Abstract

Most commercial breeding companies do not include improved weed competitive ability (WCA) as a specific breeding goal. One reason for this is that WCA is not tested for in the official testing and is therefore difficult to use as a sales argument; another is that the trait is very complex and is hence difficult to breed for. With increased organic production the interest in cultivars with high WCA has increased and so has the interest among breeders. Some 15-20 years ago I studied various traits that might explain the variance in WCA in the breeding pool of Swedish barley and wheat and came to the conclusion that the two most important ones were early vigour growth and allelopathy. During the following years I have confirmed the usefulness of these traits in practical breeding programs with a special interest in wheat. Wheat is more important than barley in organic production but unfortunately it has a lower WCA than barley. In Swedish spring wheat for instance the allopathic properties are poor. A screening of 813 cultivars from a world collection revealed a few cultivars with a potential allopathic activity similar to that in barley. One of these was used in a breeding program resulting in lines with twice the activity of the Swedish parent and giving only half the weed biomass in the field plots. Unfortunately, there was also a yield penalty of 20%. In winter wheat the source of both early vigour and allelopathy was introduced from rye. The work with these wheat-rye translocation and substitution lines is still ongoing with the introduction of rye genes in more modern gene backgrounds. Parts of the materials in spring wheat and winter wheat are now further evaluated in the CORE II organic project Cobra.

Keywords

Early vigour, allelopathy, cereals, weed competitive ability

Published in

Title: Organic agriculture, clues for weed prevention and control : book of abstracts
Publisher: Universida de Vigo

Conference

Organic Agriculture: clues for weed prevention and control.

SLU Authors

• Bertholdsson, Nils-Ove

  • Department of Plant Breeding, Swedish University of Agricultural Sciences
    

Associated SLU-program

Cross-programme


UKÄ Subject classification

Agricultural Science
Genetics and Breeding


Permanent link to this page (URI)

https://res.slu.se/id/publ/59868