Sunflower rust is caused by Puccinia helianthi Shw. and is an important disease in Argentina, Australia, Canada, Egypt, Israel, Turkey, USA and the former USSR. Sunflower rust is a macrocyclic, heterothallic and autoecious fungus, surviving mainly in plant debris in soil in the form of teliospores. New races of P. helianthiare continuously evolving and overcoming resistance genes, resulting in a continuous threat for the crop. The deployment of hybrids with simple resistances has exacerbated this problem. Combination of the appropriate R-genes could result in a resistance more difficult to overcome. The identification and characterization of new durable sources of sunfl ower rust resistance is a high priority for both researchers and industry. There is a possibility of breeding for high coumarin content to improve resistance at early stages of fungal development.

Peer Reviewed