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Globally, soil salinization is becoming increasingly prevalent, due to local hydrogeologic phenomena, climate change and anthropogenic activities. This has significantly curtailed current world food production and limits future production potential. In the prairie region of North America, sulfate salts, rather than sodium chloride, are often the predominant cause of soil degradation. In order to amend soil quality, revegetate salt-affected sites and recover economic loss associated with soil salinization, the establishment of short-rotation coppice plantations with willows (Salix spp.) has been suggested as a possible solution. To screen for the best candidates for such an application, 20 hybrid and 16 native willow genotypes were treated with three different salt conditions for 3 months. The treatments were designed to reflect the salt composition and concentrations on North American prairies. Under moderate salinity treatment (7 dS m−1), hybrid willows had better growth, as they established quickly while managing salt transport and mineral nutrition balance. However, native willows showed higher potential for long-term survival under severe salinity treatment (14 dS m−1), showing a lower sodium:potassium ratio in roots and better photosynthetic performance. Two native willow genotypes with high osmotic and salinity tolerance indices, specifically LAR-10 and MJW-9, are expected to show superior potential for remediating salt-affected sites. In addition, we observed significantly higher sulfate/sulfur concentrations in both leaf and root tissues in response to the severe salinity treatment, shedding light on the effect of sulfate salinity on sulfate uptake, and potentially sulfur metabolism in plants.

Genome-wide gene expression studies have become a routine approach due to the advances in sequencing technologies, their ease of use, and increasing affordability. Simultaneous investigation of small RNA expression adds further valuable information but is not adopted as widely yet. Both RNA-seq and small RNA-seq benefit from the use of specific cell types. Here, we describe a protocol for the isolation of male meiotic cells from maize or wheat plants, along with the application of downstream RNA sequencing, extendable to other -omics approaches., Series: Methods in Molecular Biology

Background Molecular analysis of meiosis has been hindered by difficulties in isolating high purity subpopulations of sporogenous cells representing the succeeding stages of meiosis. Isolation of purified male meiocytes from defined meiotic stages is crucial in discovering meiosis specific genes and associated regulatory networks. Results We describe an optimized method termed MeioCapture for simultaneous isolation of uncontaminated male meiocytes from wheat (Triticum spp.), specifically from the pre-meiotic G2 and the five sub-stages of meiotic prophase I. The MeioCapture protocol builds on the traditional anther squash technique and the capillary collection method, and involves extrusion of intact sporogenous archesporial columns (SACs) containing meiocytes. This improved method exploits the natural meiotic synchrony between anthers of the same floret, the correlation between the length of anthers and meiotic stage, and the occurrence of meiocytes in intact SACs largely free of somatic cells. The main advantage of MeioCapture, compared to previous methods, is that it allows simultaneous collection of meiocytes from different sub-stages of prophase I at a very high level of purity, through correlation of stages with anther sizes. A detailed description is provided for all steps, including the collection of tissue, isolation and size sorting of anthers, extrusion of intact SACs, and staging of meiocytes. Precautions for individual steps throughout the procedure are also provided to facilitate efficient isolation of pure meiocytes. The proof-of-concept was successfully established in wheat, and a light microscopic atlas of meiosis, encompassing all stages from pre-meiosis to telophase II, was developed. Conclusion The MeioCapture method provides an essential technique to study the molecular basis of chromosome pairing and exchange of genetic information in wheat, leading to strategies for manipulating meiotic recombination frequencies. The method also provides a foundation for similar studies in other crop species. Electronic supplementary material The online version of this article (10.1186/s12870-018-1514-z) contains supplementary material, which is available to authorized users.

Background: Molecular analysis of meiosis has been hindered by difficulties in isolating high purity subpopulations of sporogenous cells representing the succeeding stages of meiosis. Isolation of purified male meiocytes from defined meiotic stages is crucial in discovering meiosis specific genes and associated regulatory networks. Results: We describe an optimized method termed MeioCapture for simultaneous isolation of uncontaminated male meiocytes from wheat (Triticum spp.), specifically from the pre-meiotic G2 and the five sub-stages of meiotic prophase I. The MeioCapture protocol builds on the traditional anther squash technique and the capillary collection method, and involves extrusion of intact sporogenous archesporial columns (SACs) containing meiocytes. This improved method exploits the natural meiotic synchrony between anthers of the same floret, the correlation between the length of anthers and meiotic stage, and the occurrence of meiocytes in intact SACs largely free of somatic cells. The main advantage of MeioCapture, compared to previous methods, is that it allows simultaneous collection of meiocytes from different sub-stages of prophase I at a very high level of purity, through correlation of stages with anther sizes. A detailed description is provided for all steps, including the collection of tissue, isolation and size sorting of anthers, extrusion of intact SACs, and staging of meiocytes. Precautions for individual steps throughout the procedure are also provided to facilitate efficient isolation of pure meiocytes. The proof-of-concept was successfully established in wheat, and a light microscopic atlas of meiosis, encompassing all stages from pre-meiosis to telophase II, was developed. Conclusion: The MeioCapture method provides an essential technique to study the molecular basis of chromosome pairing and exchange of genetic information in wheat, leading to strategies for manipulating meiotic recombination frequencies. The method also provides a foundation for similar studies in other crop species., Erratum published in volume 19, article 178, May 2, 2019. DOI: 10.1186/s12870-019-1780-4

