Research was undertaken to optimize propagation of the southern China native Camptotheca acuminata Decaisne, source of the medicinal compound camptothecin that is used in the treatment of multiple forms of cancer and other diseases. The study focused on cutting propagation, micropropagation, and seed storage. Softwood cuttings of C. acuminata rooted readily in intermittent mist (4 sec on every 6 min.) in coarse vermiculite when treated with K-IBA (indolebutyric acid, potassium salt) quick dips ranging from 4.14 mM to 37.3 mM, with a 29.0 mM quick dip (5 sec.) promoting 82% rooting with little foliar damage. Actively growing shoot tip explants were tissue cultured on media containing Murashige and Skoog, Gamborg's B5, and Woody Plant Medium (WPM) salts in factorial combinations with BA (benzyladenine). WPM containing 4.44 μM BA promoted excellent shoot proliferation; microcuttings were rooted, acclimated, and grown in the greenhouse. Seeds stored in polyethylene bags in a refrigerator (4°C) or freezer (-20°C) maintained good germination (81% and 80%, respectively) while seeds stored at room temperature (25°C) in polyethylene bags lost germination ability quickly (58%) after one year of storage. C. acuminata is readily adaptable to modern nursery techniques for either vegetative or seed propagation.

Camptotheca acuminata Decaisne (Nyssaceae) is endemic to China. The plant was brought to the United States only on a few occasions and thus can be considered rare in this country. A search of the plant kingdom for species that produced anticancer substances revealed that ethanolic extracts of Camptotheca acuminata had such a property. The active constituent was identified eventually. Further testing and possible marketing of the active principle, and alkaloid, (camptothecin) depended on a combination of factors: obtaining the plant from China, organization of a mass planting program in the United States or chemical synthesis of the drug. Due to the dissention between China and the United States during this period, (1950-1960’s) the first alternative was ruled out. Planting programs were organized but the plant needs a relatively long time to mature. Attempts to synthesize camptothecin were started but success was not immediate and there was no guarantee of ever achieving synthesis. As an alternative to these methods, the author of this research proposed an in vitro system of obtaining the drug. The plant would be grown in culture and the active principle extracted. The complete story of camptothecin, the rationale for in vitro culture in general and the methods and results of this project are given in the following chapters.