FiBL Switzerland and Agroscope, together with Agridea advisory centres and the School of Agricultural, Forestry and Food Sciences HAFL, investigated bread wheat varieties to determine their yield and quality stability. The results show that the choice of variety must be adapted to the site and that high yield potential does not go hand-in-hand with a high protein content.
In low-fertility or extensive conditions such as are found in organic farming, nitrogen (N) limitation can lead to a decrease in grain protein content. Breeding strategies must therefore be developed to guarantee the protein content of over 12% that meets commercial requirements.
Although wheat breeding has created new, higher-performing varieties that use soil N more efficiently, the performance of some varieties varies according to site and is strongly limited in low-fertility conditions. Only a systematic analysis of the variability of wheat performances in different pedoclimatic conditions will enable a description of the agronomic properties of the varieties under less favorable conditions.
In their article in Swiss Agricultural Research (download it HERE), the research team has come to the following conclusions:
The performance of bread-wheat varieties varies according to the potential of the growing site. The systematic comparison of their yield- and quality stability allows us to make variety recommendations for site-adapted production and hence for a more efficient use of resources.
Despite its low yields on low-potential sites, the variety Molinera adapts perfectly to all soil types and exhibits a highly consistent protein content.
A variety such as Aszita lends itself well to extensive growing conditions, where it can showcase other agronomic or nutritional characteristics.
In the network of trials conducted on plots in French-speaking Switzerland, an optimum protein content was observed for sites with average yields (40-55 dt/ha).
An additional varietal study that also included marginal and extensive (low-input) sites could contribute to the recognition of varieties with special characteristics for organic farming.