Authors:B. Hoffmann, N. Aranyi, and M. Molnár-Láng
The safety of wheat production in Hungary requires the propagation of droughttolerant cultivars because of the regular occurrence of water deficiency. Hybridization between related species makes it possible to transfer desirable traits from one species to another. Introgression lines developed from wheat/barley hybrids were investigated together with the parental wheat and barley cultivars to determine how the added barley chromosome (segment) influences drought tolerance in wheat. The plants were grown in the field at the UP Georgikon Faculty, Keszthely. Sowing and harvest were done by hand. Half the length of the 12 m rows was covered with a plastic rain shelter on 2
April (EC: 30–31) to protect the plants from rain, resulting in a 163 mm difference in water supplies between the control (not covered) and stressed (covered) treatments. Data were obtained for anthesis and maturity date, plant height, root/shoot ratio, leaf water potential, grain yield and grain yield components. The plants adapted to water deficiency by increasing the root/shoot ratio and decreasing the water potential and the duration of grain filling. The grain yield was reduced by 12%, averaged over the genotypes, mainly due to a decrease in the number of spikes per plant.
Authors:N.V. Trubacheeva, E.D. Badaeva, T.S. Osadchaya, and L.A. Pershina
Wild barley, Hordeum marinum subsp. gussoneanum (2n = 28) is a valuable source of genes that determine resistance to abiotic stresses. These resistance traits might be transferred to wheat due to the crossability of wild barley with bread wheat. The availability of reliable and rapid methods for the identification of H. marinum subsp. gussoneanum chromatin in a wheat background would facilitate the development of introgression wheat genotypes. For this purpose, we evaluated the applicability of eighty-seven H. vulgare EST markers for studying bread wheat – H. marinum subsp. gussoneanum substitution and addition lines. Of all of the markers studied, forty-three (49%) were amplified in H. marinum ssp. gussoneanum and wheat introgression lines. The identification of wild barley chromosomes using EST markers confirmed the GISH and C-banding data. Thus, it was established that the H. vulgare EST markers can be successfully used to identify the chromosomes of the H. marinum subsp. gussoneanum in introgression lines of wheat.
Authors:J. Alvarez, L. Caballero, S. Nadal, M. Ramírez, and A. Martín
has been identified as donor of
genome in the polyploid wheats. An amphiploid derived from the cross between one accession of
, carrying 1Ax + Ay high-molecular-weight glutenin subunits, and durum wheat cv.
has been synthesised and used as a bridge species to transfer genetic material from the wild to the cultivated wheat. Some quality traits were evaluated in twenty durum lines derived from this amphiploid after backcrossing to durum. All lines were selected for the presence of 1Ax + Ay but maintaining two different patterns for the low-molecular-weight glutenin subunits and grain colour. The lines with red grain showed higher pigment content than those with yellow grain. In addition, the former lines present higher gluten strength than the latter ones.
Authors:S. Sintayehu, A. Adugna, M. Fetene, A. Tirfessa, and K. Ayalew
This experiment was carried out to evaluate the growth, physiological and yield traits of stay-green (Stg) QTL introgression sorghum lines, which were developed by the Ethiopian Institute of Agricultural Research in collaboration with ICRISAT between 2006 and 2008, under induced post-flowering drought stress. It involved a total of 12 genotypes including seven Stg QTL introgression lines, two Stg donor parents and three senescent recurrent parents. It was organized in a split plot design with three replications under well-watered and induced drought stress growing conditions at Melka Werer, Ethiopia during the post-rainy season of 2014. Analysis of variance revealed that the effect of moisture regimes on all measured traits was significant (P > 0.05). Differences among the genotypes and genotypeby- water regime interaction were also significant (P > 0.05) for all the traits considered. Postflowering drought stress was observed to significantly reduce most of the growth, physiological and yield related traits. The Stg introgression lines Meko/B35-selection 120, Teshale/B35-selection 2 and Teshale/E36-1 showed better drought stress tolerance properties than the rest of the genotypes based on the measured growth and physiological traits. These introgression lines also showed better grain yield than their recurrent parents under post-flowering drought stress and can be used as new versions of the existing varieties (served as recurrent parents) and for future breeding programs. Furthermore, leaf chlorophyll content, assimilation rate, transpiration rate, water use efficiency, root length and root dry weight were found to have strong correlation and can be used to screen genotypes for post-flowering drought tolerance.
