Genetic variation in degradability of wheat straw and potential for improvement through plant breeding

The degradability of cereal straw is of importance when it is used for animal feed, biological means of bioenergy production such as bioethanol production and when it is incorporated in soil. We examined wheat straw from 106 different winter wheat cultivars representing the northwest European contemporary gene pool. The cultivars were grown at two different locations to assess the potential for breeding for improved degradability. The straws exhibited much variation in degradability ranging from 258 g kg−1 to 407 g kg−1 of dry matter. The heritability for degradability was estimated to 29% indicating a reasonable potential for response to selection. Inclusion of height as a regression-term, indicated that only a minor part of genetic differences are directly related to plant height and that improvements in degradability may be achieved without unacceptable changes in straw length. Finally, a lack of correlation between degradability and grain yield indicated that straw degradability may be improved through breeding without serious negative effect on grain yield.