Somatic embryogenesis on various potato tissues from a range of genotypes and ploidy levels

Abstract.

Somatic embryos (SEs) formed on in vitro-cultured stem internodes, leaves, microtubers and roots of 18 tetraploid potato (Solanum tuberosum L.) cultivars, diploid and monoploid germplasm and three wild Solanum species. A two-step protocol with 6-benzylaminopurine or thidiazuron in the first medium, and zeatin, indoleacetic acid and gibberellic acid in the second medium produced SEs within 14–28 days. SEs developed through the globular, heart and torpedo stages to produce thin-stemmed plantlets resembling potato seedlings. Plantlets transferred to the greenhouse produced greenhouse tubers. Secondary SEs were observed at the base of germinating torpedo-stage SEs in culture. SEs formed on stem internode sections, leaves and microtuber slices of in vitro-grown plants. Genotypic differences in regenerative capacity were clearly evident.