The rust resistance genes Lr53 and Yr35, transferred to common wheat from Triticum dicoccoides, were reported previously to be completely linked on chromosome 6B. Four F (3) families were produced from a cross between a line carrying Lr53 and Yr35 (98M71) and the leaf rust and stripe rust susceptible genotype Avocet "S" and were rust tested using Puccinina triticina pathotype 53-1,(6),(7),10,11 and Puccinia striiformis f. sp. tritici pathotype 110 E143 A+. The homozygous resistant lines produced infection types of ";1-" and ";N" to these pathotypes, respectively. The Chi-squared tests indicated goodness-of-fit of the data for one leaf rust gene and one stripe rust gene segregation. Linkage analysis using this population demonstrated recombination of 3% between the genes. Microsatellite markers located on the short arm of chromosome 6B were used to map the genes, with the markers cfd1 and gwm508 being mapped approximately 1.1 and 4.5 cM, respectively, proximal to Lr53. Additional studies of the relationship between Lr36, also located on the short arm of chromosome 6B, and Lr53 indicated that the two genes were independent.

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Genotype × environment interaction (GEI) is an important aspect of both plant breeding and the successful introduction of new cultivars. In the present study, additive main effects and multiplicative interactions (AMMI) and genotype (G) main effects and genotype (G) × environment (E) interaction (GGE) biplot analyses were used to identify stable genotypes and to dissect GEI in Plantago. In total, 10 managed field trials were considered as environments to analyze GEI in thirty genotypes belonging to eight Plantago species. Genotypes were evaluated in a drought stress treatment and in normal irrigation conditions at two locations in Shiraz (Bajgah) for three years (2013-2014- 2015) and Kooshkak (Marvdasht, Fars, Iran) for two years (2014–2015). Three traits, seed yield and mucilage yield and content, were measured at each experimental site and in natural Plantago habitats. AMMI2 biplot analyses identified genotypes from several species with higher stability for seed yield and other genotypes with stable mucilage content and yield. P. lanceolata (G26), P. officinalis (G10), P. ovata (G14), P. ampleexcaulis (G11) and P. major (G4) had higher stability for seed yield. For mucilage yield, G21, G18 and G20 (P. psyllium), G1, G2 and G4 (P. major), G9 and G10 (P. officinalis) and P. lanceolata were identified as stable. G13 (P. ovata), G5 and G6 (P. major) and G30 (P. lagopus) had higher stability for mucilage content. No one genotype was found to have high levels of stability for more than one trait but some species had more than one genotype exhibiting stable trait performance. Based on trait variation, GGE biplot analysis identified two representative environments, one for seed yield and one for mucilage yield and content, with good discriminating ability. The identification of stable genotypes and representative environments should assist the breeding of new Plantago cultivars.

The wheat leaf rust fungus, Puccinia triticina, has widespread geographical distribution in Iran within the Fertile Crescent region of the Middle East where wheat was domesticated and P. triticina originated. Therefore, it is of great importance to identify the prevalence and distribution of P. triticina pathotypes in this area. From 2010 to 2017, 241 single-uredinium isolates of P. triticina were purified from 175 collections of P. triticina made from various hosts in 14 provinces of Iran, and they were tested on 20 Thatcher near-isogenic lines carrying single-leaf rust resistance genes. In total, 86 pathotypes were identified, of which the pathotypes FDTTQ, FDKPQ, FDKTQ, and FDTNQ were most prevalent. No virulence for Lr2a was detected, whereas virulence for Lr1 was found only on bread wheat in a few provinces in 2016. Only isolates from durum wheat and wild barley were virulent to Lr28. Although virulence for Lr9, Lr20, and Lr26 was observed in some years, the virulence frequency for these genes was lower than that of the other Lr genes. P. triticina collections from host plants with different ploidy levels or genetically dissimilar backgrounds were grouped individually according to genetic distance. Based on these results, collections from barley, durum wheat, oat, triticale, and wild barley were different from those of bread wheat.

