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The authors use 2014–2018 data from the American Community Survey to answer two questions: To what extent is military service associated with higher rates of earning a bachelor’s degree in a science, technology, engineering, and mathematics (STEM) field (vs. a non-STEM field)? To what extent is this relationship gendered? The findings suggest that military service is associated with higher odds of completing a STEM degree and that this association is particularly strong for female veterans. Comparison across multiple STEM definitions suggests that military service does not simply channel women into traditionally female-dominated STEM fields. Instead, the findings show the biggest boost for women earning degrees in traditionally male-dominated STEM fields. The authors situate these findings in light of extant empirical and theoretical research on gender gaps in STEM and discuss implications for policy and research.

Background: Demographers typically ask about societal, not personal, fertility ideals. Societal ideals are probably more stable than personal ideals. Assessing whether personal fertility ideals are as stable as societal ideals could inform models of population fertility change and models of well-being associated with fertility outcomes. Methods: We use the two-wave National Survey of Fertility Barriers (NSFB) to model stability and change in fertility ideals among 879 women in heterosexual couples that persisted for both waves. Results: Personal fertility ideals are stable for most (69Š) women, but roughly one-third adjust their ideal number between waves. Of the women who changed their personal fertility ideal, approximately half increase and half decrease their personal fertility ideal over time. Multinomial logistic regression indicates that women with a higher fertility ideal at Wave 1 had higher odds of increasing and lower odds of decreasing their fertility ideal by Wave 2. Higher education was associated with lower likelihood of increasing fertility ideals. In addition, full-time employment at the initial interview was associated with higher likelihood of decreasing fertility ideals. Conclusions: Individual characteristics, attitudes, life course, and social cues are associated with changes in personal fertility ideals. More characteristics were associated with decreases than increases in personal fertility ideals. Contribution: By demonstrating that many women change personal fertility ideals over three years, the current study advances understanding of variations in fertility experiences. Importantly, these findings can also inform policies and interventions designed to support child and maternal health.

Plant pathogens pose a continuous threat to global food production. Recent discoveries in plant immunity research unveiled a unique protein family characterized by an unusual resistance protein structure that combines two kinase domains. This study demonstrates the widespread occurrence of tandem kinase proteins (TKPs) across the plant kingdom. An examination of 104 plant species' genomes uncovered 2,682 TKPs. The majority (95.6%) of these kinase domains are part of the receptor-like kinase-Pelle family, which is crucial for cell surface responses in plant immunity. Notably, 90% of TKPs comprise dual kinase domains, with over 50% being pseudokinases. Over 56% of these proteins harbor 127 different integrated domains, and over 47% include a transmembrane domain. TKP pseudokinases and/or integrated domains probably serve as decoys, engaging with pathogen effectors to trigger plant immunity. The TKP Atlas we created sheds light on the mechanisms of TKP convergent molecular evolution and potential function., Competing Interests: Competing interests: The authors declare no competing interests., (© 2025. The Author(s), under exclusive licence to Springer Nature America, Inc.)

Nucleotide-binding leucine-rich repeat (NLR) disease resistance genes typically confer resistance against races of a single pathogen. Here, we report that Yr87/Lr85, an NLR gene from Aegilops sharonensis and Aegilops longissima, confers resistance against both P. striiformis tritici (Pst) and Puccinia triticina (Pt) that cause stripe and leaf rust, respectively. Yr87/Lr85 confers resistance against Pst and Pt in wheat introgression as well as transgenic lines. Comparative analysis of Yr87/Lr85 and the cloned Triticeae NLR disease resistance genes shows that Yr87/Lr85 contains two distinct LRR domains and that the gene is only found in Ae. sharonensis and Ae. longissima. Allele mining and phylogenetic analysis indicate multiple events of Yr87/Lr85 gene flow between the two species and presence/absence variation explaining the majority of resistance to wheat leaf rust in both species. The confinement of Yr87/Lr85 to Ae. sharonensis and Ae. longissima and the resistance in wheat against Pst and Pt highlight the potential of these species as valuable sources of disease resistance genes for wheat improvement., Competing Interests: Competing interests The authors declare the following competing interests: D.S., R.A., R.K, E.M., A.M-D., and A.S. are inventors on the US patent application 63/250,413 filed by Ramot (Tel Aviv University) and relating to the use of Yr87/Lr85 for leaf and stripe rust resistance in transgenic wheat. All other authors claim no competing interests., (© 2024. The Author(s).)

Long-term genetic studies of wild populations are very scarce, but are essential for connecting ecological and population genetics models, and for understanding the dynamics of biodiversity. We present a study of a wild wheat population sampled over a 36-year period at high spatial resolution. We genotyped 832 individuals from regular sampling along transects during the course of the experiment. Genotypes were clustered into ecological microhabitats over scales of tens of metres, and this clustering was remarkably stable over the 36 generations of the study. Simulations show that it is difficult to determine whether this spatial and temporal stability reflects extremely limited dispersal or fine-scale local adaptation to ecological parameters. Using a common-garden experiment, we showed that the genotypes found in distinct microhabitats differ phenotypically. Our results provide a rare insight into the population genetics of a natural population over a long monitoring period., (© 2024 The Author(s). Molecular Ecology published by John Wiley & Sons Ltd.)

Interspecific hybridization increases genetic diversity, which is essential for coping with changing environments. Hybrid zones, occurring naturally in overlapping habitats of closely related species, can be artificially established during afforestation. The resulting interspecific hybridization may promote sustainability in artificial forests, particularly in regions facing degradation due to climate change. Currently, there is limited evidence of hybridization during regeneration of artificial forests. Here, we studied the frequency of Pinus brutia Ten. × P. halepensis Mill. hybridization in five planted forests in Israel in three stages of forest regeneration: seeds before dispersal, emerged seedlings and recruited seedlings at the end of the dry season. We found hybrids on P. brutia, but not on P. halepensis trees due to asynchronous cone production phenology. Using 94 single-nucleotide polymorphism (SNP) markers, we found hybrids at all stages, most of which were hybrids of advanced generations. The hybrid proportions increased from 4.7 ± 2.1 to 8.2 ± 1.4 and 21.6 ± 6.4 per cent, from seeds to emerged seedlings and to recruited seedlings stages, respectively. The increased hybrid ratio implies an advantage of hybrids over P. brutia during forest regeneration. To test this hypothesis, we measured seedling growth rate and morphological traits under controlled conditions and found that the hybrid seedlings exhibited selected traits of the two parental species, which likely contributed to the fitness and survival of the hybrids during the dry season. This study highlights the potential contribution of hybrids to sustainable-planted forests and contributes to the understanding of genetic changes that occur during the regeneration of artificial forests., (© 2024 The Author(s). Molecular Ecology published by John Wiley & Sons Ltd.)

