Preliminary investigation into the solasodine yield from Solanum aviculare and Solanum laciniatum at 5 sites in the North Island, New Zealand

Abstract

Trial plantings of the solasodine-producing species Solanum aviculare and S. laciniatum (poroporo) were made at 5 sites in the North Island of New Zealand. Dry weight yield, solasodine production, and overwintering survival were determined. S. laciniatum consistently grew better and produced more solasodine than S. aviculare. However, the latter species can give higher solasodine concentrations, an important factor in the economics of alkaloid extraction and purification. Establishment of transplants at Rukuhia (Waikato) was difficult because of a late frost but, later, both this site and Manutuke (Poverty Bay) produced satisfactory yield from both species. At Wairakei, climatic factors severely restricted growth. Individual site effects, rather than climatic conditions, reduced growth in the Hastings and Ruakaka trials. Although commercial extraction of solasodine has occurred only in Taranaki Province, the warm zone areas of the Waikato, Poverty Bay, Hawke's Bay, and Bay of Plenty would all appear climatically and edaphically suitable as alternative sites for cultivation of the solasodine-producing species.

Keywords:

• solasodine
• poroporo
• Solanum laciniatum
• Solanum aviculare
• climatic suitability
• growth