Researchers from Kansas State University (K-State) have published the
results of their work that characterized numerous whet genesduplicated
thousands of years ago to understand how they control the crop's yield
and other desirable traits.

Led by Eduard Akhunov, wheat geneticist and director of K-State's Wheat
Genetic Resources Center, said his team's research may lead to greater
opportunities for breeders to perform �??targeted breeding�?� that can
increase grain size and number �?? ultimately increasing yields. They
studied the role of gene copies available from each of the
respectivegenomesin polyploid crops, those that contain more than two
sets of chromosomes, in shaping main agronomic traits. Bread wheat, he
added, is polyploid, formed nearly 10,000 years ago from merging the
genomes of two wild ancestors: tetraploid wild emmer wheat (which has a
genome formula known as AB) and diploid goatgrass (with genome formula
D). As a result, most genes in wheat exist in three copies, one from
each of the A, B, and D genomes said Akhunov.

In the current study, K-State researchers tested combinations of the
gene copies to see the impact they would have on wheat's growth and
productivity. The team found that there is a relatively small subset of
genes where copies from different wheat genomes are expressed at
different levels, referred to as an imbalanced expression of genes. This
turned out to have a positive effect on wheat, in many cases increasing
grain size, weight, and number. The K-State study suggests that over
many years, breeders have selected combinations of imbalanced genes that
positively impacted yield in diverse climatic environments.

K-State researchers uncover new clues for improving wheat
[www.ksre.k-state.edu]