Defined in the International Undertaking on Plant Genetic Resources (FAO, 1983) to mean the reproductive or vegetative propagating material of the following categories of plants:

(i) cultivated varieties (cultivars) in current use and newly developed varieties;

(ii) obsolete cultivars;

(iii) primitive cultivars (landraces);

(iv) wild and weed species, near relatives of cultivated varieties; and

(v) special genetic stocks (including elite and current breeder's lines and mutants).