The roseleaf raspberry （Rubus rosifolius）can provide an additional source of income for farmers in Hunan，China. Photo：Feng Yingli

What are “underutilized” species？

The term underutilized species-referring to animals，crop plants，wild or semi-wild plants-applies to those species which appear to have considerable potential for use yet whose potential is barely exploited，if not totally neglected，in agricultural production. For example，there are numerous plants which are particularly well adapted to specific sites and agricultural production systems. This category includes crops like yams，the‘Inca wheat’quinoa，and many species of tropical fruits and vegetables.

The reasons for the underutilization of such species vary：it may be that their useful traits are not well known；perhaps there is little processing or marketing capacity，or a lack of interest on the part of agricultural research.“Taro”，the tuberous root of Colocasia esculenta is an example of a species overlooked by science. Although it is one of the staple foods in Africa，Asia and Latin America，there has been less research on taro than on asparagus.

Instead of “underutilized” species，the related terms “minor”，“local”，“neglected”，or “orphan” species are also used in literature. These terms all focus on certain aspects which restrict a wider use，for example the fact that they have been “neglected” by scientific institutions，or that they are of “minor” economic importance. Other authors have suggested the terms “alternative” or “promising” species to highlight their potential.

Trend towards uniformity

Until the beginning of the 20th century，a wide range of locally-adapted crop varieties and livestock breeds were available to f