A mitochondrial (mt) transcriptional unit, nad3-orf156, was studied in the nucleus-cytoplasm hybrids of wheat with D/D2 plasmons from Aegilops species and their parental lines. A comparative RFLP analysis and sequencing of the random PCR clones revealed the presence of seven sequence types and their polymorphic sites were mapped. All the hybrids possessed the paternal copies besides the materna...

The wheat Tsn1 gene on chromosome 5B confers sensitivity to a host-selective toxin produced by the pathogens that cause tan spot and Stagonospora nodorum blotch (SNB) known as Ptr ToxA and SnToxA, respectively (hereafter referred to as ToxA). A compatible Tsn1-ToxA interaction is known to play a major role in conferring susceptibility of hexaploid (common) wheat to SNB. However, a recent study ...

Towards the end of World War II, McFadden & Sears (1946) published a lengthy and classic paper on the origin of hexaploid or bread wheat. In the appendix to this paper they acknowledged that Kihara (1944) had also independently identified Aegilops tauschii (syn. Ae. squarrosa, Tritcum tauschii) as the D-genome donor of bread wheat. Since then, there have been many studies on the taxonomy, biolo...

The origin of modern wheats involved alloploidization among related genomes. To determine if Aegilops speltoides was the donor of the B and G genomes in AABB and AAGG tetraploids, we used a 3-tiered approach. Using 70 amplified fragment length polymorphism (AFLP) loci, we sampled molecular diversity among 480 wheat lines from their natural habitats encompassing all S genome Aegilops, the putati...

rRNA genes consist of long tandem repeats clustered on chromosomes, and their products are important functional components of the ribosome. In common wheat (Triticum aestivum), rDNA loci from the A and D genomes were largely lost during the evolutionary process. This biased DNA elimination may be related to asymmetric transcription and epigenetic modifications caused by the polyploid formation....

The cytosolic isoform of plant acetyl-CoA carboxylase is a multidomain enzyme involved in the synthesis of very-long-chain fatty acids and in secondary metabolism. Chromosome mapping of wheat identified one locus containing cytosolic acetyl-CoA carboxylase genes (Acc-2) and a related partially processed pseudogene (Psi-Acc-2) in the distal region of the long arm of wheat homoeologous group 3 ch...

Hexaploid triticale is an important forage crop and a promising energy plant. Some forms were previously reported for developing the hexaploid triticale, such as crossing tetraploid wheat or hexaploid wheat with rye, crossing hexaploid triticale and/or hexaploid wheat with octoploid triticale, and spontaneously appearing in the selfed progenies of octoploid triticale. In the present study, we d...

The process of domestication has led to dramatic morphological and physiological changes in crop species due to adaptation to cultivation and to the needs of farmers. To investigate the phenotypic architecture of shoot- and root-related traits and quantify the impact of primary and secondary domestication, we examined a collection of 36 wheat genotypes under optimal and nitrogen-starvation cond...

Abstract Italian ryegrass [ Lolium perenne L. spp. multiflorum (Lam.) Husnot] is one of the most troublesome weeds worldwide. also a grass seed crop cultivated on 50,000 ha in Oregon, where both diploid and tetraploid cultivars are grown. For this work, we will refer to species as multiflorum, since common names annual same species. A survey was conducted understand distribution frequency its s...