Hereditary qualities of plants crucial to healthy food

The variation in the biochemical composition of plants is to a large extent determined by their hereditary characteristics. This is the conclusion of a publication by Wageningen UR researchers appearing in Nature Genetics- on line on 4 June. The study brought together researchers from the Wageningen UR departments Wageningen University, Plant Research International and RIKILT – in a joint project within the research programme of the NGI Centre for BioSystems Genomics – and the state university of Groningen.

The findings make clear that plant breeders will be able to use crossbreeding to develop new plant varieties faster in the future, thanks to a combination of large-scale analyses of content substances, knowledge of the genetic background of plants and use of bioinformatics. Higher content of health-promoting substances and improved taste are examples of traits that could be bred for.

Until now, many scientists assumed that it would be extremely laborious to study the direct contribution of genetic background to biochemical composition. The influence of the environment on the composition of metabolites (content substances) was expected to be too large for this.

The new research showed that the presence of metabolites is to a large extent determined by the genetic composition of the plant. This was demonstrated in a population of Arabidopsis plants by using fast and extremely accurate equipment for analysing metabolites, good genetic maps and powerful bioinformatics and statistics tools. The researchers found that the hereditary characteristics played an important role for around 75% of the hundreds of examined metabolites.

Due to this proven importance of the genomic natural variation and thanks to recent technological developments, plant breeders will be able to use targeted crossbreeding in their breeding programmes and select for the desired metabolite composition already in the seedling stage. This makes it possible to develop plants with more health-protecting substances, for instance, or better taste, even if this involves multiple genes.

The researchers subsequently combined the results of different, related metabolites. They found it relatively easy to confirm a number of previously known biochemical pathways, and were able to clarify new steps within those pathways.

The combination of metabolite analyses and genetic maps is expected to become a key tool for the relatively young scientific field of system biology.