Gene cloning in repeat-rich polyploid genomes remains challenging. Here, we describe a strategy for overcoming major bottlenecks in cloning of the powdery mildew resistance gene (R-gene) Pm69 derived from tetraploid wild emmer wheat. A conventional positional cloning approach was not effective owing to suppressed recombination. Chromosome sorting was compromised by insufficient purity. A Pm69 physical map, constructed by assembling Oxford Nanopore Technology (ONT) long-read genome sequences, revealed a rapidly evolving nucleotide-binding leucine-rich repeat (NLR) R-gene cluster with structural variations. A single candidate NLR was identified by anchoring RNA sequencing reads from susceptible mutants to ONT contigs and was validated by virus-induced gene silencing. Pm69 is likely a newly evolved NLR and was discovered in only one location across the wild emmer wheat distribution range in Israel. Pm69 was successfully introgressed into cultivated wheat, and a diagnostic molecular marker was used to accelerate its deployment and pyramiding with other R-genes., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

The rust diseases, including leaf rust caused by Puccinia triticina ( Pt ), stem rust caused by P. graminis f. sp. tritici ( Pgt ), and stripe rust caused by P. striiformis f. sp. tritici ( Pst ), are major limiting factors in wheat production worldwide. Identification of novel sources of rust resistance genes is key to developing cultivars resistant to rapidly evolving pathogen populations. Aegilops longissima is a diploid wild grass native to the Levant and closely related to the modern bread wheat D subgenome. To explore resistance genes in the species, we evaluated a large panel of Ae. longissima for resistance to several races of Pt , Pgt , and Pst , and conducted a genome-wide association study (GWAS) to map rust resistance loci in the species. A panel of 404 Ae. longissima accessions, mostly collected from Israel, were screened for seedling-stage resistance to four races of Pt , four races of Pgt , and three races of Pst . Out of the 404 accessions screened, two were found that were resistant to all 11 races of the three rust pathogens screened. The percentage of all accessions screened that were resistant to a given rust pathogen race ranged from 18.5% to 99.7%. Genotyping-by-sequencing (GBS) was performed on 381 accessions of the Ae. longissima panel, wherein 125,343 single nucleotide polymorphisms (SNPs) were obtained after alignment to the Ae. longissima reference genome assembly and quality control filtering. Genetic diversity analysis revealed the presence of two distinct subpopulations, which followed a geographic pattern of a northern and a southern subpopulation. Association mapping was performed in the genotyped portion of the collection (n = 381) and in each subpopulation (n = 204 and 174) independently via a single-locus mixed-linear model, and two multi-locus models, FarmCPU, and BLINK. A large number (195) of markers were significantly associated with resistance to at least one of 10 rust pathogen races evaluated, nine of which are key candidate markers for further investigation due to their detection via multiple models and/or their association with resistance to more than one pathogen race. The novel resistance loci identified will provide additional diversity available for use in wheat breeding., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Page, Huang, Ronen, Sela, Sharon, Shrestha, Poland and Steffenson.)

Objective: To determine the incidence, risk factors, and short-term maternal outcomes of women with pathologically confirmed retained products of conception (RPOC) following vaginal delivery., Methods: Prospective cohort study of women with suspicion of RPOC following vaginal delivery, from March 2018 to April 2019. Women were followed for eight weeks postpartum. Women with complete retained placenta were excluded. Women with pathologically confirmed RPOC were compared to those without. Univariate analysis was conducted (ORs; [95% CI]) and was followed by multivariate analysis (aOR; [95% CI])., Results: During the study period, there were 16,583 vaginal deliveries. A total of 96 women (0.58%) with a suspicion of RPOC were enrolled, of these, 53 women (55%) had pathologically confirmed RPOC. The most significant risk factors for pathologically confirmed RPOC were placental abruption (aOR 5.0 [2.29-11.13]) and Oxytocin augmentation of labor (aOR 1.7 [1.07-2.63]). Pathologically confirmed RPOC were associated with higher rates of prolonged hospitalization (OR 9.2 [2.83-30.05]), postpartum hemorrhage (PPH) (OR 6.6 [3.60-11.98]), hemoglobin drop > 3 g/dl (OR 11.4 [5.49-23.49]), and blood transfusion (OR 8.6 [2.07-38.18]). Women who had exploration of uterine cavity without pathological confirmation of RPOC, still had higher rates of perineal laceration (OR 17.6 [4.93-63.08]), PPH (OR 6.1 [3.05-12.21]), and a hemoglobin drop > 3 g/dl (OR 6.0 [2.13-16.95])., Conclusions: Pathologically confirmed RPOC following vaginal delivery has unique characteristics and is associated with significantly higher rates of PPH and blood transfusions. These findings may assist in the development of better criteria for selecting women for manual exploration and for preventive measures to reduce PPH and complications.

Purpose: To investigate a potential association between retinal layer thinning and pregnancy-related adverse outcomes., Methods: A prospective observational study included 32 pregnant women between the ages of 18 and 45. Seventeen had uneventful pregnancies, and 15 experienced an adverse obstetrical outcome. Macular swept-source ocular coherence tomography was performed, and selective layers of the retina were evaluated. Adverse obstetrical outcome was defined as any of the following: preterm delivery, preeclampsia, pregnancy-induced hypertension, elevated liver function tests, thrombocytopenia and need for magnesium., Results: The inner superior ganglion cell layer (GCL) was found to be thinner in the cohort with composite adverse obstetrical outcomes than in the cohort without complications (84.5±6.9 vs. 89.5±6.1μm respectively; P=0.04). Total inner superior (295.5±39.1 vs. 302.5±12.7μm; P=0.03) and inferior retinal thickness (289.0±13.9 vs. 301.0±17.1μm; P=0.03) as well as total macular volume (7.5±0.3 vs. 7.7±0.3 mm 3 ; P=0.02) were also lower in women with adverse obstetrical outcomes., Conclusion: Thinning of the macular ganglion cell layer was associated with adverse outcomes in pregnancy. Larger studies are necessary to assess the potential role of macular GCL analysis in pregnancy., (Copyright © 2022 Elsevier Masson SAS. All rights reserved.)

