Harlan’s Crops and Man: People, plants and their domestication

Authors: STALKER, THOMAS - North Carolina State University; Warburton, Marilyn; HARLAN, JACK - Retired ARS Employee

Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 3/13/2020
Publication Date: 4/20/2021
Citation: Stalker, T.H., Warburton, M.L., Harlan, J.R. 2021. Harlan’s Crops and Man: People, plants and their domestication. 3rd edition. Madison, WI: Crop Science Society of America. 320 p.

Interpretive Summary:

Technical Abstract: This book is a classic that has been read by Plant Science students since the 1070s. Despite the release of a second edition by the author, Jack Harlan, in the 1990s, the book is again badly out of date. The Crop Science Society of America commissioned Tom Stalker, a graduate student of Jack Harlan, Marilyn Warburton, Editor of Crop Science, to update the book. First Edition, 1975: It has been nearly a half century since the great Russian agronomist, N.I. Vavilov, started writing and formulating theories about the origin of cultivated plants. It will soon be nearly 100 years since Alphonse de Candolle wrote his first book on the subject. The time has come for a third round of summary on what is known about crop origins. Vavilov had an opportunity to correct some of the errors that de Candolle had made and to add details of information that had recently become available. It will be my opportunity to correct some of the errors of Vavilov and to add additional information. I shall, of course, produce errors of my own and confess to ignorance of many crops. But each round has approached the truth a little more closely than the former, and bit by bit we are coming closer to a fuller understanding. The next round may well be the best and possibly the last for the evidence is disappearing. Gene centers or centers of diversity are disappearing before our eyes. The ancient traces of plant migrations through the ages are being obliterated by massive importations of new seeds and new materials. Ancient landrace populations are being abandoned in favor of modem, high-yielding varieties, and some old crops are being completely eliminated. It is already almost impossible to assemble meaningful information on the origin and evolution of certain crops as the evidence dims and fades away with each passing year. The origin and evolution of a few cultivated plants have come into sharp focus in recent years. New studies have been launched on near relatives, their distribution, their ecological behavior, and their genetic interaction with the cultivated races. These patterns have been studied in depth, and the pictures emerging have been relatively clear. Sometimes they have been supported and amplified by direct archaeobotanical evidence. For example, carbonized seeds or identifiable plant impressions have been found in sites reasonably well dated by carbon-14, and sequences of dated sites with plant remains often reveal details of evolutionary history. Some of the mysteries remain. We still do not know the origin of sesame, there are doubts about the pigeon pea, and the bottle gourd poses some interesting problems. How a genome of Old World cotton came to be incorporated into American cotton has not yet been resolved. How did the American sweet potato become widely distributed in the eastern Pacific by the time of Captain Cook*s voyages in the 1770s? Pre-Columbian distribution of the coconut remains rather obscure and the reasons for numerous vicarious domestications generate more speculations than answers. Recent cytogenetic research has called into question the significance of chromosome pairing and the nature of polyploidy. For several decades wheat has been singled out as a classical case of alloploidy. It has become increasingly clear, however, that while wheat is a polyploid it is not classical in the textbook sense. The genomes are not as clear-cut as we thought, pairing is demonstrably under genetic control, and there is increasing evidence that the B genome has not been properly identified. Indeed, the B genome in wheat may not exist outside of wheat. New and intensive research on the origin of maize has essentially destroyed the well-known tripartite theory of Paul C. Mangelsdorf and Robert G. Reeves. There is no reason to postulate a wild maize that later became extinct. Teosinte is wild maize, but whether teosinte, as we know i