Mineral nutrition and alkaloid accumulation in Solanum laciniatum and S. aviculare : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Science in the University of Canterbury [Lincoln College]

The development of steroidal drugs such as cortisone and the artificial sex hormones has led in recent years to an extensive search for raw materials for the manufacture of these compounds (Kreig, 1965). The most important contemporary source of steroids is diosgenin, the alkaloid obtained from the Mexican yam (Dioscorea mexicana) but the expanded demand for steroid alkaloids has stimulated a wide-spread search for sources of steroids other than that obtained from Dioscorea particularly in 'iron curtain' countries (Kreig, 1965). The best alternative to diosgenin is solasodine, the steroidal alkaloid found in some members of the genus Solanum (Applezweig, 1962). Two species - Solanum aviculture Forst. and Solanum laciniatum Ait. appear to be best suited to commercial production of solasodine and field trials involving these species. The alkeloids are formed in the shoot (Street, Kenyon and Watson, 1946) and accumulate mainly in the leaf mesophyll cells (Moskaleva and Goncarova 1963). Considerable variation in alkaloid content has been reported in the literature. Factors such as the geographic strain of the species, climate and cultural practices all have been shown to affect alkaloid levels. The purpose of this thesis was to investigate relationships between some aspects of mineral nutrition and growth and alkaloid production in S. aviculare and S. laciniatum