A single NLR gene confers resistance to leaf and stripe rust in wheat.

Nucleotide-binding leucine-rich repeat (NLR) disease resistance genes typically confer resistance against races of a single pathogen. Here, we report that Yr87/Lr85, an NLR gene from Aegilops sharonensis and Aegilops longissima, confers resistance against both P. striiformis tritici (Pst) and Puccinia triticina (Pt) that cause stripe and leaf rust, respectively.

36-year study reveals stability of a wild wheat population across microhabitats.

Long-term genetic studies of wild populations are very scarce, but are essential for connecting ecological and population genetics models, and for understanding the dynamics of biodiversity. We present a study of a wild wheat population sampled over a 36-year period at high spatial resolution. We genotyped 832 individuals from regular sampling along transects during the course of the experiment.

Virulence Survey of in Israel Revealed Considerable Changes in the Pathogen Population During the Period 2001 to 2019.

A total of 353 urediniospore isolates of f. sp. () collected in Israel during 2001 to 2019 were analyzed.

Reducing the size of an alien segment carrying leaf rust and stripe rust resistance in wheat.

Background: Leaf and stripe rusts are two major wheat diseases, causing significant yield losses. The preferred way for protecting wheat from rust pathogens is by introgression of rust resistance traits from wheat-related wild species. To avoid genetic drag due to replacement of large wheat chromosomal segments by the alien chromatin, it is necessary to shorten the alien chromosome segment in primary recombinants.

Functional Variation of Plant-Pathogen Interactions: New Concept and Methods for Virulence Data Analyses.

Classical virulence analysis is based on discovering virulence phenotypes of isolates with regard to a composition of resistance genes in a differential set of host genotypes. With such a vision, virulence phenotypes are usually treated in a genetic manner as one of two possible alleles, either virulence or avirulence in a binary locus. Therefore, population genetics metrics and methods have become prevailing tools for analyzing virulence data at multiple loci.

Resistance of Aegilops Species from Israel to Widely Virulent African and Israeli Races of the Wheat Stem Rust Pathogen.

Widely virulent races of the stem rust pathogen (Puccinia graminis f. sp. tritici) such as those isolated from Africa (e.

Linkage disequilibrium and association analysis of stripe rust resistance in wild emmer wheat (Triticum turgidum ssp. dicoccoides) population in Israel.

Rapid LD decay in wild emmer population from Israel allows high-resolution association mapping. Known and putative new stripe rust resistance genes were found. Genome-wide association mapping (GWAM) is becoming an important tool for the discovery and mapping of loci underlying trait variation in crops, but in the wild relatives of crops the use of GWAM has been limited.

Introgression of leaf rust and stripe rust resistance from Sharon goatgrass (Aegilops sharonensis Eig) into bread wheat (Triticum aestivum L.).

Leaf rust and stripe rust are devastating wheat diseases, causing significant yield losses in many regions of the world. The use of resistant varieties is the most efficient way to protect wheat crops from these diseases. Sharon goatgrass (Aegilops sharonensis or AES), which is a diploid wild relative of wheat, exhibits a high frequency of leaf and stripe rust resistance.

Genetic differentiation of Puccinia triticina populations in the Middle East and genetic similarity with populations in Central Asia.

Leaf rust of wheat, caused by Puccinia triticina, is a common and widespread disease in the Middle East. The objective of this study was to determine whether genetically differentiated groups of P. triticina are present in the Middle East region and to compare the population from the Middle East with the previously characterized population from Central Asia to determine whether genetically similar groups of isolates are found in the two regions.

Pathogen race determines the type of resistance response in the stripe rust-Triticum dicoccoides pathosystem.

Wild relatives of crop plants may serve as a promising source for screening for new disease resistance genes that can be utilized in breeding programs. Triticum dicoccoides, the wild progenitor of most cultivated wheats, was shown to harbor many resistance genes against the major diseases attacking cultivated wheat. Stripe rust is a devastating fungal disease that attacks wheat in many regions of the world.

Genome size in natural and synthetic autopolyploids and in a natural segmental allopolyploid of several Triticeae species.

Nuclear DNA amount (1C) was determined by flow cytometry in the autotetraploid cytotype of Hordeum bulbosum, in the cytologically diploidized autotetraploid cytotypes of Elymus elongatus, Hordeum murinum subsp. murinum and Hordeum murinum subsp. leporinum, in Hordeum marinum subsp.

