Economic botany is the study of the relationship between people (individuals and cultures) and plants. Economic botany intersects many fields including established disciplines such as agronomy, anthropology, archaeology, chemistry, economics, ethnobotany, ethnology, forestry, genetic resources, geography, geology, horticulture, medicine, microbiology, nutrition, pharmacognosy, and pharmacology. This link between botany and anthropology explores the ways humans use plants for food, shelter, medicines, textiles, and more.
In a 1958 essay at the conference that founded the Society for Economic Botany, David J. Rogers wrote, "A current viewpoint is that economic botany should concern itself with basic botanical, phytochemical and ethnological studies of plants known to be useful or those which may have potential uses so far underdeveloped. Economic botany is, then, a composite of those sciences working specifically with plants of importance to [people]." Closely allied with economic botany is ethnobotany, which emphasizes plants in the context of anthropology.
Botany itself came about through medicine and the development of herbal remedies. Thus at its advent, botany was economic as well as systematic. As plants became useful for herbals and curatives, their economic value increased. An early set of instructions drawn up by a cosmographer of Charles the fifth instructed explorers to
"determine what are the items of sustenance of the land and which ones are generally used, whether fruits or seeds, and all manner of spices, drugs, or whatever other scents, and find out the time in which one can reproduce the trees, plants, herbs, and fruits that these parts offer, and if the natives use them for medicines, as we do."
Teosinte and rice are two examples of plants modified so that their economic values would increase.
The teosintes are grasses of the genus Zea. Native Americans bred and selected teosinte for the traits we see in corn today (large ears, multiple rows of kernels). The first ears of maize were very short, with only 8 rows of kernels. Modern corn is the result of several thousand generations of selective breeding. Modern corn is incapable of reproducing without human help; the kernels will stay firmly attached to the cob and rot. This doesn't represent a useful adaptation for the species, but is excellent for harvesting and transporting corn.
Rice was first domesticated approximately 5,000 years ago, in Southeast Asia. Rice and American wild rice are believed to have been domesticated separately. Rice variants have been adapted to the tropics where they provide a grain staple, but rice can be grown almost anywhere. The introduction of dwarf rice variants made several rice-producing countries self-sufficient. Rice is suited to countries with high rainfall.