Authors:É. Szakács, K. Kruppa, I. Molnár, and M. Molnár-Láng
The aim of the present study was to test the efficiency of gamma irradiation in inducing translocations between wheat and barley genomes using addition lines. The Martonvásári 9 kr1-Igri disomic addition set, previously produced in Martonvásár, was irradiated with gamma rays. The pattern of irradiation-induced intergenomic chromosome rearrangements was analysed in the mutagenized (M0) generation by genomic
hybridization (GISH). Centric fusions and a wide variety of reciprocal, terminal and interstitial translocations were frequently induced. The intergeneric translocations produced here are expected to be stabilized in later backcross progenies as a set of introgression lines carrying few but distinct rearrangements.
Authors:C. Liu, Z. Yang, J. Jia, G. Li, J. Zhou, and Z. Ren
Knowledge of the chromosomal distribution of long terminal repeats (LTR) is important for understanding plant chromosome structure, genomic organization and evolution, as well as providing chromosomal landmarks that are useful for chromosome engineering. The aim of this study is to investigate the genomic distribution of
-like LTR pDbH12, which was first isolated from
species in relation to the genomic evolution and chromosome identification. Fluorescence
hybridization (FISH) analysis showed that pDbH12 is present on
(V genome) and
(H genome) species with the hybridized signals covering the entire chromosomes. However, clone pDbH12 did not hybridize to the genomes of
Secale, Triticum, Lophopyrum, Pseduoroengeria, Aegilops, Agropyron desertorum
Elymus. Thinopyrum intermedium
displayed fourteen chromosomes that hybridized with pDbH12. Sequential FISH identified these chromosomes as belonging to the J
genome. Results from sequence characterized amplified region (SCAR) marker and dot blot both support the FISH results, and the integrative results suggest that amplification of
-like LTR retrotransposons is an important factor which involved in the speciation process. Clone pDbH12 could serve as a cytogenetic marker for tracing chromatin from V or V
, H and J
genomes in wheat-alien introgression lines.
Authors:I.N. Leonova, A.I. Stasyuk, E.S. Skolotneva, and E.A. Salina
Cultivation of winter wheat varieties in the West Siberian region of Russia has competitive advantages compared to spring varieties: utilization of spring-summer moisture, early maturation and harvest and a high yield potential. The poor resistance of winter varieties to foliar diseases results in significant yield losses and facilitates the spread of pathogens to the spring wheat cultivars. The present study was conducted to evaluate the effectiveness of molecular markers specific for VRN-1 and Lr loci in selecting winter wheat genotypes resistant to leaf rust. The winter wheat cultivars Biyskaya ozymaya and Filatovka were crossed with spring wheat introgression lines 21-4 and 5366-180 and the spring wheat cultivar Tulaikovskaya 10 carrying LrTt2, LrAsp5 and Lr6Ai#2 loci from Triticum timopheevii, Aegilops speltoides and Thynopyrum intermedium, respectively. To identify winter wheat plants homozygous for target loci, F2 populations were screened with functional markers to VRN-1 genes and with markers specific for alien genetic material. Based on the genotyping analysis of 371 F2 plants a total of 44 homozygous genotypes with winter habit was identified. There were eight genotypes containing Lr loci among them. Evaluation of F2-derived F3-4 families for both seedling and adult resistance showed that only one F3-4 family had moderate susceptible reaction type to the field population of leaf rust. Others ranged from nearly immune to resistant with severity of 5%. The data also indicated the utility of the VRN-1 allele-specific markers for detection of genotypes with winter habit without vernalization at early stages of plant breeding.