Absolute vs relative dating techniques
No barley variety is adapted to all environments and, in fact, very different gene pools have evolved in the major barley production areas of the world.The gene pools may be defined by essential physiological parameters that determine adaptation to a production environment - such as vernalization and/or photoperiod response - or they may be defined by evolutionary bottlenecks and the accidents of history, such as regional preferences for two-rowed or six-rowed varieties.Barley should be grown under moderate nitrogen fertility conditions because high fertility will reduce kernel plumpness and increase lodging.The grain protein target for malting barley is 11.5% to 13%, which must also be considered in determining appropriate N fertilizer levels.
It is earlier in maturity than wheat and other cereal crops. Photo courtesy Patrick Hayes, OSU Requirements for inputs, particularly nitrogen, are relatively low.
In six-rowed barley, all of the florets are fertile (see the head on the left side of the picture).
The central seeds are round and fat, but the laterals tend to be slightly asymmetric.
It is grown in a range of extreme environments that vary from northern Scandinavia to the Himalayan mountains to monsoon paddies.
It is particularly noted for its tolerance to cold, drought, alkali, and salinity.