The history of EWAC - The European Cereal Genetics Co-operative (Part I)

Bread wheat Triticum aestivum (2n=6x=42) is an allohexaploid species carrying seven pairs of chromosomes from each of its three ancestral diploid parents. The allohexaploid constitution of bread wheat with its triplicated genetic information allows it to tolerate changes to its basic chromosome number. Riley and Kimber (1961) showed that 2 to 3% of the seed of commercial wheat varieties have altered or aneuploid chromosome constitutions. The aneuploids may show reduced or increased dosages of individual chromosomes or of chromosome arms (telocentrics). The most common form of aneuploids are monosomics that have a single chromosome missing (2n=41).

The pioneering work of Professor Ernie Sears in the 1950's first alerted the world to the benefits of using wheat aneuploids for research and breeding. Sears isolated complete series of aneuploids with several different chromosome constitutions in the variety Chinese Spring. These included monosomics (2n = 41), nullisomics (2n = 40), tetrasomics (2n = 44) and lines with various telocentric combinations (Sears 1953, 1954). Sears was also able to demonstrate how the monosomics could be used to identify which chromosomes carried a particular gene.

In further developments it was shown that once a monosomic series had been created in one variety, the monosomic could be transferred to a second variety by backcrossing (Sears 1953; Unrau 1958). In the second backcrossing scheme individual chromosomes from one variety could be individually transferred or substituted into a second variety providing very precise stocks for genetic analysis (Sears et al. 1957).

At the Plant Breeding Institute, Cambridge, UK, Professor Colin Law recognised that the task of developing the precise genetic stocks would be very time-consuming and laborious. To overcome these difficulties, he proposed that an informal organisation known as the 'European Wheat Aneuploid Co-operative´ (EWAC) should be set up to co-ordinate the European development and utilisation of wheat aneuploids (Riley and Law 1966).

In 1967 an inaugural meeting of EWAC was held in Cambridge, UK to set out a framework for the collaboration of European Wheat cytogeneticists. The meeting was attended by 49 participants from 22 countries. The meeting agreed on six key points for future co-operation that comprised:
1) The prevention of duplicated effort in development of plant material or the extraction of information.
2) The European exchange of information to ensure that the maximum benefit is derived from aneuploid studies.
3) Free exchange of cytogenetically verified stocks.
4) Joint work to be undertaken to develop plant material that will yield the maximum agricultural and scientific benefits.
5) Co-operative study and testing of lines in a range of environmental conditions.
6) Arrangements for training in the techniques and application of aneuploid methods.

Part II »