Ug99 race of stem rust pathogen: Challenges and current status of research to sustain wheat production in India

Abstract

Stem or black rust, caused by Puccinia graminis Pers.f.sp. tritici Errikss.and Henn. is infamous for causing severe losses to wheat (Triticum aestivum L. and T. turgidum var. durum) production. The causal organism of stem rust was named Puccinia graminis in 1797 by Persoon and the first detailed reports about this pathogen were given independently by Italian scientists Fontana and Tozzetti [1, 2]. Stakman and Piemeisel [3] showed that stem rust pathogen had various forms or races. Many devastating epidemics of wheat are reported to have occurred around the globe by this pathogen. Notable among these were the epidemics of North America in 1904 and 1916. A series of stem rust epidemics in the middle of 20th century led to the initiation of the International Spring Wheat Rust Nursery Program in 1950 by B.B. Bayles and R.A. Rodenhiser of USDAARS (United States Department of Agriculture - Agricultural Research Service). Subsequently, this nursery became the foundation of numerous other international nurseries and led to global cooperation to achieve resistance to diseases and pests of several crops.