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Background. Plant chloroplast genome have conservative structure, but its nucleotide sequence is polymorphous due to which cpDNA fragments are often used in taxonomic and phylogenetic studies. Despite the widespread distribution and use of Fabeae species, mainly peas ( Pisum ), data on the intraspecific diversity of cpDNA fragments are almost absent. The aim of the work was to analyze the intraspecific variability of three cpDNA spacers in Pisum. Materials and methods. As a result of the work, intergenic spacers trnY – trnT , trnH – psbA and rpoB – trnC in 38 accessions of the Pisum and related Fabeae species were sequenced. Despite the fact that the selected chloroplast fragments are generally considered to be sufficiently variable in plants and are often used for phylogenetic studies, Pisum accessions have been found to have no intraspecific differences in two of the three spacers sequences analyzed. Results and conclusion. A total 97 SNPs were detected in Pisum accessions, seven of them distinguished P. sativum from P. fulvum . The most variable of the analyzed fragments was the intergenic spacer rpoB–trnC . Based on rpoB–trnC sequence 17 haplotypes in P. sativum and four haplotypes in P. fulvum were revealed. The cpDNA sequencing data were used for a phylogenetic analysis. On the obtained tree Vavilovia formosa accession formed a separate branch from pea accessions. All Pisum accessions fall in one cluster, split into distinct P. sativum and P. fulvum subclusters (BI = 99%).

International audience; Legumes of the Fabeae tribe form nitrogen-fixing root nodules resulting from symbiotic interaction with the soil bacteria Rhizobium leguminosarum symbiovar viciae ( Rlv ). These bacteria are all potential symbionts of the Fabeae hosts but display variable partner choice when co-inoculated in mixture. Because partner choice and symbiotic nitrogen fixation mostly behave as genetically independent traits, the efficiency of symbiosis is often suboptimal when Fabeae legumes are exposed to natural Rlv populations present in soil. A core collection of 32 Rlv bacteria was constituted based on the genomic comparison of a collection of 121 genome sequences, representative of known worldwide diversity of Rlv . A variable part of the nodD gene sequence was used as a DNA barcode to discriminate and quantify each of the 32 bacteria in mixture. This core collection was co-inoculated on a panel of nine genetically diverse Pisum sativum , Vicia faba , and Lens culinaris genotypes. We estimated the relative Early Partner Choice (EPC) of the bacteria with the Fabeae hosts by DNA metabarcoding on the nodulated root systems. Comparative genomic analyses within the bacterial core collection identified molecular markers associated with host-dependent symbiotic partner choice. The results revealed emergent properties of rhizobial populations. They pave the way to identify genes related to important symbiotic traits operating at this level.

The amount of DNA per nucleus, usually expressed in terms of the amount within a haploid chromosome set (C-value), is known to have significant impacts on morphological and physiological features in plants. Among these features, C-value influences replication time and hence duration of the whole cell cycle, as well as sizes of cells. The Fabeae tribe of the family Leguminosae (Fabaceae) is remarkable in having both annual and perennial species and the largest C-values in the family. Polyploidy is rare in this tribe. This work aims to study the correlation between annuality/perenniality, C-value and some morphological characteristics of reproductive organs, such as the number of pollen grains, ovules, flowers per inflorescence as well as pollen and flower size, in annual and perennial species within the tribe Fabeae (Vicieae). The average C-value of perennials is statistically significantly higher than of annuals. Compared with perennials, annuals are mostly characterized by single- or few-flowered inflorescences and fewer ovules per carpel independently of flower size. All floral characteristics exhibit a range of intraspecific variation thus complicating the estimation of precise impact of C-value on phenotype. Features of the reproductive system in the Fabeae are therefore partly correlated with C-value, most probably mediated through the interaction between ecological adaptation of species with their life cycle duration.

Satellite repeats are major sequence constituents of centromeres in many plant and animal species. Within a species, a single family of satellite sequences typically occupies centromeres of all chromosomes and is absent from other parts of the genome. Due to their common origin, sequence similarities exist among the centromere-specific satellites in related species. Here, we report a remarkably different pattern of centromere evolution in the plant tribe Fabeae, which includes genera Pisum, Lathyrus, Vicia, and Lens. By immunoprecipitation of centromeric chromatin with CENH3 antibodies, we identified and characterized a large and diverse set of 64 families of centromeric satellites in 14 species. These families differed in their nucleotide sequence, monomer length (33–2,979 bp), and abundance in individual species. Most families were species-specific, and most species possessed multiple (2–12) satellites in their centromeres. Some of the repeats that were shared by several species exhibited promiscuous patterns of centromere association, being located within CENH3 chromatin in some species, but apart from the centromeres in others. Moreover, FISH experiments revealed that the same family could assume centromeric and noncentromeric positions even within a single species. Taken together, these findings suggest that Fabeae centromeres are not shaped by the coevolution of a single centromeric satellite with its interacting CENH3 proteins, as proposed by the centromere drive model. This conclusion is also supported by the absence of pervasive adaptive evolution of CENH3 sequences retrieved from Fabeae species.

In the 1960s–1980s, the Vavilov Institute of Plant Industry, known worldwide as VIR, organized a substantial series of studies dedicated to a Caucasian endemic, the Pliocene relic Vavilovia formosa (Fabeae: Fabaceae). Those investigations are little known to the scientific community, although, in fact, the priority right for integrated research into this plant belongs to VIR. As a result of the cycle of studies, the first ideas about the biology and ecology of the species, the manner of its reproduction, its intraspecific diversity, the degree of crossability with other members of the tribe, its karyotype and anatomy were developed. The plants of V. formosa are not reproduced ex situ and their germplasm is absent in the world’s gene banks. Therefore, collecting V. formosa plants in their hard-to-reach habitats in the mountains is always crucial for research purposes, so a number of collecting expeditions were launched to the Greater Caucasus. The data thus obtained are discussed in the context of modern achievements in world science regarding this species.

