Start Date
2-28-1985 2:30 PM
Description
Alfalfa (Medicaao sativa) is a native of an area south of the Black and Caspian seas and it still grows wild in Iran and eastern Anatolia. Alfalfa was the chosen forage for the fighting horses of ancient armies as long ago as 1800 B.C. when the Kassites conquered Babylon. The spread of alfalfa followed the pathway of armies through the Mediterranean, Europe, and the New World. For ages before man used alfalfa to fuel his fighting animals natural selection processes worked on the evolution of alfalfa and its predecessors. A scenario which would account for the morphology and physiology of alfalfa is as follows. Alfalfa evolved in a climate similar to that which it is best adapted. Under these conditions alfalfa would be subjected to periodic grazings as flocks or herds moved in migratory patterns. During stress periods plants which avoided drought or cold damage had an advantage and survived. Concurrently, possibly because of the low nitrogen status of the soils, symbiotic nitrogen fixation coevolved, This latter characteristic is often associated with plant colonizers. In more recent times the natural selection pressures were modified by man but the fact remains that evolution of alfalfa was primarily influenced by grazing herbivores, and was not affected by man until recently. Evidently the selection pressures under grazing were consistent with our modern management of alfalfa for hay or silage crops.
Included in
Grazing Alfalfa
Alfalfa (Medicaao sativa) is a native of an area south of the Black and Caspian seas and it still grows wild in Iran and eastern Anatolia. Alfalfa was the chosen forage for the fighting horses of ancient armies as long ago as 1800 B.C. when the Kassites conquered Babylon. The spread of alfalfa followed the pathway of armies through the Mediterranean, Europe, and the New World. For ages before man used alfalfa to fuel his fighting animals natural selection processes worked on the evolution of alfalfa and its predecessors. A scenario which would account for the morphology and physiology of alfalfa is as follows. Alfalfa evolved in a climate similar to that which it is best adapted. Under these conditions alfalfa would be subjected to periodic grazings as flocks or herds moved in migratory patterns. During stress periods plants which avoided drought or cold damage had an advantage and survived. Concurrently, possibly because of the low nitrogen status of the soils, symbiotic nitrogen fixation coevolved, This latter characteristic is often associated with plant colonizers. In more recent times the natural selection pressures were modified by man but the fact remains that evolution of alfalfa was primarily influenced by grazing herbivores, and was not affected by man until recently. Evidently the selection pressures under grazing were consistent with our modern management of alfalfa for hay or silage crops.