Principles of Plant Genetics and Breeding

22 CHAPTER 2
cultivation in areas as far north as Canada or
Scandinavian countries, which have a very short
warm season. After several years in one experimental
or breeding station, adapted populations can be
moved northwards for adaptation to a shorter summer.
In this way, new varieties of corn, adapted to
these new environments, and with a very short
cycle length, have been developed. Many other
examples exist, and the gardens or experimental
stations for adaptation have played a major role in
the successful introduction of new crops.
Not all crops have the same possibilities of being
introduced as a new crop into a region or country.
The introduction needs a previous study of the suitability
of the new crop to the new conditions. It is
essential to evaluate its adaptation to agroecological
conditions and the potential market, and it is
Figure 2 The breadfruit (Artocarpus altilis), a crop that was the also important to collect information on the man-
subject of some fascinating expeditions to the Polynesian islands agement of the crop in its region of origin. All this
in order to obtain propagation material to introduce it as a new information will be useful in identifying potential
crop in the Western Indies.
growing areas because, frequently, a crop displays
its optimum performance under a limited range of
environmental conditions.
The next step is to conduct preliminary field plot research. The goal is to test or develop genotypes or varieties with satisfactory
adaptation and to obtain basic information about the production practices and pests and diseases affecting the
new crop. A critical aspect deals with the use of sufficient genetic variation in the trials. Many attempts to adapt a new crop
to a new region have failed because of the use of limited genetic variation (one or two cultivars). In this way, different
genotypes show different behaviors under the same environmental conditions, and this may allow for the selection of individuals
or populations with the most satisfactory behavior (i.e., exploiting genotype × environment interaction) either for
direct cultivation or as a starting point for breeding programs. Another key point is identifying growing techniques that can
improve the productive potential of the new crop.
After this, a more extensive evaluation should be conducted. This usually needs the involvement of growers and industry
and the technical assistance of research centers. Basically, it deals with trials to evaluate the performance of adapted
plant material at different locations of the potential production area, as well conducting postharvest research and marketing
studies in order to determine the best marketing channels. Finally, if results are promising, the product can be released.
The development of a new crop is a slow and complex process with uncertain results. Several cases show that investment
in the introduction and adaptation of new crops may be highly profitable and returns in new crop research are, as a whole,
many times higher than the investment. The introduction of soybean in the USA from China is the story of one such success.
Nowadays, the USA is the main producer of soybean in the world. This plant was introduced in the 18th century and its
interest as a crop began at the end of the 19th century in several agricultural experiment stations. The development of soybean
as a new crop cost American taxpayers US$5 million from 1912 to 1941. However, US soybean export trade in 2000 alone
was estimated at $6.6 billion. Another example comes from kiwifruit introduction into New Zealand. This exotic and halfdomesticated
plant was first introduced into New Zealand from Chinese forests at the beginning of the 20th century and
was cultivated as an ornamental until the 1950s. Finally, New Zealand growers decided to exploit its potential as an exotic
fruit in the 1960s and 1970s. From that moment on, this crop has provided “kiwi” growers with very high profits, particularly
in the 1970s and 1980s, when kiwifruit production and marketing were performed exclusively by New Zealand.
Currently, kiwifruit is the biggest horticultural export in New Zealand with a total value of about NZ$600 million (US$250
million). These are only two examples of how research on new crops has been very profitable, but many others exist.
Further reading
Janick, J. (ed.). 1996. Progress in new crops. ASHS Press, Arlington, VA.
National Research Council. 1989. Lost crops of the Incas: Little-known plants of the Andes with promise for worldwide
cultivation. National Academy Press, Washington, DC. 428 pp.
Vietmeyer, N.D. 1986. Lesser-known plants of potential use in agriculture and forestry. Science 232:1379–1384.