The genome organization and gene content of plastome (plastid genome) are highly conserved among most flowering plant species. Plastome variation (in size and gene order) is rare in photosynthetic species but size variation, rearrangements and gene/intron losses is attributed to groups of seed plants. Fabaceae (legume family), in particular the subfamily Papilionoideae and the inverted repeat lacking clade (IRLC), a largest legume lineage, display the most dramatic and structural change which providing an excellent model for understanding of mechanisms of genomic evolution. The IRLC comprises 52 genera and ca 4000 species divided into seven tribes. In present study, we have sampled several representatives from each tribe across the IRLC from various herbaria and field. The ycf4 gene, which plays a role in regulating and assembly of photosystem I, is more variable in the tribe Fabeae than in other tribes. In certain species of Lathyrus, Pisum and Vavilovia, all belonging to Fabeae, the gene is either absent or a pseudogene. Our study suggests that ycf4 gene has undergone positive selection. Furthermore, the rapid evolution of the gene is locus and lineage specific and is not a shared character of the IRLC in legumes.

Comparative sequence analysis of symbiotic genes (nodA, nodC, nodD, nifH), which are elements of accessory component of the rhizobial genome, demonstrated that the strains of Rhizobium leguminosarum bv. viciae, isolated from the nodules of a relic legume, Vavilovia formosa, the closest relative of hypothetical common ancestor of the tribe Fabeae, represented a group separated from the strains of R. leguminosarum bv. viciae, isolated from other representatives of this tribe (Vicia, Lathyrus, Pisum, Lens). No isolation was observed relative to the genes representing the core component of the rhizobial genome (16S rDNA, ITS, glnII) or relative to host specificity of the rhizobia. The data obtained suggest that sequence divergence of symbiotic genes marks the initial stage of sympatric speciation, which can be classified as the isolation of the relic “vaviloviae” symbiotype, a possible evolutionary precursor of the “viciae” biotype.

Rhizobia are α- and s-proteobacteria that associate with legumes in symbiosis to fix atmospheric nitrogen. The chemical communication between roots and rhizobia begins in the rhizosphere. Using signature-tagged-Tn5 mutagenesis (STM) we performed a genome-wide screening for Ensifer meliloti genes that participate in colonizing the rhizospheres of alfalfa and other legumes. The analysis of ca. 6,000 mutants indicated that genes relevant for rhizosphere colonization account for nearly 2% of the rhizobial genome and that most (ca. 80%) are chromosomally located, pointing to the relevance and ancestral origin of the bacterial ability to colonize plant roots. The identified genes were related to metabolic functions, transcription, signal transduction, and motility/chemotaxis among other categories; with several ORFs of yet-unknown function. Most remarkably, we identified a subset of genes that impacted more severely the colonization of the roots of alfalfa than of pea. Further analyses using other plant species revealed that such early differential phenotype could be extended to other members of the Trifoliae tribe (Trigonella, Trifolium), but not the Fabeae and Phaseoleae tribes. The results suggest that consolidation of E. meliloti into its current symbiotic state should have occurred in a rhizobacterium that had already been adapted to rhizospheres of the Trifoliae tribe.

The Abyssinian pea (Pisum abyssinicum A. Br.), concerned in this review, is known from Ethiopia and Yemen, where it is cultivated along with the common pea (Pisum sativum L. subsp. sativum). The continuously reproduced notion of its possible spontaneous occurrence in the wild ascends to suppositions made in the XIX century and is not based on any actual data. P. abyssinicum is of practical interest owing to its extra early ripening and resistance to bacterial blight. Morphologically it is very similar to P. sativum but its crossability with it is bad as either seed or pollen parent. Traditionally this reproductive barrier was associated with karyological differences. The Abyssinian pea karyotype is variable as 1–2 reciprocal translocations were reported. At the same time there are accessions not differing from the standard karyotype of P. sativum with respect to reciprocal translocations, yet their crossability with the latter is very low and the pollen fertility of F1 and F2 hybrids is lowered. Data were reported on influence of the region of Linkage Group III, containing a gene known to participate in the conflict of nucleus and plastids in remote crosses of peas, on the pollen fertility of hybrids with abyssinian pea. With their karyological variability, the known accessions of the Abyssinian pea are very close to each other genetically, as they diverged just about 4000 years ago. The presence of alleles of molecular markers common with Pisum fulvum Sibth. et Smith on the one hand and P. sativum L. subsp. elatius (Bieb.) Schmalh. on the other hand evidences in favour of an old hypotheses by L.I. Govorov that the Abyssinian pea originated from their spontaneous hybrid. This spontaneous cross may have taken place under cultivation, in Yemen or Afar Depression. A representative of P. sativum subsp. elatius was revealed, the F1 hybrids of which with the Abyssinian pea as a seed parent had fully fertile pollen. P. abyssinicum× P. fulvum crosses provide the best hybrid seed outcome among remote crosses conducted, so that P. abyssinicum can be used as a ‘bridge’ for gene introgression from P. fulvum to P. sativum. Rather a high evel of reproductive isolation of the Abyssinian pea from other representatives of the genus conforms the biological species concept, however the disposition of P. abyssinicum accessions as a small cluster among accessions of P. sativum subsp. elatius on molecular phylogeny reconstructions violates the phylogenetic species concept. Most authors assume the Abyssinian pea as a species, Pisum abyssinicum, some as a subspecies, P. sativum subsp. abyssinicum (A. Br.) Berger. Perhaps it would be most correct to consider it as a hybridogenic species. Because of the recent subsuming of the genus Pisum L. into the genus Lathyrus and with respect to the existing name Lathyrus abyssinicus A. Br. (a synonym of L. sativus L.), the Abyssinian pea is given a new name Lathyrus schaeferi (A. Braun) Kosterin nomen novum pro Pisum abyssinicum A. Braun), in honour of Hanno Schaefer, who substantiated the revision of tribe Fabeae by molecular reconstruction of its phylogeny. New combinations of Lathyrus sectio Pisum (L.) Kosterin combinatio nova and Lathurus fulvus (Sibthrop et Smith) Kosterin combinatio nova are proposed.