Background: Few studies have focused on the delivery subsequent to a failed vacuum delivery (failed-VD) in secundiparas. The objective of the current study was to examine the factors associated with a vaginal delivery following a failed-VD., Methods: An historical prospective cohort. Obstetric characteristics of secundiparas who underwent a planned caesarean delivery (CD) were compared to those who elected a trial of labour (TOLAC) at single medical-centre, throughout 2006-2019. The latter were further analysed to study for factures associated with successful vaginal birth (VBAC)., Results: Among the 115 secundiparas included, 89 (77%) underwent TOLAC. Compared to women who underwent an elective CD, those who underwent TOLAC were younger by a mean of 4 years, were more likely to have conceived spontaneously, and had a more advanced gestation by a mean of 10 days. VBAC was achieved in 62 women (70%). New-borns of women with VBAC had in average a lower birth weight compared to those with failed TOLAC, (-)195 g ± 396 g versus ( +)197 g ± 454 g respectively, P < 0.01. Having a higher neonatal birthweight at P2 by increments of 500 g, 400 g or 300 g was associated with a failed TOLAC; OR of 9.7 (95%CI; 2.3, 40.0), 11.5 (95%CI; 2.8, 46.7) and 4.5 (95%CI; 1.4, 13.9), respectively., Conclusions: Among secundiparas with a previous CD due to a failed-VD, the absolute difference of neonatal BW was found to be significantly associated with achieving VBAC., (© 2022. The Author(s).)

A total of 353 urediniospore isolates of Puccinia striiformis f. sp. tritici ( Pst ) collected in Israel during 2001 to 2019 were analyzed. Pst pathogenicity was studied with a set of 20 differentials (17 Avocet and 3 other lines). Three periods were compared: 2001 to 2007, 2009 to 2016, and 2017 to 2019. No virulence to Yr5 or Yr15 was detected. Virulence frequencies on Yr4 , Yr10 , Yr24 , and YrSp genes rose to the moderate level (0.28 to 0.44) in 2017 to 2019. Virulence frequencies to Yr2 and Yr9 decreased. One Pst phenotype was identified in all three periods, but its frequency drastically decreased from 0.74 in 2001 to 2016 to 0.21 in 2017 to 2019. The most probable scenario of emergence of wheat yellow rust in Israel is wind dissemination of Pst urediniospores from the Horn of Africa. Variability of the Pst population increased amid considerable evolution with two major transformations in 2009 and 2017. The first modification can be attributed to changes in wheat genetic background in Israel due to deployment of new cultivars resistant to yellow rust since 2004. The second shift in 2017 can be primarily explained by intensive deployment of wheat cultivars resistant to the stem rust race Ug99 in the 2010s in the Horn of Africa. This led to changing genetic backgrounds of the cultivated wheats in the donor region and development and long-distance spread of new Pst phenotypes to Israel. Two singular multivirulent Pst phenotypes were identified in 2019, one of them being closely related to the aggressive Warrior race. Such phenotypes may potentially defeat existing resistances.

The objectives of this study were to identify genetic loci in the bread wheat genome that would influence yield stability and quality under water stress, and to identify accessions that can be recommended for cultivation in dry and hot regions. We performed a genome-wide association study (GWAS) using a panel of 232 wheat accessions spanning diverse ecogeographic regions. Plants were evaluated in the Israeli Northern Negev, under two environments: water-limited (D; 250 mm) and well-watered (W; 450 mm) conditions; they were genotyped with ~71,500 SNPs derived from exome capture sequencing. Of the 14 phenotypic traits evaluated, 12 had significantly lower values under D compared to W conditions, while the values for two traits were higher under D. High heritability ( H 2 = 0.5-0.9) was observed for grain yield, spike weight, number of grains per spike, peduncle length, and plant height. Days to heading and grain yield could be partitioned based on accession origins. GWAS identified 154 marker-trait associations (MTAs) for yield and quality-related traits, 82 under D and 72 under W, and identified potential candidate genes. We identified 24 accessions showing high and/or stable yields under D conditions that can be recommended for cultivation in regions under the threat of global climate change., Competing Interests: The authors declare no conflicts of interest.

Aegilops is a close relative of wheat (Triticum spp.), and Aegilops species in the section Sitopsis represent a rich reservoir of genetic diversity for the improvement of wheat. To understand their diversity and advance their utilization, we produced whole-genome assemblies of Aegilops longissima and Aegilops speltoides. Whole-genome comparative analysis, along with the recently sequenced Aegilops sharonensis genome, showed that the Ae. longissima and Ae. sharonensis genomes are highly similar and are most closely related to the wheat D subgenome. By contrast, the Ae. speltoides genome is more closely related to the B subgenome. Haplotype block analysis supported the idea that Ae. speltoides genome is closest to the wheat B subgenome, and highlighted variable and similar genomic regions between the three Aegilops species and wheat. Genome-wide analysis of nucleotide-binding leucine-rich repeat (NLR) genes revealed species-specific and lineage-specific NLR genes and variants, demonstrating the potential of Aegilops genomes for wheat improvement., (© 2022 The Authors. The Plant Journal published by Society for Experimental Biology and John Wiley & Sons Ltd.)

Objective: To evaluate the impact of Covid-19 vaccination (Pfizer-BioNTech BNT162b2) during the third trimester of pregnancy on maternal and neonatal outcomes., Design: A multicentre, retrospective computerised database., Population: Women who gave birth at >24 weeks of gestation in Israel, between January and April 2021, with full records of Covid-19 disease and vaccination status., Methods: Women who received two doses of the vaccine were compared with unvaccinated women. Women who were recorded as having disease or a positive Covid-19 polymerase chain reaction (PCR) swab during pregnancy or delivery were excluded from both study groups. Univariate analysis was followed by multivariate logistic regression., Main Outcome Measures: Composite adverse maternal outcomes. Secondary outcomes were vaccination rate and composite adverse neonatal outcomes., Results: The overall uptake of one or both vaccines was 40.2%; 712 women who received two doses of the Covid-19 vaccine were compared with 1063 unvaccinated women. Maternal composite outcomes were comparable between the groups; however, women who received the vaccine had higher rates of elective caesarean deliveries (CDs) and lower rates of vacuum deliveries. An adjusted multivariable logistic regression analysis demonstrated that Covid-19 vaccination was not associated with maternal composite adverse outcome (aOR 0.8, 95% CI 0.61-1.03); a significant reduction in the risk for neonatal composite adverse outcomes was observed (aOR 0.5, 95% CI 0.36-0.74)., Conclusions: In a motivated population covered by a National Health Insurance Plan, we found a 40.2% rate of vaccination for the Covid-19 vaccine during the third trimester of pregnancy, which was not associated with adverse maternal outcomes and, moreover, decreased the risk for neonatal adverse outcomes., Tweetable Abstract: Covid-19 vaccine during pregnancy is safe for both mother and fetus., (© 2021 John Wiley & Sons Ltd.)

