Sex determination genes and their use in breeding

A method for self-fertilisation or intercros sing of dioecious plants wherein one or both of the parent plants is a plant in which the functional expression of the dominant suppressor of gynoecium development is disrupted or reduced.

A method to produce a plant in which the functional expression of the dominant suppressor of gynoecium development is disrupted or reduced which method comprises inhibiting the expression of the GDS gene.

A dioecious plant in which the functional expression of the dominant suppressor of gynoecium development protein is disrupted or reduced.

A method to improve breeding in dioecious plants which method comprises providing a plant in which the functional expression of the dominant male stimulator is restored and introducing said plant in inbreeding, backcross breeding, recurrent backcross breeding or double haploid breeding techniques.

A method to improve breeding in dioecious plants which method comprises a plant wherein the lack of functional expression of the dominant male stimulator is complemented by a functional copy of the dominant male stimulator and introducing said plant in inbreeding, backcross breeding, recurrent backcross breeding or double haploid breeding techniques.

A method for self-fertilisation or intercros sing of dioecious plants wherein one or both of the parent plants is a plant in which the lack of functional expression of the dominant male stimulator is restored or complemented by a functional copy of the dominant male stimulator.

A method for in vitro androgenesis wherein the plant used for providing anthers is a plant_in which the lack of functional expression of the dominant male stimulator is restored or complemented by a functional copy of the dominant male stimulator.

A protein that is able to suppress gynoecium development in asparagus plants comprising the amino acid sequence of SEQ ID NO:

• 2 or an ortholog or functional homolog thereof.

A protein that is able to provide masculinization in a plant from a dioecious species, comprising the amino acid sequence of SEQ ID NO:

• 5 or an ortholog or functional homolog thereof or a fragment thereof.

A method to improve breeding in dioecious plants comprising providing a feminized plant and introducing said plant in inbreeding, backcross breeding, recurrent backcross breeding or double haploid seed production.

A method to improve breeding in dioecious plants comprising providing a defeminized plant and introducing said plant in inbreeding, backcross breeding, recurrent backcross breeding or double haploid seed production.

A method to improve breeding in dioecious plants comprising providing a masculinized plant and introducing said plant in inbreeding, backcross breeding, recurrent backcross breeding or double haploid seed production.

A method to improve breeding in dioecious plants comprising providing a demasculinized plant and introducing said plant in inbreeding, backcross breeding, recurrent backcross breeding or double haploid seed production.