An efficient in vitro regeneration system from different wild apple (Malus sieversii) explants

Area of Science:

• Plant Science
• Conservation Biology
• Horticulture

Background:

• Wild apple (Malus sieversii) is an endangered species.
• It represents a valuable genetic resource for apple breeding.
• Effective conservation strategies are crucial for its survival.

Purpose of the Study:

• To investigate the influence of different plant hormone concentrations on wild apple regeneration.
• To establish an optimal regeneration system for Malus sieversii from leaf and stem explants.
• To facilitate large-scale clonal propagation for conservation.

Main Methods:

• Leaf and stem explants from Malus sieversii seedlings were cultured.
• Various concentrations of thidiazuron (TDZ) or 6-benzylaminopurine (BA) combined with 1-naphthaleneacetic acid (NAA) were tested.
• Optimal conditions included specific hormone combinations, explant orientation, and pre-treatment for leaf explants.

Main Results:

• The most effective medium for leaf explant shoot formation was MS with 4.0 mg/L TDZ and 1.0 mg/L NAA.
• For stem explants, MS medium with 1.0 mg/L BA without NAA was optimal.
• Shoot multiplication and rooting were achieved using specific BA, NAA, and sucrose concentrations in MS and 1/2 MS media.

Conclusions:

• An optimized regeneration protocol for Malus sieversii was developed, yielding results within 2-3 months.
• This protocol is suitable for large-scale clonal propagation.
• The established system is vital for the conservation of this endangered wild apple species.