Key Message: We identified TdPm60 alleles from wild emmer wheat (WEW), an ortholog of Pm60 from T. urartu, which constitutes a strong candidate for PmG16 mildew resistance. Deployment of PmG16 in Israeli modern bread wheat cultivar Ruta improved the resistance to several local Bgt isolates. Wild emmer wheat (WEW), the tetraploid progenitor of durum and bread wheat, is a valuable genetic resource for resistance to powdery mildew fungal disease caused by Blumeria graminis f. sp. tritici (Bgt). PmG16 gene, derived from WEW, confers high resistance to most tested Bgt isolates. We mapped PmG16 to a 1.4-cM interval between the flanking markers uhw386 and uhw390 on Chromosome 7AL. Based on gene annotation of WEW reference genome Zavitan&#95;V1, 34 predicted genes were identified within the ~ 3.48-Mb target region. Six genes were annotated as associated with disease resistance, of which TRIDC7AG077150.1 was found to be highly similar to Pm60, previously cloned from Triticum urartu, and resides in the same syntenic region. The functional molecular marker (FMM) for Pm60 (M-Pm60-S1) co-segregated with PmG16, suggesting the Pm60 ortholog from WEW (designated here as TdPm60) as a strong candidate for PmG16. Sequence alignment identified only eight SNPs that differentiate between TdPm60 and TuPm60. Furthermore, TdPm60 was found to be present also in the WEW donor lines of the powdery mildew resistance genes MlIW172 and MlIW72, mapped to the same region of Chromosome 7AL as PmG16, suggesting that TdPm60 constitutes a candidate also for these genes. Furthermore, screening of additional 230 WEW accessions with Pm60 specific markers revealed 58 resistant accessions from the Southern Levant that harbored TdPm60, while none of the susceptible accessions showed the presence of this gene. Deployment of PmG16 in Israeli modern bread wheat cultivar Ruta conferred resistance against several local Bgt isolates., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The bird cherry-oat aphid ( Rhopalosiphum padi ) is one of the most destructive insect pests in wheat production. To reduce aphid damage, wheat plants have evolved various chemical and physical defense mechanisms. Although these mechanisms have been frequently reported, much less is known about their effectiveness. The tetraploid wild emmer wheat (WEW; Triticum turgidum ssp. dicoccoides ), one of the progenitors of domesticated wheat, possesses untapped resources from its numerous desirable traits, including insect resistance. The goal of this research was to determine the effectiveness of trichomes (physical defense) and benzoxazinoids (BXDs; chemical defense) in aphid resistance by exploiting the natural diversity of WEW. We integrated a large dataset composed of trichome density and BXD abundance across wheat genotypes, different leaf positions, conditions (constitutive and aphid-induced), and tissues (whole leaf and phloem sap). First, we evaluated aphid reproduction on 203 wheat accessions and found large variation in this trait. Then, we chose eight WEW genotypes and one domesticated durum wheat cultivar for detailed quantification of the defense mechanisms across three leaves. We discovered that these defense mechanisms are influenced by both leaf position and genotype, where aphid reproduction was the highest on leaf-1 (the oldest), and trichome density was the lowest. We compared the changes in trichome density and BXD levels upon aphid infestation and found only minor changes relative to untreated plants. This suggests that the defense mechanisms in the whole leaf are primarily anticipatory and unlikely to contribute to aphid-induced defense. Next, we quantified BXD levels in the phloem sap and detected a significant induction of two compounds upon aphid infestation. Moreover, evaluating aphid feeding patterns showed that aphids prefer to feed on the oldest leaf. These findings revealed the dynamic response at the whole leaf and phloem levels that altered aphid feeding and reproduction. Overall, they suggested that trichomes and the BXD 2,4-dihydroxy-7- methoxy-1,4-benzoxazin-3-one (DIMBOA) levels are the main factors determining aphid resistance, while trichomes are more effective than BXDs. Accessions from the WEW germplasm, rich with trichomes and BXDs, can be used as new genetic sources to improve the resistance of elite wheat cultivars., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Singh, Dilkes, Sela and Tzin.)

Stripe rust is a foliar disease in wheat caused by Puccinia striiformis f. tritici . The best way to protect wheat from this disease is by growing resistant cultivars. Tetraploid wheat can serve as a good source of valuable genetic diversity for various traits. Here, we report the mapping of nine stripe rust resistance quantitative trait loci (QTL) effective against P. striiformis f. tritici in China and Israel. We used recombinant inbred lines (RILs) developed from a cross between the durum wheat cultivar Svevo and Triticum dicoccoides accession Zavitan. By genotyping the RIL population of 137 lines using the wheat 90K single-nucleotide polymorphism array, we mapped an adult-plant resistance locus QYrsv.swust-1BL.1 , the most effective QTL, within a 0.75-centimorgan region in T. turgidum subsp. durum 'Svevo' on chromosome arm 1BL, corresponding to the region of 670.7 to 671.5 Mb on the Chinese Spring chromosome arm 1BL. Of the other eight minor-effect stripe rust QTL, seven were from Svevo and mapped on chromosomes 1A, 1B, 2B, 3A, 4A, and 5A, and one was from Zavitan and mapped on chromosome 2A. Several QTL with epistatic effects were identified as well. The markers linked to the resistance QTL can be useful in marker-assisted selection for incorporation of these resistance QTL into both durum and common wheat cultivars.

