NAn international team of researchers, including geneticists from the University of Giessen, has gained new insights into the genome of a valuable vegetable protein source: The scientists have succeeded in completely sequencing the genome of the modern broad bean variety “Tiffany”. Broad beans can be grown in an insect-friendly manner and require little fertilizer. So far, however, only little breeding progress has been made with this useful plant. This is also due to their exceptional genetic makeup.
Field beans only have six pairs of chromosomes; human cells have 23. However, with almost four billion base pairs, one of the bean chromosomes contains more DNA than the entire human genome and is one of the largest chromosomes of all. The complete sequencing of the field bean genome was therefore considered impossible for a long time, as the Liebig University writes.
Identified genes for seed size and constituents
The research group led by Giessen agricultural bioinformatician Agnieszka Golicz has now succeeded in assembling the complete genetic information from long sequence pieces. The scientists published their results in the journal “Nature”. They compared the sequences with the genome of an older broad bean variety and were able to identify genes that carry information for important characteristics such as seed size and components.
The geneticists also determined that so-called transposons spread rapidly in the genome of the broad bean. These are short DNA sequences that “jump” within the genome. This leads to the duplication or deletion of genes, which can increase the adaptability of the plants. “By providing the genome, we are now in a position to breed field beans in a more targeted manner to meet the challenges of climate change and to secure cultivation as a valuable, domestic source of plant protein in the future,” says Rod Snowdon, Professor of Plant Breeding at the University of Giessen. His colleague Golicz now wants to decode the genomes of many other broad bean varieties.