Bunt resistant winter wheat varieties for organic agriculture
Franziska Löschenberger, Almuth Elise Müllner, Hermann Bürstmayr
In connection with the SOLIBAM project and in collaboration with the ongoing COBRA project at IFA Tulln / BOKU Vienna (Institute for Biotechnology in Plant production) we selected a number of wheat lines containing the Bt10 bunt resistance gene, which were derived from U.S. bred variety Weston. These lines were tested for common bunt resistance in field trials and for the presence of Bt10, using the FSD/RSA marker (Laroche et al. 2000), the currently best available molecular marker for common bunt resistance. In parallel, these lines were tested in multi-location field trials for their agronomic performance under low input conditions. Based on the combined results, several lines could be identified as potential candidates for the official organic VCU test in Austria (Table 1). Two of these lines, SZD 5935 and SZD 5944, carry the Bt10 resistance gene and proofed to be resistant to common bunt in field trials and were therefore selected for the official organic VCU test in 2015/16. One line, SZD 5833, was identified to contain the Bt10 resistance gene; however, it did not proof to be resistant to common bunt in field tests. Still, this line will enter the official VCU test in 2015/16 due to its excellent quality characteristics (high protein content). One promising line, SZD 3611, included in the official organic VCU test already in 2014, will be withdrawn, as it tested negative for the Bt10 resistance gene and – in accordance with the marker results – was highly susceptible to common bunt in this year`s field trials. Currently, we can only test for the presence of Bt10, and – as depicted by the example of SZD 5833 – this marker is not fully predictable for bunt resistance under field conditions. This underlines the need for more reliable molecular markers, in order to test for bunt resistance. The ongoing COBRA project at IFA Tulln aims to map new bunt resistance genes in winter wheat and develop new molecular markers for application in wheat breeding for organic agriculture.
The project “COBRA Austria” is funded within the framework of the ERA-Net project Core Organic 2 by the Austrian Federal Ministry of Agriculture, Forestry, Environment and Water Management (project number 100898).
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