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Abstract Background Fusarium head blight (FHB) resistance in the durum wheat breeding gene pool is rarely reported. Triticum turgidum ssp. carthlicum line Blackbird is a tetraploid relative of durum wheat that offers partial FHB resistance. Resistance QTL were identified for the durum wheat cv. Strongfield × Blackbird population on chromosomes 1A, 2A, 2B, 3A, 6A, 6B and 7B in a previous study. The objective of this study was to identify the defense mechanisms underlying the resistance of Blackbird and report candidate regulator defense genes and single nucleotide polymorphism (SNP) markers within these genes for high-resolution mapping of resistance QTL reported for the durum wheat cv. Strongfield/Blackbird population. Results Gene network analysis identified five networks significantly (P

Ascochyta blight of lentil is an important fungal disease in many lentil-producing regions of the world causing major yield and grain quality losses. Quick shifts in aggressiveness of the population of the causal agent Ascochyta lentis mandates developing germplasm with novel and durable resistance. In the absence of complete resistance, lentil genotypes CDC Robin and 964a-46 have frequently been used as sources of partial resistance to ascochyta blight and carry non-allelic ascochyta blight resistance genes. RNA-seq analysis was conducted to identify differences in the transcriptome of CDC Robin, 964a-46 and the susceptible check Eston after inoculation with A. lentis. Candidate defense genes differentially expressed among the genotypes had hypothetical functions in various layers of plant defense, including pathogen recognition, phytohormone signaling pathways and downstream defense responses. CDC Robin and 964a-46 activated cell surface receptors (e.g. receptor like kinases) tentatively associated with pathogen-associated molecular patterns (PAMP) recognition and nucleotide-binding site leucine-rich repeat (NBS-LRR) receptors associated with intracellular effector recognition upon A. lentis infection, and differed in their activation of salicylic acid, abscisic acid and jasmonic acid / ethylene signal transduction pathways. These differences were reflected in the differential expression of downstream defense responses such as pathogenesis-related proteins, and genes associated with the induction of cell death and cell-wall reinforcement. A significant correlation between expression levels of a selection of genes based on quantitative real-time PCR and their expression levels estimated through RNA-seq demonstrated the technical and analytical accuracy of RNA-seq for identification of genes differentially expressed among genotypes. The presence of different resistance mechanisms in 964a-46 and CDC Robin indicates their value for pyramiding gene leading to more durable resistance to ascochyta blight.

Breeding for Fusarium head blight (FHB) resistance in durum wheat is complicated by the quantitative trait expression and narrow genetic diversity of available resources. High-density mapping of the FHB resistance quantitative trait loci (QTL), evaluation of their co-localization with plant height and maturity QTL and the interaction among the identified QTL are the objectives of this study. Two doubled haploid (DH) populations, one developed from crosses between Triticum turgidum ssp. durum lines DT707 and DT696 and the other between T. turgidum ssp. durum cv. Strongfield and T. turgidum ssp. carthlicum cv. Blackbird were genotyped using the 90K Infinium iSelect chip and evaluated phenotypically at multiple field FHB nurseries over years. A moderate broad-sense heritability indicated a genotype-by-environment interaction for the expression of FHB resistance in both populations. Resistance QTL were identified for the DT707 × DT696 population on chromosomes 1B, 2B, 5A (two loci) and 7A and for the Strongfield × Blackbird population on chromosomes 1A, 2A, 2B, 3A, 6A, 6B and 7B with the QTL on chromosome 1A and those on chromosome 5A being more consistently expressed over environments. FHB resistance co-located with plant height and maturity QTL on chromosome 5A and with a maturity QTL on chromosome 7A for the DT707 × DT696 population. Resistance also co-located with plant height QTL on chromosomes 2A and 3A and with maturity QTL on chromosomes 1A and 7B for the Strongfield × Blackbird population. Additive × additive interactions were identified, for example between the two FHB resistance QTL on chromosome 5A for the DT707 × DT696 population and the FHB resistance QTL on chromosomes 1A and 7B for the Strongfield × Blackbird population. Application of the Single Nucleotide Polymorphic (SNP) markers associated with FHB resistance QTL identified in this study will accelerate combining genes from the two populations.