Twenty-two rhizobia strains isolated from three distinct populations (North Ossetia, Dagestan, and Armenia) of a relict legume Vavilovia formosa were analysed to determine their position within Rhizobium leguminosarum biovar viciae (Rlv). These bacteria are described as symbionts of four plant genera Pisum, Vicia, Lathyrus, and Lens from the Fabeae tribe, of which Vavilovia is considered to be closest to its last common ancestor (LCA). In contrast to biovar viciae, bacteria from Rhizobium leguminosarum biovar trifolii (Rlt) inoculate plants from the Trifolieae tribe. Comparison of house-keeping (hkg: 16S rRNA, glnII, gltA, and dnaK) and symbiotic (sym: nodA, nodC, nodD, and nifH) genes of the symbionts of V. formosa with those of other Rlv and Rlt strains reveals a significant group separation, which was most pronounced for sym genes. A remarkable feature of the strains isolated from V. formosa was the presence of the nodX gene, which was commonly found in Rlv strains isolated from Afghanistan pea genotypes. Tube testing of different strains on nine plant species, including all genera from the Fabeae tribe, demonstrated that the strains from V. formosa nodulated the same cross inoculation group as the other Rlv strains. Comparison of nucleotide similarity in sym genes suggested that their diversification within sym-biotypes of Rlv was elicited by host plants. Contrariwise, that of hkg genes could be caused by either local adaptation to soil niches or by genetic drift. Long-term ecological isolation, genetic separation, and the ancestral position of V. formosa suggested that symbionts of V. formosa could be responsible for preserving ancestral genotypes of the Rlv biovar.

Beautiful Vavilovia [Vavilovia formosa (Stev.) Fed.] is a perennial legume of great importance for the evolution and taxonomy of the tribe Fabeae Rchb. The abundant data on its collection sites on the Caucasus Mountains, made during the past two centuries, were collated and analysed. The studied area covers the mountain ranges of both the Greater and Lesser Caucasus in Russian Federation, Georgia, Armenia and Azerbaijan, except the ranges in north-eastern and eastern Turkey and north-western Iran. The presented data are the results of an analysis of the herbarium collections of various institutions and available literature resources, providing novel information about 110 collection points. The analysed data allowed to specify the borders of the area in the region, as well as describe the features of the high-altitude distribution of V. formosa within the studied area, revealing the lower and upper altitude ranges as between 2021 and 3500 m above sea level. The results also indicate a reduction of the number of its populations, as well as the necessity and urgency of monitoring and protecting all the known locations of this highly endangered species.

Lack of complete genomic information concerning Vicia sepium (Fabaceae: Fabeae) precludes investigations of evolution and populational diversity of this perennial high-protein forage plant suitable for cultivation in extreme conditions. Here, we present the complete and annotated chloroplast genome of this important wild resource plant. V. sepium chloroplast genome includes 76 protein-coding genes, 29 tRNA genes, 4 rRNA genes, and 1 pseudogene. Its 124,095 bp sequence has a loss of one inverted repeat (IR). The GC content of the whole genome, the protein-coding, intron, tRNA, rRNA, and intergenic spacer regions was 35.0%, 36.7%, 34.6%, 52.3%, 54.2%, and 29.2%, respectively. Comparative analyses with plastids from related genera belonging to Fabeae demonstrated that the greatest variation in the V. sepium genome length occurred in protein-coding regions. In these regions, some genes and introns were lost or gained; for example, ycf4, clpP intron, and rpl16 intron deletions and rpl20 and ORF292 insertions were observed. Twelve highly divergent regions, 66 simple sequence repeats (SSRs) and 27 repeat sequences were also found in these regions. Detailed evolutionary rate analysis of protein-coding genes showed that Vicia species exhibit additional interesting characteristics including positive selection of ccsA, clpP, rpl32, rpl33, rpoC1, rps15, rps2, rps4, and rps7, and the evolutionary rates of atpA, accD, and rps2 in Vicia are significantly accelerated. These genes are important candidate genes for understanding the evolutionary strategies of Vicia and other genera in Fabeae. The phylogenetic analysis showed that Vicia and Lens are included in the same clade and that Vicia is paraphyletic. These results provide evidence regarding the evolutionary history of the chloroplast genome.

