Bread Wheat is now the most widely cultivated wheat in
the world, grown in most temperate regions. Over many years,
newer varieties have been developed that have a greater
yield than many of the older traditionally grown wheat species.
This has led to a replacement of the traditional species
by bread wheat in some parts of the world, with a subsequent
loss of the older types from cultivation. The loss of species
diversity may mean that some useful characteristics, such
as fungal resistance or lodging resistance, could become
unavailable to scientists creating new varieties. Seed banks,
such as those held by the John
Innes Centre, custodian of the UK's cereal genetic resources,
are therefore important for maintaining reserves of these
species for possible use in future wheat breeding programs.
In addition to the Triticum species
in the above table, another tetraploid wheat, Durum
Wheat (Triticum durum) is
widely cultivated in areas with mild winters and hot summers.
The ears are free-threshing with large, hard-textured grains
that produce a coarse textured flour, known as semolina,
when milled. After mixing with water to form a stiff dough,
it can be extruded into various shapes before being dried
to create a wide range of pasta products, including macaroni,
spaghetti and lasagne. When cooked, the starch in these
products absorbs water and softens but the high gluten content
ensures that they retain their original shape without dissolving.
Work by NIAB (National
Institute of Agricultural Botany) to increase the genetic
diversity of Bread Wheat has used Durum
Wheat as the tetraploid source. Replicating the hybridisation
that occurred about 8,500 years ago in the Evolution
of Bread Wheat, a selection of wild diploid Goat Grasses
have been used to create new SHW's (Synthetic Hexaploid
Wheats). These have been examined for any improved commercial
advantages, such as improved fungal resistance or increased
yields, and if they would be suitable for creating new commercial
The remaining species were more commonly cultivated in the
past, although often restricted to limited areas, such as
the Vavilovi Wheat of Armenia. A selection of these species
that have been grown at the Mill in previous years are included
in photographs showing the seed spikes in early July
and the ripened plants in August.
Return to "Cereals at the Mill"