Malus zumi
is known as an excellent dwarfing apple
rootstock occurring in natural or arid/semiarid soil or
salina. Gene manipulation of
M. zumi through
transgenic technology can modify plant feature for
further improvement fruit tree production by grafting the scion on a transgenic rootstock. Here, we report the
establishment of an efficient, in vitro, shoot regeneration
system and
Agrobacterium tumefaciens
- mediated
transformation from the leaf explants for
Malus zumi
(Matsumura) Rehd. Leaf explants were infected with
Agrobacterium strains containing nptII and gus gene.
The highest frequency of shoot regeneration was
obtained on MS medium containing 500 mg l
-1
Lactalbumin hydrolysate, 30 g l
-1 fructose,
supplemented with 3.0 mg l
-1 BA, 0.2 mg l
-1 NAA.Using
fructose instead of sucrose significantly increases the
shoot regeneration and decreases vitrification. This
regeneration procedure was incorporated into an
Agrobacterium-mediated transformation procedure in
M. zumi. Kanamycin was an efficient selective agent for
selection. Pre-selection (5 days after co-cultivation)
improved the transformation efficiency. The emergence
of expected bands by PCR analysis and Southern blot in
transgenic plantlets confirmed the transformation of
foreign DNA into plant genome.
