Cultivated barley, Hordeum vulgare L., is considered to be a nonhost or intermediate host species for the wheat leaf rust fungus Puccinia triticina. Here, we have investigated, at the microscopic and molecular levels, the reaction of barley cultivars to wheat leaf rust infection. In the nonhost resistant cultivar Cebada Capa, abortion of fungal growth occurred at both pre- and posthaustorial st...

Quantitative adult plant resistance (APR) to stem rust (Puccinia graminis f. sp. tritici) is an important breeding target in wheat (Triticum aestivum L.) and a potential target for genomic selection (GS). To evaluate the relative importance of known APR loci in applying GS, we characterized a set of CIMMYT germplasm at important APR loci and on a genome-wide profile using genotyping-by-sequenci...

Stripe (yellow) rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most destructive diseases of wheat worldwide. Planting resistant cultivars is an effective way to control this disease, but race-specific resistance can be overcome quickly due to the rapid evolving Pst population. Studying the pathogenicity mechanisms is critical for understanding how Pst virulence changes...

Glyphosate is a broad-spectrum herbicide used for the control of weeds in glyphosate-resistant crops. Glyphosate inhibits 5-enolpyruvyl shikimate 3-phosphate synthase, a key enzyme in the synthesis of aromatic amino acids in plants, fungi, and bacteria. Studies with glyphosate-resistant wheat have shown that glyphosate provided both preventive and curative activities against Puccinia striiformi...

to evaluate the reaction of some wheat advanced lines and cultivars to yellow rust at seedling stage, seeds of 200 accessions were planted in 5cm diameter pots (4-6 seeds per pot) in greenhouse. the seedlings were inoculated with fresh harvested urediniospores of two different races of puccinia striiformis f.sp. tritici (134e134a+ from karaj and 134e142a+ from maragheh, iran) when the first see...

Stem rust (caused by Puccinia graminis Pers.:Pers. f. sp. tritici Eriks. & E. Henn.), a devastating disease of wheat (Triticum aestivum L.), was effectively controlled worldwide for the past 50 yr by deployment of stem rust resistance (Sr) genes in wheat cultivars. However, a new stem rust race, TTKSK (known as Ug99 or TTKS) that emerged in eastern Africa, is a cause of concern because it has b...

Disease resistance is an extremely valuable control measure of rusts in cereal crops and is based, almost entirely, on simple procedures of identification and incorporation of major genes for resistance into economic varieties. Usually, several loci that carry these genes are known in each plant species. Frequently, several alleles at a locus can be distinguished on the basis of their reaction ...

can be easily identified and transferred into appropriate germplasm (Parlevliet, 1976). To date, 16 major raceLeaf rust caused by Puccinia hordei G. Otth is an important disease specific genes (designated as Rph1 to Rph16) for leaf of barley (Hordeum vulgare L.) in many regions of the world. Yield losses up to 32% have been reported in susceptible cultivars. The rust resistance have been identi...

(McIntosh and Gyarfas 1971, Gill et al. 1983, Tomar et al. 1988, Brown-Guedira et al. 1996). Cultivated T. timopheevii has been used for wheat improvement to a greater extent than has its wild progenitor, T. araraticum. Because T. timopheevii is a cultivated species, the chances of recovering agronomically acceptable derivatives from crosses with wheat are greater. However, T. timopheevii is en...

*Mention of trade names or commercial products in this publication is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the U.S. Department of Agriculture. USDA is an equal opportunity provider and employer. ABSTRACT Rust, caused by Hemileia vastatrix, is the main disease that decreases coffee production in Brazil. New and enhanced meth...