The genus Vicia L., one of the earliest domesticated plant genera, is a member of the legume tribe Fabeae of the subfamily Papilionoideae (Fabaceae). The taxonomic history of this genus is extensive and controversial, which has hindered the development of taxonomic procedures and made it difficult to identify and share these economically important crop resources. Species identification through DNA barcoding is a valuable taxonomic classification tool. In this study, four DNA barcodes (ITS2, matK, rbcL and psbA-trnH) were evaluated on 110 samples that represented 34 taxonomically best-known species in the Vicia genus. Topologies of the phylogenetic trees based on an individual locus were similar. Individual locus-based analyses could not discriminate closely related Vicia species. We proposed a concatenated data approach to increase the resolving power of ITS2. The DNA barcodes matK, psbA-trnH and rbcL were used as an additional tool for phylogenetic analysis. Among the four barcodes, three-barcode combinations that included psbA-trnH with any two of the other barcodes (ITS2, matK or rbcL) provided the best discrimination among Vicia species. Species discrimination was assessed with bootstrap values and considered successful only when all the conspecific individuals formed a single clade. Through sequencing of these barcodes from additional Vicia accessions, 17 of the 34 known Vicia species could be identified with varying levels of confidence. From our analyses, the combined barcoding markers are useful in the early diagnosis of targeted Vicia species and can provide essential baseline data for conservation strategies, as well as guidance in assembling germplasm collections.

In most eukaryotes, centromere is determined by the presence of the centromere-specific histone variant CenH3. Two types of chromosome morphology are generally recognized with respect to centromere organization. Monocentric chromosomes possess a single CenH3-containing domain in primary constriction, whereas holocentric chromosomes lack the primary constriction and display dispersed distribution of CenH3. Recently, metapolycentric chromosomes have been reported in Pisum sativum, representing an intermediate type of centromere organization characterized by multiple CenH3-containing domains distributed across large parts of chromosomes that still form a single constriction. In this work, we show that this type of centromere is also found in other Pisum and closely related Lathyrus species, whereas Vicia and Lens genera, which belong to the same legume tribe Fabeae, possess only monocentric chromosomes. We observed extensive variability in the size of primary constriction and the arrangement of CenH3 domains both between and within individual Pisum and Lathyrus species, with no obvious correlation to genome or chromosome size. Search for CenH3 gene sequences revealed two paralogous variants, CenH3-1 and CenH3-2, which originated from a duplication event in the common ancestor of Fabeae species. The CenH3-1 gene was subsequently lost or silenced in the lineage leading to Vicia and Lens, whereas both genes are retained in Pisum and Lathyrus. Both of these genes appear to have evolved under purifying selection and produce functional CenH3 proteins which are fully colocalized. The findings described here provide the first evidence for a highly dynamic centromere structure within a group of closely related species, challenging previous concepts of centromere evolution.

The temperate and herbaceous genus Vicia L. is a member of the legume tribe Fabeae of the subfamily Papilionoideae. The genus Vicia comprises 166 annual or perennial species distributed mainly in Europe, Asia, and North America, but also extending to the temperate regions of South America and tropical Africa. The use of simple sequence repeat (SSR) markers for Vicia species has not been investigated as extensively as for other crop species. In this study, we assessed the potential for cross-species amplification of cDNA microsatellite markers developed from common vetch (Vicia sativa subsp. sativa). For cross-species amplification of the SSRs, amplification was carried out with genomic DNA isolated from two to eight accessions of 22 different Vicia species. For individual species or subspecies, the transferability rates ranged from 33% for V. ervilia to 82% for V. sativa subsp. nigra with an average rate of 52.0%. Because the rate of successful SSR marker amplification generally correlates with genetic distance, these SSR markers are potentially useful for analyzing genetic relationships between or within Vicia species.

The nutritional characteristics of seed proteins of 50 Spanish wild taxa of Lathyrus, Lens, Pisum and Vicia have been compared. The highest average protein richness and the in vitro protein digestibility have been observed in the genus Vicia and Lens, respectively, whereas the genus Pisum showed the lowest protein-digestibility corrected amino acid score. Using the K-means algorithm three clearly distinguished groups of taxa have been established in relation to their essential amino acid contents, protein richness, digestibility and nutritional parameters. The most adequate protein profile was observed in the taxa of group 1. This group includes four taxa of genus Lathyrus and nine taxa of genus Vicia. It should be noted that seven of the thirteen taxa included in this group have never been used as crops. © 2014 Elsevier Ltd. All rights reserved., This work was financed by Grant AGR-711 from Junta de Andalucía (Spain). Thanks are due to María Dolores García-Contreras for technical assistance.

Vavilovia formosa is a relict leguminous plant growing in hard-to-reach habitats in the rocky highlands of the Caucasus and Middle East, and it is considered as the putative closest living relative of the last common ancestor (LCA) of the Fabeae tribe. Symbionts of Vavilovia belonging to Rhizobium leguminosarum bv. viciae compose a discrete group that differs from the other strains, especially in the nucleotide sequences of the symbiotically specialised (sym) genes. Comparison of the genomes of Vavilovia strains with the reference group composed of R. leguminosarum bv. viciae strains isolated from Pisum and Vicia demonstrated that the vavilovia strains have a set of genomic features, probably indicating the important stages of microevolution of the symbiotic system. Specifically, symbionts of Vavilovia (considered as an ancestral group) demonstrated a scattered arrangement of sym genes (&gt, 90 kb cluster on pSym), with the location of nodT gene outside of the other nod operons, the presence of nodX and fixW, and the absence of chromosomal fixNOPQ copies. In contrast, the reference (derived) group harboured sym genes as a compact cluster (&lt, 60 kb) on a single pSym, lacking nodX and fixW, with nodT between nodN and nodO, and possessing chromosomal fixNOPQ copies. The TOM strain, obtained from nodules of the primitive &ldquo, Afghan&rdquo, peas, occupied an intermediate position because it has the chromosomal fixNOPQ copy, while the other features, the most important of which is presence of nodX and fixW, were similar to the Vavilovia strains. We suggest that genome evolution from the ancestral to the derived R. leguminosarum bv. viciae groups follows the &ldquo, gain-and-loss of sym genes&rdquo, and the &ldquo, compaction of sym cluster&rdquo, strategies, which are common for the macro-evolutionary and micro-evolutionary processes. The revealed genomic features are in concordance with a relict status of the vavilovia strains, indicating that V. formosa coexists with ancestral microsymbionts, which are presumably close to the LCA of R. leguminosarum bv. viciae.

