Title: Wheat breeding for varietal mixtures for increased yield and yield stability
Funded by: Promilleafgiftsfonden for landbrug (Danish Agriculture Levy Foundation)
AU project manager: Associate professor Bjarne Nielsen (QGG)
Project period: 1 January 2024 - 31 December 2025
Funding amount: 2024: 587,000 DKK. 2025: TBA
Project description:
Purpose: To estimate the genetic correlation between yield of wheat when varieties are grown respectively as single varieties and in variety mixtures. The yield potential for the individual wheat varieties is expected to be different depending on whether they are used in a variety mixture or grown individually.
Activities: TystofteFonden is responsible for the Danish variety testing, and since 1994, varieties of wheat have been used as a reference variety in the variety testing. Yield data from these trials will be used together with genotyping data of wheat varieties and lines provided by the breeding company Nordic Seed. By combining genotyping data for the wheat varieties with yield data, we can estimate genetic correlations between yield of varieties when grown in pure culture and in variety mixtures. The genetic correlations will be a gain for wheat breeding in the efforts to meet the future need for better and more robust varieties for the benefit of Danish farmers. On the basis of the analyses, we will propose a recommended genetic profile for variety mixtures that are expected to give the greatest possible yield and yield stability.
The multi-trait models to be used will also include correction for environmental effects across location and year. Thereby, the so-called GxE effects can be estimated, which form the basis for examining different variety mixtures for their genetic yield potential and stability across years and locations in Denmark. In order to maximize the genetic gain over time for varietal mixtures, we will develop a selection index for yield based on cultivation in both pure stock and in varietal mixtures of the different wheat varieties.
Effects: The results from the project will provide 1) increased breeding progress for variety mixtures, 2) new knowledge about whether variety mixtures have increased yield stability compared to pure varieties, 3) a breeding value figure for varieties when they are used in variety mixtures 4) recommended genetic profile for variety mixtures 5) a combined selection index for breeding values for varietal mixtures and single varietal cultivation.