Comparative Analysis of Indices in the Study of Virulence Diversity Between and Within Populations of Puccinia recondita f. sp. tritici in Israel.

ABSTRACT Isolates of Puccinia recondita f. sp. tritici (n = 260) obtained from bread, durum, and wild emmer wheat leaf collections throughout Israel during 1993 to 1997 were analyzed for virulence on a set of wheat differentials.

Virulence associations in oat crown rust.

ABSTRACT Isolates of Puccinia coronata obtained from natural populations of Avena sterilis in Israel, winter oat (A. sativa) cultivars in Texas, and spring oat cultivars in the Northern Plains states of Minnesota, North Dakota, and South Dakota were analyzed for significance of pairwise virulence associations. Isolates from all three regions were tested on 25 oat lines with single P.

Leaf Rust on Aegilops speltoides Caused by a New Forma Specialis of Puccinia triticina.

ABSTRACT A leaf rust attacking Aegilops speltoides in its natural habitat is reported for the first time. It was found in two locations in northern and central Israel. The two collections from A.

Patterns of Virulence in Natural Populations of Puccinia coronata on Wild Oat in Israel and in Agricultural Populations on Cultivated Oat in the United States.

ABSTRACT Crown rust (Puccinia coronata) in indigenous populations of Avena sterilis has been cited as an example of stability of wild pathosystems that consist of natural mixtures of resistance and virulence. This study confirmed that virulence/avirulence polymorphisms in P. coronata on A.

Genetic Variation and Virulence on Lr26 in Puccinia triticina.

ABSTRACT The genetic relationships between isolates of Puccinia triticina virulent on wheat with the Lr26 resistance gene were studied. The diversity within and between isolates of P. triticina from Israel, Europe, and the United States was determined by virulence on near-isogenic Thatcher lines and by random amplified polymorphic DNA.

Morphology, life cycle biology, and DNA sequence analysis of rust fungi on garlic and chives from california.

ABSTRACT In the late 1990s, commercial garlic fields in California (CA) were devastated by an outbreak of rust caused by Puccinia allii. We compared collections of the pathogen from garlic (Allium sativum) and chives (A. schoenoprasum) in central CA and Oregon (OR) to collections from garlic and leek (A.

Nuclear DNA amount and genome downsizing in natural and synthetic allopolyploids of the genera Aegilops and Triticum.

Recent molecular studies in the genera Aegilops and Triticum showed that allopolyploidization (interspecific or intergeneric hybridization followed by chromosome doubling) generated rapid elimination of low-copy or high-copy, non-coding and coding DNA sequences. The aims of this work were to determine the amount of nuclear DNA in allopolyploid species of the group and to see to what extent elimination of DNA sequences affected genome size. Nuclear DNA amount was determined by the flow cytometry method in 27 natural allopolyploid species (most of which were represented by several lines and each line by several plants) as well as 14 newly synthesized allopolyploids (each represented by several plants) and their parental plants.

Genome size and genome evolution in diploid Triticeae species.

One of the intriguing issues concerning the dynamics of plant genomes is the occurrence of intraspecific variation in nuclear DNA amount. The aim of this work was to assess the ranges of intraspecific, interspecific, and intergeneric variation in nuclear DNA content of diploid species of the tribe Triticeae (Poaceae) and to examine the relation between life form or habitat and genome size. Altogether, 438 plants representing 272 lines that belong to 22 species were analyzed.

Resistance to Leaf Rust, Stripe Rust, and Stem Rust in Aegilops spp. in Israel.

In all, 1,323 single plant accessions of Aegilops bicornis, A. kotschyi, A. longissima, A.

Leaf Rust and Stem Rust Resistance in Triticum dicoccoides Populations in Israel.

A total of 742 single plant accessions of Triticum dicoccoides were collected from 26 locations in Israel. All accessions were evaluated for leaf rust (Puccinia triticina) resistance in field plots at Tel Aviv, and subsets of 284 and 468 accessions were tested in the greenhouse in Tel Aviv and St. Paul, MN, respectively, for seedling resistance to leaf rust; 460 accessions were also tested for seedling resistance to stem rust (Puccinia graminis f.

Self-fertility and other distinguishing characteristics of a new morphotype of Puccinia coronata pathogenic on smooth brome grass.

A new morphotype of Puccinia coronata, pathogenic to Bromus inermis, a common roadside and pasture grass in the northern United States, was discovered in the 1990s and described as P. coronata f. sp.