Background: For over a century, genetic diversity of wheat worldwide was eroded by continual selection for high yields and industrial demands. Wheat landraces cultivated in Israel and Palestine demonstrate high genetic diversity and a potentially wide repertoire of adaptive alleles. While most Israeli-Palestinian wheat landraces were lost in the transition to 'Green Revolution' semi-dwarf varieties, some germplasm collections made at the beginning of the 20th century survived in gene banks and private collections worldwide. However, fragmentation and poor conservation place this unique genetic resource at a high risk of genetic erosion. Herein, we describe a long-term initiative to restore, conserve, and characterize a collection of Israeli and Palestinian wheat landraces (IPLR)., Results: We report on (i) the IPLR construction (n = 932), (ii) the historical and agronomic context to this collection, (iii) the characterization and assessment of the IPLR's genetic diversity, and (iv) a data comparison from two distinct subcollections within IPLR: a collection made by N. Vavilov in 1926 (IPLR-VIR) and a later one (1979-1981) made by Y. Mattatia (IPLR-M). Though conducted in the same eco-geographic space, these two collections were subjected to considerably different conservation pathways. IPLR-M, which underwent only one propagation cycle, demonstrated marked genetic and phenotypic variability (within and between accessions) in comparison with IPLR-VIR, which had been regularly regenerated over ∼90 years., Conclusion: We postulate that long-term ex situ conservation involving human and genotype × environment selection may significantly reduce accession heterogeneity and allelic diversity. Results are further discussed in a broader context of pre-breeding and conservation. © 2019 Society of Chemical Industry., (© 2019 Society of Chemical Industry.)

Background: Leaf and stripe rusts are two major wheat diseases, causing significant yield losses. The preferred way for protecting wheat from rust pathogens is by introgression of rust resistance traits from wheat-related wild species. To avoid genetic drag due to replacement of large wheat chromosomal segments by the alien chromatin, it is necessary to shorten the alien chromosome segment in primary recombinants., Results: Here we report on shortening of an alien chromosome segment in wheat that carries leaf and stripe rust resistance from Sharon goatgrass (Aegilops sharonensis). Rust resistant wheat introgression lines were selected and the alien region was mapped using genotyping by sequencing. Single polymorphic nucleotides (SNP) were identified and used to generate diagnostic PCR markers. Shortening of the alien fragment was achieved by induced homoeologous pairing and lines with shortened alien chromosome were identified using the PCR markers. Further reduction of the segment was achieved in tertiary recombinants without losing the rust resistance., Conclusions: Alien chromatin in wheat with novel rust resistance genes was characterized by SNP markers and shortened by homoeologous recombination to avoid deleterious traits. The resulting wheat lines are resistant to highly virulent races of leaf and stripe rust pathogens and can be used as both resistant wheat in the field and source for gene transfer to other wheat lines/species.

Net blotch (NB) is a major disease of barley caused by the fungus Pyrenophora teres f. teres ( Ptt ), and P. teres f. maculata ( Ptm ). Ptt and Ptm infect the cultivated crop ( Hordeum vulgare ) and its wild relatives ( H. vulgare ssp. spontaneum and H. murinum ssp. glaucum ). The main goal of this research was to study the NB-causing pathogen in the crop center of origin. To address this, we have constructed a Ptt (n = 15) and Ptm (n = 12) collection isolated from three barley species across Israel. Isolates were characterized genetically and phenotypically. Aggressiveness of the isolates was determined based on necrotrophic growth rate on detached leaves of barley. In addition, isolates were genetically characterized by the mating type, followed by phylogenetic analysis, clustering them into seven groups. The analysis showed no significant differentiation of isolates based on either geographic origin, host of origin or form ( Ptt vs. Ptm ). Nevertheless, there was a significant difference in aggressiveness among the isolates regardless of host species, geographic location or sampling site. Moreover, it was apparent that the isolates derived from wild hosts were more variable in their necrotrophic growth rate, compared to isolates sampled from cultivated hosts, thereby suggesting that NB plays a major role in epidemiology at the center of barley origin where most of the diversity lies. Ptm has significantly higher necrotrophic and saprotrophic growth rates than Ptt , and for both a significant negative correlation was found between light intensity exposure and growth rates.

Wheat domestication was a milestone in the rise of agrarian societies in the Fertile Crescent. As opposed to the freely dispersing seeds of its tetraploid progenitor wild emmer, the hallmark trait of domesticated wheat is intact, harvestable spikes. During domestication, wheat acquired recessive loss-of-function mutations in the Brittle Rachis 1 genes, both in the A genome (BTR1-A) and B genome (BTR1-B). In this study, we probe the geographical provenances of these mutations via haplotype analyses of a collection of wild and domesticated accessions. Our results show that the precursor of the domesticated haplotype of BTR1-A was detected in 32% of the wild accessions gathered throughout the Levant, from central Israel to central Turkey. In contrast, the precursor of the domesticated haplotype of BTR1-B, which carries a distinct 11 bp deletion in the promoter region, was found in only 10% of the tested wild accessions, all from the Southern Levant. Moreover, we identified of a single wild emmer accession in Southern Levant that carries the progenitor haplotypes for both BTR1-A and BTR1-B genes. These observations suggest that at least part of the emmer domestication process occurred in Southern Levant, contrary to the widely held view that the northern part of the Fertile Crescent was the center of wheat domestication., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background: Administration of packed red blood cells (PRBC) and fresh frozen plasma (FFP) to women with postpartum hemorrhage (PPH) before and after introduction of a massive transfusion protocol., Methods: The retrospective PPH study cohort of two tertiary centers was identified using blood bank records, verified by patient electronic medical records. We identified women transfused with ≥3 units PRBC in a short time period within 24 hours of delivery. Since 2010, both centers have used a protocol using 1:1 FFP:PRBC ratios. Demographic, obstetric, and blood management data were retrieved from medical records. Outcome measures included estimated blood loss, blood product administration, and hematologic variables., Results: 273 women were included, 112 (41.0%) prior to introduction of the protocol (2004-2009) and 161 (59.0%) afterwards (2010-2014). The frequency of women managed with 1:1 FFP:PRBC ratios was similar before 55/112 (49.1%) and after 83/161 (51.6%) introduction of the protocol (P=0.69). There was strong correlation between PRBC units transfused and the FFP:PRBC transfusion ratio (R-square 0.866, P <0.0001), demonstrating that as the number of transfused PRBC units increased, FFP:PRBC ratios became closer to 1:1. There were no outcome differences between women managed before and after introduction of the protocol., Conclusions: Among women with PPH receiving ≥3 PRBC units within a short period of time, it appears that factors other than the existence of our massive transfusion protocol influence the number and ratio of PRBC and FFP units transfused. Blood products were not transfused according to exact ratios, even when guided by a protocol., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Yellow rust, caused by Puccinia striiformis f. sp. tritici (Pst), is a devastating fungal disease threatening much of global wheat production. Race-specific resistance (R)-genes are used to control rust diseases, but the rapid emergence of virulent Pst races has prompted the search for a more durable resistance. Here, we report the cloning of Yr15, a broad-spectrum R-gene derived from wild emmer wheat, which encodes a putative kinase-pseudokinase protein, designated as wheat tandem kinase 1, comprising a unique R-gene structure in wheat. The existence of a similar gene architecture in 92 putative proteins across the plant kingdom, including the barley RPG1 and a candidate for Ug8, suggests that they are members of a distinct family of plant proteins, termed here tandem kinase-pseudokinases (TKPs). The presence of kinase-pseudokinase structure in both plant TKPs and the animal Janus kinases sheds light on the molecular evolution of immune responses across these two kingdoms.

