Genetic transformation will allow Cereal Disease Lab scientists to test the effects of individual genes on the growth and development of rust fungi as well as on their ability to overcome resistance. Part of the current research concentrates on finding genes that control the ability of the fungus to reproduce by producing the spores that it uses to start new infections. If Cereal Disease Lab scientists can find ways to block the function of those genes in infected plants, they will be able to stop rust epidemics before they cause damage to the crop. Another part of the rust molecular biology research compares the DNA from a wide variety of rust fungi to determine genetic similarities between rusts that parasitize different types of plants. By studying these relationships, Cereal Disease Lab scientists hope to better understand the evolution of parasitic ability.
Rust fungi live and reproduce only on living plants.
They have existed as parasites of plants through much of the history of evolution of plants on the surface of the earth. Although different rust species parasitize plants of nearly every type from ferns, to pine trees, to buttercups, to grasses, each rust species has a limited host range of one or two types of similar plant species. For example, the wheat stem rust fungus can live on wheat and related cereals and wild grasses. The only other type of plant that it successfully infects is barberry, where it completes the sexual part of its life cycle. Studying the molecular genetics of rusts and their evolutionary relationships may help explain how a specialized parasite such as stem rust came to spread its life cycle across two such different types of plants.