Phytate, the storage form of P in seeds, is not well digested by monogastrics, thereby contributing to micronutrient deficiency, decreased feed efficiency, and environmental pollution. This research was aimed at developing a single nucleotide polymorphism (SNP) based genetic linkage map and mapping genomic regions associated with phytic acid-phosphorus (PAP) concentration using a recombinant inbred line (RIL) population (PR -15) derived from a cross between a low phytate (low phytic acid [lpa]) mutant pea (Pisum sativum L.) genotype, 1-2347-144, and a normal phytate cultivar CDC Meadow. A total of 163 RILs were genotyped using a 1536-SNP Illumina GoldenGate array. Three hundred and sixty-seven polymorphic SNP markers ordered into seven linkage groups (LGs) were used to generate a linkage map with a total length of 437.2 cM. PR -15 lines were grown in replicated field trails in Saskatoon and Rosthern, SK, in 2012 and 2013. Chi-square statistics confirmed the single gene inheritance of PA-P concentration in these RILs. Phytic acidphosphorus (PA-P) phenotype was mapped to LG5. Iron bioavailability (FEBIO) of PR -15 lines estimated using the Caco-2 cell culture bioassay was negatively correlated with PA-P concentration. A quantitative trait locus (QTL) for FEBIO was mapped on to the same location on LG5 as phytic acid concentration. The QTL with a maximum LOD score of 15.1 explained 60.5% of the phenotypic variation in FEBIO. The markers flanking this QTL region can be employed in marker-assisted selection to select pea lines with low phytate and greater Fe bioavailability.

Development of pea cultivars with improved resistance to ascochyta blight disease has been hindered due to lack of strong resistance. The objective of this study was to identify single nucleotide polymorphisms (SNPs) within the candidate genes associated with ascochyta blight resistance that can be used to aid selection. A total of 54 diverse Pisum sativum accessions from eastern Europe, western Europe, Australia, and Canada were genotyped and phenotyped for disease reaction. Fifteen SNPs were detected within candidate genes associated with reaction to ascochyta blight, of which SNP loci PsDof1p308 and RGA-G3Ap103 had significant associations with ascochyta blight scores. Further, PsDof1p308 showed significant association with disease score when tested on a recombinant inbred line population (PR-15) developed from a cross between ‘CDC 1-2347-144’ and ‘CDC Meadow’. SNPs identified in this study have the potential to aid selection of pea cultivars with improved disease resistance.

Intraspecific variations in seasonal phenology and growth physiology reflect adaptation to local climate. To explore the patterns of local adaptation along latitudinal and longitudinal clines, we used thirty-four populations ofSalix eriocephalasourced from its natural ranges across Canada. The genotypes were examined for 6 phenology and 19 ecophysiology traits over two growing seasons under common garden condition. Photosynthetic assimilation rate (A) increased with increasein latitude when measured during free growth. In spite, the negative correlation between stomatal density and stomatal conductance (gs), higherAis facilitatedvialarger pore length among genotypes from short growing seasons. In addition, higherA, was positively associated with total leafnitrogen and leaf mass per unit area. No population level differences wereobserved for water use-efficiency (Δ13C), however nitrogen isotope discrimination (δ15N) displayed latitudinalclines. Growing season phenological traits considered in this study accounted highheritability (H2= 0.65-0.94).Melampsorarust infestation also displayed a strong latitudinal cline with high-latitude genotypes being more susceptible. Overall, the results support the hypothesis that functional trait variations are largely explained by climate of origin and facilitate selection of parents with superior adaptive traits in the Canadian willow improvement program forbioenergy and environmental applications.

