Main content area

Plant regeneration via organogenesis in the Korean and Japanese winter squash (Cucurbita maxima)

Lee, Y.K., Chung, W.I., Ezura, H.
Acta horticulturae 2002 no.588 pp. 299-302
Cucurbita maxima, adventitious shoots, benzyladenine, cotyledons, cultivars, diploidy, explants, flow cytometry, germination, growth regulators, organogenesis, pumpkins, seedlings, winter squashes
Using cotyledonary explants excised from seedlings after in vitro germination, plant regeneration via organogenesis was established for Korean and Japanese pumpkin (Cucurbita maxima) cultivars. To establish optimal conditions for adventitious shoot induction, a variety of explants were prepared from seedlings of different ages, and cultured using different media and different concentrations of growth regulators. For both cultivars, plant regeneration was optimal when the proximal parts of cotyledons from 4-day old seedlings were cultured on induction medium composed of Murashige and Skoogs (MS) medium with 1 mg/L 6-benzylaminopurine (BA). After 3 weeks of culture in the induction medium, 82% of Korean explants and 86% of Japanese explants regenerated shoots. The adventitious shoots were subcultured on elongation medium composed of MS medium with 0.1 mg/L BA, and the elongated shoots were successfully rooted in MS medium without growth regulator for 2 weeks. Flow cytometry analysis revealed that most of the regenerated plants were diploid. These results demonstrate that this regeneration technique is useful for pumpkin transformation studies.