The aim of the RYE-SUS project was the development, testing and modeling of gibberellin-sensitive semi-dwarf rye with improved lodging tolerance, high yield potential and improved drought tolerance. A total of 48 semi-dwarf experimental hybrids and their tall sister hybrids were developed and tested in multi-environment field trials, in Austria under organic conditions in the Marchfeld and under conventional management in the Waldviertel. In almost all cases, the semi-dwarf hybrids yielded less than their tall counterparts. In the Waldviertel, however, the semi-dwarfs showed no lodging at all compared to the medium to severe lodging of many tall genotypes. The lower grain yields of the semi-dwarfs were mainly due to a lower kernel weight, while tillering was even higher than that of the tall types. The dwarfing gene did not have a negative effect on quality characteristics. Ergot infestation was also not increased in the test hybrids compared to open-pollinating varieties. The dwarfing gene was introgressed into Austrian genetics by means of backcrossing. The crossbred offspring will be further selected by the involved project partners beyond the project duration in order to build up a new adapted gene pool. Furthermore, a reference trial with 24 varieties, released between 1876 and 2018, was established and tested over two years. With this nursery, a clear breeding progress could be shown, especially in the last 40 years, whereby the hybrid varieties are superior to the open-pollinating varieties, even under organic farming. Based on historical observations in Germany from 1983 to 2019, a life cycle assessment for the production of wheat and rye was calculated. It was shown that the greenhouse gas emissions and the carbon footprint per unit of harvested product from rye are smaller than those from wheat. Hybrid varieties showed higher greenhouse gas emissions per unit area, but a lower carbon footprint compared to open-pollinating varieties. Based on the created data, an existing crop model for wheat was adapted to rye. The recently published rye reference genome also enabled the identification of a number of previously unknown genes that contribute significantly to winter hardiness. |