The allohexaploid bread wheat originally derived from three closely related species with A, B and D genome. Although numerous studies were performed to elucidate its origin and phylogeny, no consensus conclusion has reached. In this study, we cloned and sequenced the genes Wcor15-2A, Wcor15-2B and Wcor15-2D in 23 diploid, 10 tetraploid and 106 hexaploid wheat varieties and analyzed their molecu...

Expression of resistance to Meloidogyne incognita and M. javanica from Aegilops squarrosa was studied in a synthetic allohexaploid produced from Triticum turgidum var. durum cv. Produra and Ae. squarrosa G 3489. The reproductive rate of different races of M. incognita and M. javanica, expressed in eggs per gram of fresh root, was low (P < 0.05) on the synthetic allohexaploid and the resistant p...

The complex process of allopolyploid speciation includes various mechanisms ranging from species crosses and hybrid genome doubling to genome alterations and the establishment of new allopolyploids as persisting natural entities. Currently, little is known about the genetic mechanisms that underlie hybrid genome doubling, despite the fact that natural allopolyploid formation is highly dependent...

Plant regeneration studies in cereals have been undertaken in immature embryos, scutellum and also in immature inflorescence tissue. The wheat mature embryos can also be employed for callusing and regeneration, as they are available throughout the year and have presently been employed for transformation studies. An efficient and reproducible method for Agrobacterium-mediated transformation of m...

The effect of neighbouring plants on crop root system architecture may directly interfere with water and nutrient acquisition, yet this important and interesting aspect of competition remains poorly understood. Here, the effect of the weed blackgrass (Alopecurus myosuroides Huds.) on wheat (Triticum aestivum L.) roots was tested, since a low density of this species (25 plants m-2) can lead to a...

This article comprises our final remarks on the phenotypic effects of alien plasmons on common wheat. Twenty-one vegetative, reproductive, and seed characters of 551 alloplasmic lines of 12 common wheat genotypes with 46 alloplasmons, and as the control, their euplasmic lines were investigated. Effects of genotype, plasmon, and their interaction had high statistical significance for all the cha...

For 17 cultivars of winter wheat (Triticum aestivum L.) different vernalisation and photoperiod responses were detected. The effect of photoperiod sensitivity was not significantly changed by vernalisation; different vernalisation responses were probably due to the presence of multiple alleles at Vrn loci. The delay in heading depended on the vernalisation deficit exponentially: y = parameter (...

Occurence and Yield Effects of Wheat Infected with Triticum Mosaic Virus Authors: D.L. Seifers, J.T. Martin, J.P. Fellers Submitted to: Plant Disease Triticum mosaic virus (TriMV) was discovered recently and little is known about the virus’ biology and potential to cause yield reductions. TriMV has been found all across the Great Plains and this study examined whether TriMV infection would re-o...

A dosage effect of chromosome 5A (formerly IX) of common wheat, Triticum aestivum L. emend Thell. ssp. vulgare, has been well established. With increasing dosage from monosomic to tetrasomic, the phenotype changes from speltoid to normal vulgare type (squarehead) to subcompactoid to compactoid (HUSKINS 1946; SEARS 1952, 1954) (Figure 1 and Table 3) . This is due to the pleiotropic gene Q locate...