Plant breeders and agricultural scientists of the 21st century are challenged to increase the yield potentials of crops to feed the growing world population. Climate change, the resultant stresses and increasing nutrient deficiencies are factors that are to be considered in designing modern plant breeding pipelines. Underutilized food legumes have the potential to address these issues and ensure food security in developing nations of the world. Food legumes in the past have drawn limited research funding and technological attention when compared to cereal crops. Physiological breeding strategies that were proven to be successful in cereals are to be adapted to legume crop improvement to realize their potential. The gap between breeders and physiologists should be narrowed by collaborative approaches to understand complex traits in legumes. This review discusses the potential of physiology based approaches in food legume breeding and how they impact yield gains and abiotic stress tolerance in these crops. The influence of roots and root system architectures in food legumes’ breeding is also discussed. Molecular breeding to map the relevant physiological traits and the potentials of gene editing those traits are detailed. It is imperative to unlock the potentials of these underutilized crops to attain sustainable environmental and nutritional food security.

Low phytic acid (lpa) crops are low in phytic acid and high in inorganic phosphorus (Pi). In this study, two lpa pea genotypes, 1-150-81, 1-2347-144, and their progenitor CDC Bronco were grown in field trials for two years. The lpa genotypes were lower in IP6 and higher in Pi when compared to CDC Bronco. The total P concentration was similar in lpa genotypes and CDC Bronco throughout the seed development. The action of myo-inositol phosphate synthase (MIPS) (EC 5.5.1.4) is the first and rate-limiting step in the phytic acid biosynthesis pathway. Aiming at understanding the genetic basis of the lpa mutation in the pea, a 1530 bp open reading frame of MIPS was amplified from CDC Bronco and the lpa genotypes. Sequencing results showed no difference in coding sequence in MIPS between CDC Bronco and lpa genotypes. Transcription levels of MIPS were relatively lower at 49 days after flowering (DAF) than at 14 DAF for CDC Bronco and lpa lines. This study elucidated the rate and accumulation of phosphorus compounds in lpa genotypes. The data also demonstrated that mutation in MIPS was not responsible for the lpa trait in these pea lines.

Key message Gene-based SNPs were identified and mapped in pea using five recombinant inbred line populations segregating for traits of agronomic importance. Abstract Pea (Pisum sativum L.) is one of the world’s oldest domesticated crops and has been a model system in plant biology and genetics since the work of Gregor Mendel. Pea is the second most widely grown pulse crop in the world following common bean. The importance of pea as a food crop is growing due to its combination of moderate protein concentration, slowly digestible starch, high dietary fiber concentration, and its richness in micronutrients; however, pea has lagged behind other major crops in harnessing recent advances in molecular biology, genomics and bioinformatics, partly due to its large genome size with a large proportion of repetitive sequence, and to the relatively limited investment in research in this crop globally. The objective of this research was the development of a genome-wide transcriptome-based pea single-nucleotide polymorphism (SNP) marker platform using next-generation sequencing technology. A total of 1,536 polymorphic SNP loci selected from over 20,000 non-redundant SNPs identified using deep transcriptome sequencing of eight diverse Pisum accessions were used for genotyping in five RIL populations using an Illumina GoldenGate assay. The first high-density pea SNP map defining all seven linkage groups was generated by integrating with previously published anchor markers. Syntenic relationships of this map with the model legume Medicago truncatula and lentil (Lens culinaris Medik.) maps were established. The genic SNP map establishes a foundation for future molecular breeding efforts by enabling both the identification and tracking of introgression of genomic regions harbouring QTLs related to agronomic and seed quality traits. Electronic supplementary material The online version of this article (doi:10.1007/s00122-014-2375-y) contains supplementary material, which is available to authorized users.

Conventional breeding of Musa that is based mainly on mass phenotypic recurrent selection is handicapped by a number of factors. The rapid development of molecular biology techniques and their application to plant breeding has resulted in signifi cant genetic gains in agricultural crops. Marker assisted breeding will be very useful for a crop like banana that has a relatively long life cycle. DNA markers are being sought for several characters of importance in Musa including resistance to pests and diseases. Achievements and prospects of molecular breeding for black Sigatoka, Fusarium, Banana bunchy top virus (BBTV), nematodes and Xanthomonas wilt resistance are discussed. In addition gains made in nutritional enhancement of banana are described. The development of modern plant molecular and quantitative genetics in the last two decades has the potential to revolutionize what has mostly been experienced-based empirical plant breeding. This chapter outlines the value of modern molecular tools for molecular breeding of banana.