Following publication of the original article [1], the authors reported the need for a more detailed acknowledgement of the source of the samples that were analyzed and their coordinates, which are discussed in the 'Methods' section of the article. This Correction provides an addition to the 'Methods' section, and a subsequently revised 'Acknowledgements' and 'Availability of data and materials' section.

Key Message: NGS-assisted super pooling emerging as powerful tool to accelerate gene mapping and haplotype association analysis within target region uncovering specific linkage SNPs or alleles for marker-assisted gene pyramiding. Conventional gene mapping methods to identify genes associated with important agronomic traits require significant amounts of financial support and time. Here, a single nucleotide polymorphism (SNP)-based mapping approach, RNA-Seq and SNP array assisted super pooling analysis, was used for rapid mining of a candidate genomic region for stripe rust resistance gene Yr26 that has been widely used in wheat breeding programs in China. Large DNA and RNA super-pools were genotyped by Wheat SNP Array and sequenced by Illumina HiSeq, respectively. Hundreds of thousands of SNPs were identified and then filtered by multiple filtering criteria. Among selected SNPs, over 900 were found within an overlapping interval of less than 30 Mb as the Yr26 candidate genomic region in the centromeric region of chromosome arm 1BL. The 235 chromosome-specific SNPs were converted into KASP assays to validate the Yr26 interval in different genetic populations. Using a high-resolution mapping population (> 30,000 gametes), we confined Yr26 to a 0.003-cM interval. The Yr26 target region was anchored to the common wheat IWGSC RefSeq v1.0 and wild emmer WEWSeq v.1.0 sequences, from which 488 and 454 kb fragments were obtained. Several candidate genes were identified in the target genomic region, but there was no typical resistance gene in either genome region. Haplotype analysis identified specific SNPs linked to Yr26 and developed robust and breeder-friendly KASP markers. This integration strategy can be applied to accelerate generating many markers closely linked to target genes/QTL for a trait of interest in wheat and other polyploid species.

Stem rust (caused by Puccinia graminis f. sp. tritici), leaf rust (P. triticina), and stripe rust (P. striiformis f. sp. tritici) rank among the most important diseases of wheat worldwide. The development of resistant cultivars is the preferred method of controlling rust diseases because it is environmentally benign and also cost effective. However, new virulence types often arise in pathogen populations, rendering such cultivars vulnerable to losses. The identification of new sources of resistance is key to providing long-lasting disease control against the rapidly evolving rust pathogens. Thus, the objective of this research was to evaluate the wild wheat relative Aegilops longissima for resistance to stem rust, leaf rust, and stripe rust at the seedling stage in the greenhouse. A diverse collection of 394 accessions of the species, mostly from Israel, was assembled for the study, but the total number included in any one rust evaluation ranged from 308 to 379. With respect to stem rust resistance, 18.2 and 80.8% of accessions were resistant to the widely virulent U.S. and Kenyan P. graminis f. sp. tritici races of TTTTF and TTKSK, respectively. The percentage of accessions exhibiting resistance to the U.S. P. triticina races of THBJ and BBBD was 65.9 and 52.2%, respectively. Over half (50.1%) of the Ae. longissima accessions were resistant to the U.S. P. striiformis f. sp. tritici race PSTv-37. Ten accessions (AEG-683-23, AEG-725-15, AEG-803-49, AEG-1274-20, AEG-1276-22, AEG-1471-15, AEG-1475-19, AEG-2974-0, AEG-4005-20, and AEG-8705-10) were resistant to all races of the three rust pathogens used in this study. Distinct differences in the geographic distribution of resistance and susceptibility were found in Ae. longissima accessions from Israel in response to some rust races. To P. graminis f. sp. tritici race TTKSK, populations with a very high frequency of resistance were concentrated in the central and northern part of Israel, whereas populations with a comparatively higher frequency of susceptibility were concentrated in the southern part of the country. The reverse trend was observed with respect to P. striiformis f. sp. tritici race PSTv-37. The results from this study demonstrate that Ae. longissima is a rich source of rust resistance genes for wheat improvement.

Background: Snake melon (Cucumis melo var. flexuosus, "Faqqous") is a traditional and ancient vegetable in the Mediterranean area. A collection of landraces from 42 grower fields in Israel and Palestinian territories was grown and characterized in a "Common Garden" rain-fed experiment, at the morphological-horticultural and molecular level using seq-DArT markers., Results: The different landraces ("populations") showed extensive variation in morphology and quantitative traits such as yield and femaleness, and clustered into four horticultural varieties. Yield was assessed by five harvests along the season, with middle harvests producing the highest yields. Yield correlated with early vigor, and with femaleness, but not with late vigor. At the molecular level, 2784 SNP were produced and > 90% were mapped to the melon genome. Populations were very polymorphic (46-72% of the markers biallelic in a 4 individuals sample), and observed heterozygosity was higher than the expected, suggesting gene flow among populations and extensive cross pollination among individuals in the field. Genetic distances between landraces were significantly correlated with the geographical distance between collecting sites, and with long term March precipitation average; variation in yield correlated with April temperature maxima., Conclusions: The extensive variation suggests that selection of local snake melon could result in yield improvement. Correlations between traits and climatic variables could suggest local adaptation of landraces to the diverse environment in which they evolved. This study stresses the importance of preserving this germplasm, and its potential for breeding better snake melons as an heirloom crop in our region.

