of the apple rootstock M26 with the RolB gene and its influence on rooting

• Published in: Journal of plant physiology Vol. 153; no. 3; pp. 371 - 380
• Main Authors: Welander, Margareta, Pawlicki, Nathalie, Holefors, Anna, Wilson, Fiona
• Format: Journal Article
• Language: English
• Published: Elsevier GmbH 1998
• Subjects: Agrobacterium rhizogenes; genetic engineering; Malus X domestica; rolB; rooting; β-glucuronidase; Malus X domestica; β-glucuronidase; rooting; SDS; GUS; rolB; MS; CTAB; genetic engineering; NAA; kb; Agrobacterium rhizogenes; X-gluc; MUG; PCR; BA
• ISSN: 0176-1617; 1618-1328
• DOI: 10.1016/S0176-1617(98)80164-8

The apple rootstock M26 (
Malus ×
domestica Borkh.) was transformed using the binary vector pCMBB: GUS in the Agrobacterium tumefaciens strain C58C1. The vector contained the
nptII gene under the
nos promotor and a tandem gene construct of the
gus and the
rolB genes both under the rolB promotor. Two transformed clones were verified with PCR and Southern blot analyses. One clone contained all three genes, whereas in the other clone only
rolB and
nptII genes were integrated in the plant genome. Rooting experiments using both intact shoots and stem segments showed that integration of the
rolB gene increased auxin sensitivity and rooting ability compared with untransformed control shoots. GUS activity driven by the
rolB promotor was higly expressed in the root meristem but not in the extended root. In the shoot, GUS activity was confined to the procambial strands. In the bud, the leaf primordia showed rather intense uniform staining. During growth of the leaf the provascular cells of the midrib showed weak GUS expression and developed leaves were almost unstained.