Methods for Developing Perennial Grains

Three ways of developing perennial grain crops have been proposed:

  1. The primary gene pools of several domesticated grain crops include perennial types, even though these crops are generally grown as annuals. Pigeon pea is a large-seeded grain legume (pulse) with both short-season (annual) and long-season (perennial) varieties. If the highest-yielding annual varieties were hybridized with the longest-living varieties, robustly perennial, high-yielding varieties could be developed.
  2. The secondary or tertiary gene pools of most domesticated grain crops include perennial species. Gene exchange between such species is possible, though sometimes difficult. Genes enhancing the agronomic traits of wild perennials, increased seed size, for example, could be brought in from domestic grain relatives. Alternately, genes increasing the lifespan of domesticated grains could be obtained by crossing with wild perennial relatives. For example, domestic Asian rice can be crossed with wild perennial rice species to exchange genes for many traits.
  3. Wild perennial plants with oil-rich, carbohydrate-rich or protein-rich seeds could be domesticated without any wide hybridization. Although our grain crops were all domesticated thousands of years ago, modern genetic theory and molecular genetic techniques may greatly accelerate the process compared with the original process of domestication. The Rodale Institute and The Land Institute have each had plant breeding projects in which a wild, perennial grass, Thinopyrum intermedium was subjected to recurrent cycles of selection for improved grain traits.

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Perennial Grain".