Wheat stem rust, a devastating disease of wheat and barley caused by the fungal pathogen Puccinia graminis f. sp. tritici , was largely eradicated in Western Europe during the mid-to-late twentieth century. However, isolated outbreaks have occurred in recent years. Here we investigate whether a lack of resistance in modern European varieties, increased presence of its alternate host barberry and changes in climatic conditions could be facilitating its resurgence. We report the first wheat stem rust occurrence in the United Kingdom in nearly 60 years, with only 20% of UK wheat varieties resistant to this strain. Climate changes over the past 25 years also suggest increasingly conducive conditions for infection. Furthermore, we document the first occurrence in decades of P. graminis on barberry in the UK . Our data illustrate that wheat stem rust does occur in the UK and, when climatic conditions are conducive, could severely harm wheat and barley production., Competing Interests: The authors declare no competing financial interests.

Many accessions of the wheat wild relative Sharon goatgrass ( Eig., ) are resistant to African races of the stem rust pathogen (i.e., Ug99 group races), which currently threaten wheat production worldwide. A procedure was designed to introgress the respective resistances to specific bread wheat genomes by producing plants homozygous for the A and B genomes and hemizygous for the D and S genomes or homozygous for the A and D genomes and hemizygous for the B and S genomes. In these genotypes, which lack the allele, homeologous pairing was expected mainly between chromosomes of the D and S genomes or B and S genomes, respectively. An antigametocidal (AG) wheat mutant () was used to overcome gametocidal effects. Wheat lines initially found resistant at the seedling stage were also highly resistant at the adult plant stage in rust nurseries established in the field. DNA of 41 selected homozygous resistant lines, analyzed by the Axiom wheat 820K SNP array, showed alien chromatin mainly in wheat chromosomes 1B, 1D, and 5B. This work suggests that, in most cases, it is possible to target introgressions into the homeologous chromosome of a selected genome of bread wheat., (Copyright © 2017 Crop Science Society of America.)

Background: Biliary atresia is a progressive disease presenting with jaundice, and is the most common indication for liver transplantation in the pediatric population. Prenatal series have yielded conflicting results concerning a possible association between BA and prenatal nonvisualization of the gallbladder., Aims: This retrospective case series was performed to assess the association between biliary atresia, prenatal nonvisualization of the gallbladder and other sonographic signs., Study Design/subjects: We identified biliary atresia patients who underwent a Kasai procedure by a single pediatric surgeon and/or follow up by a single pediatric gastroenterologist. Axial plane images and/or video recordings were scrutinized for sonographic signs of biliary atresia on the second trimester anomaly scan., Outcome Measures: Proportion of biliary atresia cases with prenatal sonographic signs., Results: Twenty five charts of children with biliary and high quality prenatal images were retrieved. 6/25 (24%) of cases analyzed had prenatal nonvisualization of the gallbladder or a small gallbladder on the prenatal scan. Two cases had biliary atresia splenic malformation syndrome. None of the cases had additional sonographic markers of biliary atresia., Conclusions: Our study suggests that in addition to the well-established embryonic and cystic forms, an additional type can be suspected prenatally, which is characterized by prenatal nonvisualization of the gallbladder in the second trimester. This provides additional evidence that some cases of BA are of fetal rather than perinatal onset and may have important implications for prenatal diagnosis, for counseling and for research of the disease's etiology and pathophysiology., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Wheat ( Triticum spp.) is one of the founder crops that likely drove the Neolithic transition to sedentary agrarian societies in the Fertile Crescent more than 10,000 years ago. Identifying genetic modifications underlying wheat's domestication requires knowledge about the genome of its allo-tetraploid progenitor, wild emmer ( T. turgidum ssp. dicoccoides ). We report a 10.1-gigabase assembly of the 14 chromosomes of wild tetraploid wheat, as well as analyses of gene content, genome architecture, and genetic diversity. With this fully assembled polyploid wheat genome, we identified the causal mutations in Brittle Rachis 1 ( TtBtr1 ) genes controlling shattering, a key domestication trait. A study of genomic diversity among wild and domesticated accessions revealed genomic regions bearing the signature of selection under domestication. This reference assembly will serve as a resource for accelerating the genome-assisted improvement of modern wheat varieties., (Copyright © 2017, American Association for the Advancement of Science.)

Key Message: We identified two novel wheat stem rust resistance genes, Sr-1644-1Sh and Sr-1644-5Sh in Aegilops sharonensis that are effective against widely virulent African races of the wheat stem rust pathogen. Stem rust is one of the most important diseases of wheat in the world. When single stem rust resistance (Sr) genes are deployed in wheat, they are often rapidly overcome by the pathogen. To this end, we initiated a search for novel sources of resistance in diverse wheat relatives and identified the wild goatgrass species Aegilops sharonesis (Sharon goatgrass) as a rich reservoir of resistance to wheat stem rust. The objectives of this study were to discover and map novel Sr genes in Ae. sharonensis and to explore the possibility of identifying new Sr genes by genome-wide association study (GWAS). We developed two biparental populations between resistant and susceptible accessions of Ae. sharonensis and performed QTL and linkage analysis. In an F 6 recombinant inbred line and an F 2 population, two genes were identified that mapped to the short arm of chromosome 1S sh , designated as Sr-1644-1Sh, and the long arm of chromosome 5S sh , designated as Sr-1644-5Sh. The gene Sr-1644-1Sh confers a high level of resistance to race TTKSK (a member of the Ug99 race group), while the gene Sr-1644-5Sh conditions strong resistance to TRTTF, another widely virulent race found in Yemen. Additionally, GWAS was conducted on 125 diverse Ae. sharonensis accessions for stem rust resistance. The gene Sr-1644-1Sh was detected by GWAS, while Sr-1644-5Sh was not detected, indicating that the effectiveness of GWAS might be affected by marker density, population structure, low allele frequency and other factors.

Correction for 'Distinctive hippocampal zinc distribution patterns following stress exposure in an animal model of PTSD' by Hagit Sela et al., Metallomics, 2017, 9, 323-333.