Ascochyta blight of lentil is a prevalent disease in many lentil producing regions and can cause major yield and grain quality losses. The most environmentally acceptable and economically profitable method of control is to develop varieties with high levels of durable resistance. Genetic studies to date suggest that ascochyta blight resistance genes (R-gene) in lentil lines CDC Robin, ILL 7537, 964a-46, and ILL 1704 are non-allelic. To understand how different R-genes manifest resistance in these genotypes and an accession of Lens ervoides, L-01-827A, with high level of resistance to ascochyta blight, cellular and molecular defense responses were compared after inoculation with the causal pathogen Ascochyta lentis. Pathogenicity testing of the resistant lines to A. lentis inoculation revealed significantly lower disease severity on CDC Robin and ILL 7537 compared to ILL 1704 and 964a-46, and no symptoms of disease were observed on L-01-827A. Histological examinations indicated that cell death triggered by the pathogen might be disrupted as a mechanism of resistance in CDC Robin. In contrast, limiting colonization of epidermal cells by A. lentis is a suggested mechanism of resistance in 964a-46. A time-series comparison of the expressions of hallmark genes in salicylic acid (SA) and jasmonic acid (JA) signal transduction pathways between CDC Robin and 964a-46 was conducted. These partially resistant genotypes differed in the timing and the magnitude of SA and JA signaling pathway activation. The SA signaling pathway was only triggered in 964a-46, whereas the JA pathway was triggered in both partially resistant genotypes CDC Robin and 964a-46. The expression of JA-associated genes was lower in 964a-46 than CDC Robin. These observations corroborate the existence of diverse ascochyta blight resistance mechanisms in lentil genotypes carrying different R-genes.

The aim of this study was to verify that wheat seedlings treated with Pseudomonas fluorescens CHA0 (CHA0 hereafter) before inoculation with Gaeumannomyces graminis var. tritici (Ggt), a pathogen of take-all, acquire induced resistance to Ggt. The soil with wheat seedlings growing on it was drenched with a suspension of CHA0 cells and inoculated with Ggt 24 h later. Then, the seedlings were grown in a glasshouse, and severity of take-all disease, fresh weights of root and shoot and lengths of root and shoot, and also the activities of soluble peroxidase (SPOX), ionically cell-wall-bound peroxidase (CWPOX), β-1,3-glucanase, β-1,4-glucanase and the concentration of total phenolic compounds in the root of the seedlings were examined. The results indicated that the treatment with CHA0 before inoculation with Ggt mitigated the disease severity significantly, and increased the root and shoot lengths and root and shoot fresh weights. The treatment with CHA0 increased the activities of SPOX, CWPOX, β-1-3-glucanase, β-1,4-glucanase and phenolic compounds in the wheat roots and the activities of SPOX and β-1,4-glucansee activities were highest at day 4 and those of CWPOX and β-1,3-glucanase at day 6 after inoculation with Ggt. The concentration of total phenolic compounds was also highest at day 6 after the inoculation with Ggt. The results suggest that the take-all suppressing effect of CHA0 may be related to enhanced defense response of the wheat roots.

Introduction: Development of new technologies including multimedia in teaching has revolutionized the educational process. The purpose of this study was to evaluate the effects of multimedia education on learning and retention in the physiology course for the students of anesthesiology at Hamadan University of Medical Sciences.Materials and Methods: In this study, the pretest-posttest design with a control group was used. The population of this study consisted of all students of Anesthesiology at Hamadan University of Medical Sciences, who were selected using convenience sampling method. The total sample size included 57 students in two classes of 29 and 28 students. The instruments used in this study were a pre-test with the reliability of 0.90, a post-test with the reliability of 0.88, a self-made retention test with the reliability of 0.88, and a self-made multi-media course with the reliability of 0.83. The face and content validity of all these instruments were approved by the experts. The independent T-test and the Levine test were used to analyze the collected data.Results: The findings showed that: 1) the students undergoing multimedia teaching were superior to those with traditional methods (Levin test = 0.968 and p < 0.001) 2) the retention rate of students who have been trained through multimedia techniques was higher than that of the students who underwent traditional methods (Levin test = 0.429 and p < 0.001).Conclusion: Due to the impact of multimedia on learning and retention of the students, it seems that this method is useful in medical universities