Functional Marker Development Across Species in Selected Traits

Abstract

Functional marker (FM) development across plant species requires common allelic sequences that affect phenotypic variation in the same way. The identification of orthologous genes showing the same function across species could indicate conservation of functional polymorphisms. In this chapter we provide an overview over polymorphic sites described within homologous genes across species directly related to selected traits, as well as the FMs developed and available for plant breeding. The review demonstrates that orthologous gene functions are conserved across species, making the targeted search for FM candidates genes an excellent approach for FM development across species. However, it is also reported that conservation of functional sequence motifs in those orthologous genes across species occurs as a rare phenomenon. Plasticity per se is highlighted as a new trait for plant breeding as robust, multi-stress tolerant and non-recalcitrant adventitious developmental character for plant production. As a conclusion of the review, new perspectives for the identification of functional markers across species are proposed.