Drought stress limits crop production in the world. Therefore, employing high-yielding cultivars tolerant to drought is an effective approach to reduce its detrimental effects. To identify drought tolerant genotypes, 36 wheat genotypes were evaluated during the 2010-2011 and 2011-2012 growth seasons. A field experiment was conducted in a split plot design with two irrigation treatments (100% field capacity until harvest and no irrigation after anthesis) as main plots in three replications and genotypes as subplots. Grain yield, its components and drought tolerance indices were measured. Results showed a significant reduction in yield and its components under drought conditions. Grain yield had significant positive correlations with stress tolerance index (STI), mean productivity index (MP) and geometric mean productivity (GMP) while it was negatively correlated with stress susceptibility index (SSI) and tolerance index (TOL) under stress condition. These results indicated that superior genotypes could be selected based on high values of STI, MP and A c c e p t e d M a n u s c r i p t Downloaded by [University of Arizona] at 04:19 05 July 2014 GMP and low value of SSI. The results were validated by principal component analysis (PCA) as it showed genotypes with high PC1 and low PC2 were more desirable. Based on the results, genotypes number 8, 11, 17, 30, 34 and 35 were recognized as suitable for both conditions.

The 1BL/1RS wheat-rye translocations had been used in wheat breeding programs worldwide. The objective of this study was to determine the effect of the 1BL/1RS translocation in SeriM82 /Babax recombinant population. 167 lines of this population were assayed under well-irrigated, terminal drought, heat and a combination of heat and drought stress conditions in two years. 5S rDNA and Iag95 markers were used to differentiate genotypes with or without the1BL/1RS translocation. Presence of 1BL/1RS translocation reduced grain yield (YLD), grain per spike (GSP) and grain per m 2 (GM2). QTLs in 1 BL/1RS segments indicated increased thousand-grain weight (TGW), chlorophyll content, spikelet per spike (SPLS), spike compactness (SCOM) and awn length (AWL) but reduced YLD, GSP and GM2. The 1BL/1RS carrying lines' response varied between assayed environments. Plants of drought trials were more affected by 1BL/1RS compared to others. Differences in the effects of 1BL/1RS and QTLs suggest that gene expression at translocation loci is restricted to specific environmental conditions. In general, the 1BL/1RS translocation could not be a suitable source of genetic diversity for enhancing grain yield under heat and drought stresses.

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Micronutrients malnutrition causes global health problems specifically in less developed and developing countries. The object ives of this study were to investigate variations in micronutrients, bread making quality and their relationships with grain yield (GY) in wheat. Fifty landrace varieties and 10 commercial cultivars were grown in a RCBD with no micronutrient fertilizer. Zinc (Zn +2 ) and iron (Fe +2 ) contents as mg kg -1 dry weight, dry gluten (Glu), sodium do-decyl sulfate (SDS) volume, grain hardness (GH), zeleny sedimentation volume (ZSV), grain protein content (Gpc), hectoliter weight (HW) and agronomic traits were assayed. Iron and Zinc concentrations were measured using atomic absorption spectroscopy (Shimadzu AA-670). Landraces had higher Fe +2 (24.93 to 66.51), Zn +2 (18.68 to 38.66) and GY (6.2 to 11.8 g) compared with commercial cultivars. This indicates the fact that breeding for micronutrients and bio-fortification of wheat cultivars have been forgotten. Higher Gpc of commercial cultivars (11.8% to 15.1%) than landrace varieties (9.8% to 14.03%) and SDS data showed insufficient bread-making quality in landraces. The highest correlations among baking-quality traits and micronutrients were observed between Gpc and SDS volume (r=0.82**) and grain Fe +2 (0.55**) and Zn +2 (0.52**) concentrations with Gpc. These were followed by correlations between grain Fe +2 and Zn +2 concentrations (0.51**) and between dry gluten content and SDS volume (0.30**). In conclusion, results showed that the hybridization of genotypes for incorporation of higher micronutrient, grain yield and better bread making quality would be more efficient than surveying for single superior plants via direct selection.