Micropropagation and synthetic seed in M.26 apple rootstock (II): A new protocol for production of encapsulated differentiating propagules

Synthetic seed technology is an alternative to traditional micropropagation for production and delivery of cloned plantlets. Several aspects of the technique are still underdeveloped and hinder its commercial application. One of these aspects is the high hand labor requirements and costly procedures for the production of encapsulated explants. Direct organogenesis is an efficient shoot regeneration method and uninodal explants can be used for encapsulated synseed production. In this paper, we compare the performance of encapsulated organogenetic explants of M.26 apple rootstock that were prepared by hand and mechanical manipulation. Conversion of synseed into plantlets was 25% from encapsulated hand-cut uninodal microcuttings and 11% from machine-ground explants. The results demonstrate that synthetic seeds of M.26 apple rootstock can be produced through organogenesis from machine processed explants followed by root induction and encapsulation of differentiating propagules.