Wild Genetic Resources of Minor Oil and Rubber Crops

Jojoba (Simmondsia chinensis (Link) C. K. Schneid), lesquerella (Physaria fendleri (A. Gray) O’Kane & Al-Shehbaz), and guayule (Parthenium argentatum A. Gray) originate from semiarid climate zones of North America; meadowfoam (Limnanthes alba Hartw. ex Benth., Limnanthes bakeri J. T. Howell, Limnanthes douglasii R. Br.) is endemic to the western part of California, Oregon, and Southern Canada and grows around vernal pools and seasonally wet areas. This chapter discusses historic and current uses, domestication efforts, breeding, and cultivation challenges and describes the conservation status of the crops’ genetic resources. Meadowfoam and guayule are already cultivated on a limited industrial scale. Jojoba and lesquerella are not grown commercially in North America but are economically important in countries beyond the Americas and are of particular interest to nations with extensive areas of arid lands. North America is an important source of wild genetic resources for these crops, and further efforts are needed to ensure their conservation.