Vavilovia formosa is a relict, endangered species from the highlands of the Caucasus and the Near East. Described in 1812, it has had an uncertain status and was finally recognized as a separate genus of tribe Fabeae (Fabaceae). Our informal international group was established in 2007 to revive the interest in this species as it had been seriously neglected for decades. Here, we provide an overview of the accumulated knowledge on V. formosa and present the results of the most recent multidisciplinary research. Three expeditions were made to two locations in Armenia in 2009, providing the material for anatomical, morphological, chemical and molecular analysis. Unlike previous attempts, ex situ conservation in Yerevan and in vitro propagation, important for potential interspecific hybridization, were successful. Molecular tools were used to clarify the taxonomic position of V. formosa, often considered the closest to the extinct ancestor of the whole tribe. The analysis of four informative regions of plastid and nuclear DNA showed that V. formosa belongs to the same clade as Lathyrus and Pisum, with a distinct status. Preservation and maintenance of V. formosa remains the only basis for further development of all other scientific aspects, especially breeding and uses in agronomy. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 172, 524–531.

Vavilovia formosa is one of five genera in tribe Fabeae, (Fabaceae, Leguminosae) with close phylogenetic relationships to Pisum. It grows in subalpine and alpine levels in Armenia, Azerbaijan, Georgia, Iran, Iraq, Lebanon, Russia and Turkey and is recognized as an endangered and protected plant. This study was conducted to reveal its intraspecific variability, as well as to predict the past, extant and future species distribution range. We analysed 51 accessions with common phylogenetic markers (trnF-trnL, trnS-trnG, matK, rbcL, psbA-trnH and ITS). These represent in total up to 2551 bp of chloroplast and 664 bp of nuclear sequences per sample. Two populations from Turkey and Armenia were analysed for genetic diversity by AFLP. Leaf morphometry was conducted on 1457 leaflets from 43 specimens. Extracted bioclimatic parameters were used for niche-modelling approach. Analysis of cpDNA revealed two haplotypes, 12 samples from Armenia, Daghestan, Nakhichevan and Iran belonged to H1 group, while 39 samples of all Turkish and part of Armenian were in H2 group. The mean intrapopulation diversity based on AFLP was low (H E = 0.088) indicating limited outcrossing rate. A significantly positive correlation between geographical latitude and leaf area ( $$\rho$$ = 0.527, p

Chlorinated auxin (4-chloroindole-3-acetic acid, 4-Cl-IAA), a highly potent plant hormone, was once thought to be restricted to species of the tribe Fabeae within the Fabaceae, until we recently detected this hormone in the seeds of Medicago, Melilotus and Trifolium species. The absence of 4-Cl-IAA in the seeds of the cultivated species Cicer aeritinum from the Cicerae tribe, immediately basal to the Fabeae and Trifolieae tribes, suggested a single evolutionary origin of 4-Cl-IAA. Here, we provide a more robust phylogenetic placement of the ability to produce chlorinated auxin by screening key species spanning this evolutionary transition. We report no detectable level of 4-Cl-IAA in Cicer echinospermum (a wild relative of Cicer aeritinum) and 4 species (Galega officinalis, Parochetus communis, Astragalus propinquus and A. sinicus) from tribes or clades more basal or sister to the Cicerae tribe. We did detect 4-Cl-IAA in the dry seeds of four species from the genus Ononis that are either basal to the genera Medicago, Melilotus and Trigonella or basal to, but still within, the Fabeae and Trifolieae (ex. Parochetus) clades. We conclude that the single evolutionary origin of this hormone in seeds can be used as a phylogenetically informative trait within the Fabaceae.

The plastid genome retains several features from its cyanobacterial-like ancestor, one being the co-transcriptional organization of genes into operon-like structures. Some plastid operons have been identified but undoubtedly many more remain undiscovered. Here we utilize the highly variable plastome structure that exists within certain legumes of the inverted repeat lost clade (IRLC) to find conserved gene clusters. These plastomes exhibit an unusually high frequency of translocations and inversions. We analysed the plastomes of 23 legume species and identified 32 locally collinear blocks (LCBs), which are regions within the plastid genomes that occur in different orientation and/or order among the plastid genomes but are themselves free from internal rearrangements. Several represent gene clusters that have previously been recognized as plastid operons. It appears that the number of LCBs has reached saturation in our data set, suggesting that these LCBs are not random, but likely represent legume plastid operons protected from internal rearrangement by functional constraint. Some of the LCBs we identify, such as psbD/C/Z, are previously known plastid operons. Others, such as rpl32-ndhF-psbA-matK-rbcL-atpB-atpE, may represent novel polycistronic operons in legumes.

6 páginas; 6 Tablas; 3 Figuras, The benefits of polyphenols have been widely demonstrated in recent decades. In order to find new species with a high biological functionality, the antioxidant activity of the polyphenol extracts from seeds of 50 taxa of tribe Fabeae (Lathyrus, Lens, Pisum, and Vicia) from Spain has been studied. Considering the average concentration obtained from the data in the four genera of the Fabeae tribe, Pisum and Lathyrus show the highest average polyphenol concentration. The highest specific antioxidant activity as well as the antioxidant activity coefficient was observed in Pisum and Vicia. However, with respect to the total antioxidant activity, the highest average value was observed in Lathyrus and Pisum. The results obtained reveal that many of the wild taxa examined could be potential source of antioxidants., This work was financed by Grant AGR-711 from Junta de Andalucía (Spain).

