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This study investigated the regulation of gene expression in root, leaf, and grain tissues of bread wheat (Triticum aestivum L.) in response to drought and heat stresses at the grain-filling stage for the first time by transcriptome analysis. The sequencing result, obtained on a Roche 454 GS FLX+, yielded a total of 117,790,028 base reads and 8,351 unigenes with an average length of 461 bp. Through transcriptome analysis, numerous transcripts have been identified to be involved in maintaining osmotic and ionic balance, detecting and transmitting signals, modifying protein structure and function, ensuring membrane integrity and stability, and are associated with energy and carbohydrate metabolism. Against drought and hightemperature stresses, tolerance mechanisms in the root, leaf, and grain tissues differentially regulated many specific transcription factors identified. Betaine aldehyde dehydrogenase, callose synthase, cell wall-associated hydrolase, MYB33, and NAC69 transcription factors expression levels were measured with qRT-PCR. Transcriptome analysis revealed that the transcripts identified were related to osmotic and ionic balance, signal detection and transduction, modification of structural and functional proteins, cell membrane structure and stability, energy and carbohydrate metabolism, and their expression level varied according to the tissue or drought and high-temperature stress applied. [ABSTRACT FROM AUTHOR]

The limited germplasm resources of hulless barley restrict the breeding of hulless barley with improved traits. Mutation techniques are an effective tool for generating variation for plant breeding studies. This study aimed to evaluate the impact of gamma-ray at different doses on certain seedling properties of M1 plants of two hulless barley genotypes, as well as determine the effective dose (ED50). The seeds of two hulless two-row barley genotypes, cv. Yalin and hulless barley line YAA7050-14, were irradiated with 100, 150, 200, 250, and 300 gray Gamma-rays delivered by a Cobalt 60 source along with non-irradiated control samples. Gamma-ray irradiation affects the seedling properties of M1 plants of both hulless barley genotypes significantly. The significant effect varied based on the doses, traits, and genotypes. While lower doses were found statistically identical to the control in the majority of qualities in the M1 generation, 250-300 gray gamma ray doses caused statistically significant decreases in the majority of characteristics studied in both genotypes. The effective doses (ED50) for hulless barley genotypes were determined by plotting growth reduction values of seedling lengths, then the polynomial regression equations were calculated for each genotype. It was determined that 50% growth reduction in shoot length was reached at 214.1 Gy and 253.4 Gy for cv. Yalin and line YAA7050-14, respectively. [ABSTRACT FROM AUTHOR]

Double haploids (DHs) production and utilization is an important aspect of wheat breeding programs in worldwide, because, it provides many advantages over the conventional breeding program. Therefore, in vitro and in vivo responses of anther derived two bread wheat cultivars and their F1 crosses were investigated. Results showed significant genetic variation among the tested bread wheat genotypes. The pre-cold treated anther derived embryonic calli and shoot induction (%) were obtained from all genotypes that ranged 44 - 76% and 32 - 58% respectively. The highest shoot induction from embryonic calli was achieved from F1 cross of Zubkov x Atay-85, whereas, lowest induction was obtained from Atay-85 cultivar. The F1 cross (Zubkov x Atay-85) showed a better response in anther culture in term of shoots per plant and root induction than their respective parental genotypes. The present results indicated positive and significant heterotic effects of F1 crosses for calli and shoot induction that also showed less albino plant regeneration after colchicine treatments. Total number of 114 anthers driven DHs lines from two genotypes and their F1 crosses were regenerated, confirmed by flow-cytometry and evaluated under field condition. Some DHs lines were found to be significantly superior for agronomical traits including seed yield than the parental genotypes as well as local bread wheat (control) cultivars. [ABSTRACT FROM AUTHOR]

Seedling stage reactions of thirty-eight 2-rowed barley landraces representing different areas of Turkey obtained from Osman Tosun Gene Bank to two Pyrenophora teres f. teres isolates were evaluated. In addition, barley cultivars Bülbül 89 and Avcı 2002 were included. Landraces exhibited different reactions to the disease and their reactions ranged from resistant-moderately resistant to susceptible. Landrace number 33 obtained from Diyarbakır was found the most resistant to the disease compared to all other landraces whereas landrace number 10 obtained from Bilecik-Söğüt, and cultivar Bülbül 89 were the most susceptible. The majority of the landraces were classified between the Moderately Resistant-Moderately Susceptible to Moderately Susceptible-Susceptible. Landrace number 33 exhibited Resistant-Moderately Resistant reactions to both isolates. This landrace from Diyarbakır could be used as the seed source and in the breeding studies for obtaining barley cultivars resistant to the net form of net blotch disease. [ABSTRACT FROM AUTHOR]