The Large Genome Collider: Wide Hybrids and the Making of Apomixis
Prof Steve Hughes, Co-Director, Egenis and
Dr Matt Hodges, Research Fellow, Egenis
University of Exeter, Byrne House, St Germans Road, Exeter, EX4 4PJ,
Room no: GF7, Byrne House
Time: 3:30 - 5:00 PM
The natural formation of hybrids within and between taxonomic groups has been a common feature in the generation of diversity during evolution, especially in the plant kingdom where the opportunity for stabilisation of disparate genomic constitutions via polyploidy is most manifest. The most cited example is the hexaploid wheat which provides our daily bread, within which three diverse grass-derived genomes travel in company. Where hybrid genomic constitutions are less compatible, stabilised progeny can be established via the reproductive mechanism of Apomixis, which effectively bypasses the normal sexual process and supports trans-generational conservation of an original hybrid constitution as a maternal clone or ‘apospecies’. Natural apomicts are most common in the plant world, but are also found among insects and birds.The seminar will report on the Egenis study of the abstraction and harnessing of Apomixis in relation to hybridisation in practical plant breeding, in settings characterised as both formal (commercial) and informal seed systems. It will also explore the significance of apomictic breeding strategies to a re-assessment of the status of biological diversity. In this context the key example will be the tropical forage grass Brachiaria, a diverse genus for which two novel wide hybrid apomictic cultivars (Mulato I and Mulato II) have recently been released to pastural management across large areas of South America and South Asia.