Premise of the study In angiosperm seeds, the developing embryo acquires nutrients via a suspensor that typically undergoes programmed cell death (PCD) at the early cotyledon stage. However, in Leguminosae (the third largest angiosperm family), the suspensors can disappear at the heart-shaped stage (i.e., prior to the cotyledon stage) or still persist at the cotyledon stage. Here, in a comprehensive survey of legume suspensors and embryos, the variation and the evolutionary direction of timing of suspensor PCD in Leguminosae were characterized, and systematic implications were evaluated. Methods Suspensor development and morphology for 66 leguminous species from 49 genera, 21 tribes, and 3 subfamilies were comparatively studied using standard paraffin sectioning and light microscopy. Key results Three patterns of suspensor PCD were observed at the early cotyledon stage. (A) The suspensor persisted. (B) The suspensor separated from the wall of the embryo sac and persisted as a vestige at the radicle apex. (C) The suspensor disappeared completely, and the absorption of nutrients by embryo was carried out via a "contact zone" between the embryo and the endosperm. Pattern C of early suspensor PCD was found only in the tribe Fabeae. An ancestral character reconstruction revealed that the long-lived suspensors of pattern A represented a plesiomorphic condition in Leguminosae and that the suspensors of pattern C evolved only once in the common ancestor of Fabeae. Conclusions In Leguminosae, short-lived suspensors have thus evolved multiple times from long-lived suspensors. It remains largely unknown, however, how the embryo acquires nutrients after the early suspensor PCD.

The aims of the present study were (i) to compare the anatomical structures of roots from legume species belonging to the tribes Aeschynomeneae, Fabeae (syn. Vicieae), and Trifolieae (Papilionoideae); (ii) to characterize those developmental stages of roots that are most useful for comparative studies; (iii) to characterize root developmental patterns during their growth from primary to adult structures; and (iv) to identify developmental patterns that are typical for particular tribes within this plant group. To this end, serial transverse cuts of the main roots of 20 species belonging to the above-mentioned tribes were made from the root tip to the root collar. Vessel density, vessel diameter, secondary cortex area, and xylem area were quantified using appropriate software. Based on root ontogeny, four stages giving evidence for important developmental events were chosen based on which a comparison of the species-specific structures became possible. The first stage corresponds to the primary structure of a root. The second stage corresponds to the onset of cambium and phellogen division, when their first division products become differentiated. The third and fourth stages correspond to adult roots with a well-developed secondary structure. These developmental stages that allowed between-species comparison turned out to be useful characterising those patterns that best typify a particular tribe within the subfamily. Vessel density, vessel diameter, and the xylem transverse area were found to differ significantly between the tribes examined. Some of the analyzed morphological variables had a tribe-specific consistency, so that, together with other characteristics, they should be included in approaches to clarify systematic problems in the legume family.

The carbohydrate-binding sequences of the lectin genes from spring vetchling Lathyrus vernus (L.) Bernh., marsh vetchling L. palustris (L.), and Gmelin’s vetchling L. gmelinii (Fitsch) (Fabaceae) were determined. Computer-aided analysis revealed substantial differences between nucleotide and predicted amino acid sequences of the lectin gene regions examined in each of the three vetchling species tested. In the phylogenetic trees based on sequence similarity of carbohydrate-biding regions of legume lectins, the sequences examined formed a compact cluster with the lectin genes of the plants belonging to the tribe Fabeae. In each plant, L. vernus, L. palustris, and L. gmelinii, three different lectin-encoding genes were detected. Most of the substitutions were identified within the gene sequence responsible for coding the carbohydrate-binding protein regions. This finding may explain different affinity of these lectins to different carbohydrates, and as a consequence, can affect the plant host specificity upon development of symbiosis with rhizobium bacteria.

Summary: A considerable number of diverse ornamental forms of Lathyrus odoratus exist which require careful conservation if they are not to be lost. Other ornamental Lathyrus species may have potential for increasing their diversity. A seedbank has been established in the United Kingdom to conserve this diversity and make the material readily available to researchers and growers throughout the world. Conventional hybridisation provides an opportunity for the existing diversity in L. odoratus to be extended. Opportunities also exist to create improved decorative forms and new colours in some other species through intra-specifi c hybridisation. Inter-specifi c hybridisation within the genus is in its infancy but early results suggest exciting improvements might be introduced by this method. Such work might also provide benefi ts for comparative genomics in the tribe Fabeae.

