Strawberry (Fragaria ×ananassa cv. Camarosa) was evaluated to determine a high-frequency shoot regeneration response for leaf and shoot-tip explants. For direct organogenesis from strawberry leaves, combinations of moderate concentrations of thidiazuron [TDZ (0, 2, and 4 μm)] and 6-benzylaminopurine [BAP (0, 4, and 9 μm)] added into medium containing Murashige and Skoog (MS) basal salts were compared. The most shoots regenerated per leaf explant were observed with 4-μm TDZ. Regeneration from shoot tips was evaluated with 0-, 2-, 4-, 8-, and 16-μm zeatin, kinetin, or 6-α,α-dimethylallylamino purine (2ip) tested individually. Optimum shoot proliferation was achieved from shoot-tip explants on medium containing 4-μm zeatin. Rooting was best without cytokinins in the medium; however, adequate rooting was obtained on the 4-μm zeatin treatment as well.
Fatemeh Haddadi, Maheran Abd Aziz, Hossein Kamaladini and Seyed Ali Ravanfar
Fatemeh Haddadi, Maheran Abd Aziz, Ghizan Saleh, Azmi Abd Rashid and Hossein Kamaladini
An efficient micropropagation system for strawberry cv. Camarosa was developed. Sterilized runner tips were cultured on hormone-free Murashige and Skoog (MS) medium with 3% sucrose, 1 mL·L−1 Plant Preservative Mixture, and solidified using 0.25% phytagel to produce in vitro stock plants. Shoot tips derived from the in vitro stock plants were cultured on MS media containing 0, 2, 4, and 8 μM thidiazuron (TDZ) and 0, 4, 9, 18, and 27 μM N6-benzylamino-purine (BAP) for shoot induction. Shoots produced on the best shoot induction medium were rooted on MS media containing 1, 2, 3, and 5 μM of either indole-3-butyric acid (IBA) or naphthaleneacetic acid (NAA). Results showed that MS medium with 2 μM TDZ and 4 μM BAP was optimum for shoot multiplication from the shoot tips. The most suitable medium for inducing the highest number of roots per explant, the highest percentage of explant with roots, and the highest mean root length were 1 μM NAA, 1 μM IBA, and hormone-free MS medium, respectively. Plantlets were transplanted into substrate consisting of perlite + vermiculite + cocopeat (2:1:2 v/v/v) resulting in 90% survival. After 1 month, plants were irrigated using Hoagland's solution and runners were produced after 3 months.