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Europe. ¹⁰ Existing collections need to be maintained, and the diversity of oca from distinct geographical areas systematically evaluated. In this, as in many Andean crops, there is great potential for international cooperation.

To aid in the wider testing, procedures for “virus cleaning” should be publicized, ¹¹ and selections of virus-free clones made available for direct use in the Andes, Mexico, and New Zealand, as well as for experimental trials elsewhere. Institutes, corporations, and nurserymen, both inside and outside the oca-growing nations, can foster this.

Attention should be paid to advances already made by Andean researchers. Individual plants should be closely examined for uniformity, growth patterns, and desirable tuber qualities such as size, shape, shallow eyes, and color.

There is much genetic diversity in this crop. However, flowering and seed set are uncommon, which limits the opportunities for genetic improvement. Techniques for seed production are needed. Without them, breeding will be slow and difficult.

Trial shipments of New Zealand oca have been turned away by U.S. agricultural inspectors on the grounds that the tubers “look like potatoes.” If export trade is to be developed, the possibility of introducing diseases to the potato industry will have to be resolved. Oxalidaceae and Solanaceae are not closely related families, and oca viruses probably will not affect potatoes. Research is needed to settle the question, one way or the other.