The tribeFabeae(formerlyVicieae) contains some of humanity's most important grain legume crops, namelyLathyrus(grass pea/sweet pea/chickling vetches; about 160 species);Lens(lentils; 4 species);Pisum(peas; 3 species);Vicia(vetches; about 140 species); and the monotypic genusVavilovia.Reconstructing the phylogenetic relationships within this group is essential for understanding the origin and diversification of these crops. Our study, based on molecular data, has positionedPisumgenetically betweenViciaandLathyrusand shows it to be closely allied toVavilovia.A study of phylogeography, using a combination of plastid and nuclear markers, suggested that wild pea spread from its centre of origin, the Middle East, eastwards to the Caucasus, Iran and Afghanistan, and westwards to the Mediterranean. To allow for direct data comparison, we utilized model-based Bayesian Analysis of Population structure (BAPS) software on 4429Pisumaccessions from three large world germplasm collections that include both wild and domesticated pea analyzed by retrotransposon-based markers. An analysis of genetic diversity identified separate clusters containing wild material, distinguishingPisum fulvum,P. elatiusandP. abyssinicum, supporting the view of separate species or subspecies. Moreover, accessions of domesticated peas of Afghan, Ethiopian and Chinese origin were distinguished. In addition to revealing the genetic relationships, these results also provided insight into geographical and phylogenetic partitioning of genetic diversity. This study provides the framework for defining globalPisumgermplasm diversity as well as suggesting a model for the domestication of the cultivated species. These findings, together with gene-based sequence analysis, show that although introgression from wild species has been common throughout pea domestication, much of the diversity still resides in wild material and could be used further in breeding. Moreover, although existing collections contain over 10,000 pea accessions, effort should be directed towards collecting more wild material in order to preserve the genetic diversity of the species.

The phylogenetic status of the monotypic genus Vavilovia was studied using nrDNA ITS and cpDNA trnL-F and trnS-G regions. The results from the analysis of each dataset and the combined dataset, revealed that Vavilovia is closely related to Pisum, forming a group that is sister to Lathyrus. The molecular data and some morphological and biological characteristics strongly indicate that Vavilovia should be subsumed under Pisum, as Pisum formosum.

Nodules in the family Leguminosae come in many different shapes and forms, depending partly on the host that bears them. This review focuses on the peripheral tissues that surround the infected tissues of four anatomically distinct classes of nodules: nodules with indeterminate meristems (from the Trifolieae and Fabeae tribes); desmodioid nodules with determinate meristems (from the Phaseoleae and Loteae tribes); aeschynomenoid nodules ( Arachis hypogaea L., peanut); and lupinoid nodules ( Lupinus sp. L., lupine). I have especially stressed the importance of the three-dimensionality of the organ, because not all nodules display a radial symmetry as it is often assumed. The goal of this review is to provide a strong base of nodule structure so that forthcoming molecular studies can integrate this information into their approach.

The approximately 27 New World species of Vicia (tribe Fabeae, family Leguminosae) were classified into four stylar type groups as follows: (1) a laterally compressed and evenly hairy stylar type (Le-type) group, (2) a dorsiventrally compressed and abaxially tufted hairy stylar type (Dabt-type) group, (3) a dorsiventrally compressed and evenly hairy stylar type (De-type) group, and (4) V. leuncophaea that is characterized by an arcuate style with a dense ring of stylar hairs at a considerable distance from the stigma. In the present study, the stylar distinctions among the groups were confirmed by morphological and anatomical studies on the stylar characters of representative species of the groups. The phylogenetic positions of these groups were then assessed using molecular phylogenetic analysis based on sequences from the nuclear ribosomal DNA (nrDNA) internal transcribed spacer (ITS) region of the representative species. The New World Le-type stylar group was revealed to be a sister group to t...

Morphological and geographic variation in two Lathyrus and two Vicia species complexes is reviewed. The following new combinations are proposed: Lathyrus nevadensis S. Wats. var. cusickii (S. Wats.) Broich comb. nov., Lathyrus lanszwertii Kellogg var. sandbergii (T. White) Broich comb. nov., Vicia ludoviciana Nutt. ex T. & G. var. leavenworthii (T. & G.) Broich comb. nov., and Vicia nigricans H. & A. var. gigantea (Hooker) Broich comb. nov.

The differential accumulation and elimination of repetitive DNA are key drivers of genome size variation in flowering plants, yet there have been few studies which have analysed how different types of repeats in related species contribute to genome size evolution within a phylogenetic context. This question is addressed here by conducting large-scale comparative analysis of repeats in 23 species from four genera of the monophyletic legume tribe Fabeae, representing a 7.6-fold variation in genome size. Phylogenetic analysis and genome size reconstruction revealed that this diversity arose from genome size expansions and contractions in different lineages during the evolution of Fabeae. Employing a combination of low-pass genome sequencing with novel bioinformatic approaches resulted in identification and quantification of repeats making up 55?83% of the investigated genomes. In turn, this enabled an analysis of how each major repeat type contributed to the genome size variation encountered. Differential accumulation of repetitive DNA was found to account for 85% of the genome size differences between the species, and most (57%) of this variation was found to be driven by a single lineage of Ty3/gypsy LTR-retrotransposons, the Ogre elements. Although the amounts of several other lineages of LTR-retrotransposons and the total amount of satellite DNA were also positively correlated with genome size, their contributions to genome size variation were much smaller (up to 6%). Repeat analysis within a phylogenetic framework also revealed profound differences in the extent of sequence conservation between different repeat types across Fabeae. In addition to these findings, the study has provided a proof of concept for the approach combining recent developments in sequencing and bioinformatics to perform comparative analyses of repetitive DNAs in a large number of non-model species without the need to assemble their genomes.

Lathyrus (Leguminosae; Papilionoideae) is the largest genus in tribe Fabeae and exhibits an intriguing extratropical distribution. We studied the systematics and biogeography of Lathyrus using sequence data, from accessions representing 53 species, for the internal transcribed spacer plus 5.8S-coding region of nuclear ribosomal DNA as well as the trnL-F and trnS-G regions of chloroplast DNA. Our results generally supported recent morphology-based classifications, resolving clades corresponding to sections Lathyrus and Lathyrostylis, but question the monophyly of the large, widespread section Orobus sensu Asmussen and Liston. Sections Orobus, Aphaca, and Pratensis form a predominantly northern Eurasian-New World clade. Within this clade, the North American and eastern Eurasian species, including both Holarctic species (L. palustris and L. japonicus), form a transberingian clade of relatively recent origin and diversification. The South American Notolathyrus group is distant from this transberingian lineage and should be reinstated as a distinct section within the northern Eurasian-New World clade. The Notolathyrus lineage reached the New World most probably through long-distance dispersal from Eurasia. The remaining sections in the genus are centered on the Mediterranean region.