Emerging evidence suggests that zinc (Zn) deficiency is associated with depression and anxiety in both human and animal studies. The present study sought to assess whether there is an association between the magnitude of behavioral responses to stress and patterns of Zn distribution. The work has focused on one case study, the association between an animal model of posttraumatic stress disorder (PTSD) and the Zn distribution in the rat hippocampus. Behaviors were assessed with the elevated plus-maze and acoustic startle response tests 7 days later. Preset cut-off criteria classified exposed animals according to their individual behavioral responses. To further characterize the distribution of Zn that occurs in the hippocampus 8 days after the exposure, laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) imaging was used. It has been found that Zn distribution in the dentate gyrus (DG) sub-region in the hippocampus is clearly more widely spread for rats that belong to the extreme behavioral response (EBR) group as compared to the control group. Comparison of the Zn concentration changes in the cornu ammonis 1 (CA1) and the DG sub-regions of the hippocampus shows that the concentration changes are statistically significantly higher in the EBR rats compared to the rats in the control and minimal behavioral response (MBR) groups. In order to understand the mechanism of stress-induced hippocampal Zn dyshomeostasis, relative quantitative analyses of metallothionein (MT), B-cell lymphoma 2 (Bcl-2) and caspase 3 immunoreactivity were performed. Significant differences in the number of caspase-ir and Bcl-2 cells were found in the hippocampal DG sub-region between the EBR group and the control and MBR groups. The results of this study demonstrate a statistically significant association between the degree of behavioral disruption resulting from stress exposure and the patterns of Zn distribution and concentration changes in the various hippocampal regions. Taken together, these findings indicate that Zn distribution patterns play an active role in the neurobiological response to predator scent stress.

We hypothesized that postnatal absolute nucleated red blood cell (aNRBC) counts would be elevated in premature infants with hemodynamically significant patent ductus arteriosus (PDA), reflecting intrauterine hypoxia. PDA severity was assessed and categorized echocardiographically. aNRBC counts were significantly correlated with ductal severity (Pearson correlation: P = .007). At the extremes, aNRBC levels were 3770 (728, 6015) hemodynamically significant PDA vs 865 (483, 2528) closed ductus., (Copyright © 2016 Elsevier Inc. All rights reserved.)

The genetic bottlenecks associated with plant domestication and subsequent selection in man-made agroecosystems have limited the genetic diversity of modern crops and increased their vulnerability to environmental stresses. Wild emmer wheat, the tetraploid progenitor of domesticated wheat, distributed along a wide range of ecogeographical conditions in the Fertile Crescent, has valuable "left behind" adaptive diversity to multiple diseases and environmental stresses. The biotic and abiotic stress responses are conferred by series of genes and quantitative trait loci (QTLs) that control complex resistance pathways. The study of genetic diversity, genomic organization, expression profiles, protein structure and function of biotic and abiotic stress-resistance genes, and QTLs could shed light on the evolutionary history and adaptation mechanisms of wild emmer populations for their natural habitats. The continuous evolution and adaptation of wild emmer to the changing environment provide novel solutions that can contribute to safeguarding food for the rapidly growing human population.

Key Message: The wheat stripe rust resistance gene Yr36 ( WKS1 ) with a unique kinase-START domain architecture is highly conserved in wild emmer wheat natural populations. Wild emmer wheat (Triticum dicoccoides) populations have developed various resistance strategies against the stripe rust pathogen Puccinia striiformis f. sp. tritici (Pst). The wild emmer gene, Yr36 (WKS1), which confers partial resistance to a broad spectrum of Pst races, is composed of a kinase and a START lipid-binding domain, a unique gene architecture found only in the Triticeae tribe. The analysis of 435 wild emmer accessions from a broad range of natural habitats revealed that WKS1 and its paralogue WKS2 are present only in the southern distribution range of wild emmer in the Fertile Crescent, supporting the idea that wheat domestication occurred in the northern populations. An analysis of full-length WKS1 sequence from 54 accessions identified 15 different haplotypes and very low-nucleotide diversity (π = 0.00019). The high level of WKS1 sequence conservation among wild emmer populations is in contrast to the high level of diversity previously observed in NB-LRR genes (e.g., Lr10 and Pm3). This phenomenon may reflect the different resistance mechanisms and different evolutionary pathways that shaped these genes, and may shed light on the evolution of genes that confer partial resistance to stripe rust. Only five WKS1 coding sequence haplotypes were revealed among all tested accessions, encoding four different putative WKS1 proteins (designated P0, P1, P2, and P3). Infection tests showed that P0, P1, and P3 haplotypes display a resistance response, while P2 displayed a susceptible response. These results show that the WKS1 proteins (P0, P1, and P3) can be useful to improve wheat resistance to stripe rust.

Background: The blood brain barrier (BBB) controls the brain microenvironment and limits penetration of the central nervous system (CNS) by chemicals, thus creating an obstacle to many medical imaging and treatment procedures. Research efforts to identify viable routes of BBB penetration have focused on structures such as micelles, polymeric nanoparticles and liposomes as drug carriers, however, many of them failed to provide unequivocal proof of BBB penetration. Here we proved that gold nanoparticles (AuNPs) penetrate the BBB in rats to reach brain regions., Results: Injection of AuNPs to the abdominal cavity of rats resulted in levels of gold found in blood, urine, brain regions and body organs. After perfusion the concentration of gold in brain regions diminished dramatically indicating that most of the gold was in venous blood and not in the brain tissues. Injection of Na, K or Ca ion channel blockers reduced BBB penetration by half. A biological half-life of 12.9 ± 4.9 h was found for the gold nanoparticles. Possible mechanisms for the transport of AuNPs through the BBB are discussed., Conclusions: BBB penetration by AuNPs is spontaneous without the application of an external field. A major amount of gold resides in blood vessels therefore perfusion required. Ion channel blockers can be used to control the transport of AuNPs.

A flow injection manifold incorporating a solid phase chelating resin (Toyopearl AF-Chelate-650) is reported for the preconcentration of dissolved metals from seawater, with a focus on investigating the effect of the loading pH, wash solution composition and wash time. Cobalt, iron, lead and vanadium have been used as target analytes with contrasting oceanographic behaviour. Quadrupole ICP-MS has been used for detection to make the approach accessible to most laboratories and a collision/reaction cell has been incorporated to minimise polyatomic interferences. Results for the seawater CRM NASS-6 and two GEOTRACES reference materials were in good agreement with the certified/consensus values, demonstrating the suitability of the approach for the determination of trace metals in seawater. The experimental design used allowed a thorough investigation of the uncertainty contribution from each method parameter to the overall expanded uncertainty of the measurement. The results showed that the parameters making the largest contributions were the precision of the peak area measurement and the uncertainty associated with the slope of the calibration curve. Therefore, these are the critical parameters that should be targeted in order to reduce the overall measurement uncertainty. For iron, the wash blank also gave a measureable contribution., (Copyright © 2014 Elsevier B.V. All rights reserved.)