Anna Koltunow, CSIRO, Australia
Claudia Köhler, VBSG, SLU
Room A402, Uppsala BioCentre, Ultuna
13:00 - 14:00
Genetic and molecular control of asexual seed formation

The benefits of hybridity in plant breeding have been extolled for several thousand years.  In addition to superior yields (15-35%), hybrid crops often exhibit improved agronomic traits such as physical stability, higher responses to fertilizers, better root penetration and improved tolerances to drought and heat.  However, these multiple benefits of hybridity come at the cost of expensive seed production methodologies.  Hence, the use of hybridity in world crop production is currently restricted to a few crops in which hybrid seed can be economically produced, e.g., maize, sorghum, sunflower, cucumber and onion.  Yield potential and genetic diversity of other significant world crops utilizing homozygous inbred varieties including wheat, soybean, cotton and most rice, could be increased substantially if hybrid seed could be economically produced.  In nature, certain plant species form their seed asexually through a process termed apomixis.  Seed derived via apomixis germinate progeny that are genetic clones of the mother plant.  Accordingly, plant breeders would like to harness apomixis to produce hybrid seed, i.e., once a hybrid is induced to be apomictic, it would exponentially multiply itself cheaply through its own seed.  Unfortunately apomixis is not found in agriculturally important crops. We are studying the molecular regulation of apomixis in Hieracium to provide information to induce apomixis in crops.  In Hieracium,  apomixis replaces the sexual process of meiosis during female gamete formation and, fertilization is not required to form either the embryo or the endosperm in the seed. The developmental functions of the genomic loci identified controlling apomixis in Hieracium will be discussed.