Stripe rust is a disease of barley caused by the fungus Puccinia striiformis f. sp. hordei. It originated in Europe, but arrived in Colombia in 1975 and by 1980 was causing annual crop losses of 30 to 70% over much of South America. Later it spread northwards, reaching Mexico and the southern USA by the early 1990s, and at the time of writing (1995) had reached the northern border of the USA and was spreading into Canada. As none of the malting barley varieties grown in the USA and Canada have any significant resistance to this disease, it poses a serious threat to the supply of barley to these countries' malting industries. An international project to develop countermeasures, including resistance testing of barley breeding lines, microbiological studies of the different strains of the fungus, and trials of possible fungicide treatments (which seek to identify products which are not only effective against the fungus but also have a low environmental impact), has been set up by scientists in the USA, Germany, Bolivia and Ecuador. The results obtained up to the time of writing are presented.
Keywords : barley disease fungus research development