South African Avocado Growers ’ Association Yearbook 1990. 13:16-20 Future prospects with new avocado cultivars and elite rootstocks

Cultivation of avocado is in the early stages of domestication of this species as an orchard crop. Selection of cultivars has followed a typical evolutionary pattern for fledgling industries with the initial production of many varieties. With stringent evaluation this has subsequently diminished to two cultivars of major importance, Fuerte and Hass, in those countries growing Mexican and Guatemalan race avocados. These two have become the industry standards and form the bulk of the international trade in avocados. However, breeding programmes and field selection in California and other countries are producing a new generation of cultivars which we cannot afford to ignore. In Australia Shepard has become an important early maturing cultivar while internationally, speculation on the value of Gwen continues. The urgent quest for Phytophthora root rot resistance in avocado rootstocks has resulted in improved tolerance to this disease, viz Duke 7, Martin Grande and Thomas. However, selection of elite rootstocks has focused on disease resistance with productivity and other horticultural characteristics of trees being largely ignored. This article reviews our current knowledge of some new avocado cultivars and rootstocks