The present study reports the inflorescence ontogeny and morphology in tribe Fabeae (Fabaceae) addressing the evolutionary trends of selected inflorescence features in clade Lathyrus–Pisum–Vavilovia. In all three mentioned genera, the whole inflorescence in annual taxa comprises an open shoot bearing frondose leaves subtended by simple racemes. This shoot exhibits a pendulum symmetry which results from skewed position of leaves initiating at shoot apex. During floral initiation in a model species, i.e., Vicia cracca, numerous flowers are produced on these racemes but later most of them degrade and only a small portion (

Background: More than 60 species of the genus Lathyrus are distributed in Southwest Asia. It is the second largest genus of the tribe Fabeae, after Vicia, in the region (and in Iran with 23 species). In the regional Flora (Flora of Turkey, Flora Iranica and flora of Iran), the genus has been divided into 9-10 sections. Here we analyzed the phylogeny of Lathyrus and its relationship with Pisum based on plastid gene matK sequences. Objectives: The present study utilized several approaches including maximum parsimony, Bayesian and maximum likelihood methods to evaluate the monophyly and relationship within the genus Lathyrus, both at the sectional level and species level, mainly based on the taxa growing in Iran. Materials and Methods: A total of 52 accessions, representing 38 species of Lathyrus, three species of Pisum and four species of Vicia and Lens as out-groups, were analyzed for reconstructing the phylogenetic relationship using chloroplast gene matK sequences. Maximum parsimony, Bayesian and maximum likelihood methods were used to construct phylogenetic trees. Results: The present study indicated that Pisum was nested among Lathyrus species. Two members of the Lathyrus section, Clymenum (Lathyrus ochrus and L. Clymenum) with Pisum, formed a weakly supported clade as sister to the larger polytomy comprising the remainder of the Lathyrus species. Several sections of Lathyrus including Lathyrostylis, Lathyrus and Clymenum were monophyletic. Lathyrus roseus (of the monotypic section Orobon) were nested among the members of section Lathyrus. The newly taxon described species L. alamutensis, endemic to Iran, were nested among other species of Lathyrostylis. Linearicarpus, Orobus and Pratensis were not monophyletic sections. Pratensis and the monotypic section Aphaca were the closest taxa. In our analysis, L. Pratensis formed a sister group relationship with the Aphaca clade, not its own section. Conclusions: Shimodaira-Hasegawa (SH) test of the matK data set showed that all of the analyzed Lathyrus species formed their own clade and Pisum was sister to them. Furthermore, when we removed the two above-mentioned Lathyrus species, the analysis retrieved Pisum, as a well-supported clade being sister to the Lathyrus calde.

The first complete plastid genome (plastome) of the largest angiosperm genus, Astragalus, was sequenced for the Korean endangered endemic species A. mongholicus var. nakaianus. Its genome is relatively short (123,633 bp) because it lacks an Inverted Repeat (IR) region. It comprises 110 genes, including four unique rRNAs, 30 tRNAs, and 76 protein-coding genes. Similar to other closely related plastomes, rpl22 and rps16 are absent. The putative pseudogene with abnormal stop codons is atpE. This plastome has no additional inversions when compared with highly variable plastomes from IRLC tribes Fabeae and Trifolieae. Our phylogenetic analysis confirms the non-monophyly of Galegeae.

International audience; Main conclusion Vavilovia formosa (Stev.) Fed. is a scientifically valuable common ancestor of the plant tribe Fabeae and also important in breeding and agronomy studies of the cultivated Fabeae, but it is close to extinction. A concerted academic and geovernmental effort is needed to save it. Abstract Since 2007, an informal international group of researchers on legumes has been working to increase awareness of Vavilovia formosa (Stev.) Fed., a relict and endangered wild-land relative to crop plant species. A majority of the modern botanical classifications place it within the tribe Fabeae, together with the genera vetchling (Lathyrus L.), lentil (Lens Mill.), pea (Pisum L.) and vetch (Vicia L.). V. formosa is encountered at altitudes from 1,500 m up to 3,500 m in Armenia, Azerbaijan, Georgia, Iran, Iraq, Lebanon, Russia, Syria and Turkey. This species may be of extraordinary importance for broadening current scientific knowledge on legume evolution and taxonomy because of its proximity to the hypothetical common ancestor of the tribe Fabeae, as well as for breeding and agronomy of the cultivated Fabeae species due to its perenniality and stress resistance. All this may be feasible only if a concerted and long-term conservation strategy is established and carried out by both academic and geovernmental authorities. The existing populations of V. formosa are in serious danger of extinction. The main threats are domestic and wild animal grazing, foraging, and early frosts in late summer. A long-term strategy to save V. formosa from extinction and to sustain its use in both basic and applied research comprises much improved in situ preservation, greater efforts for an ex situ conservation, and novel approaches of in vitro propagation.

In this study, the pollen morphology of 11 taxa belonging to Atossa (Alef.) Asch. & Graebner, Hypechusa (Alef.) Asch. & Graebner, Peregrinae Kupicha, Wiggersia (Alef.) Maxted, Vicia L. and Narbonensis (Radzhi) Maxted sections of the genus Vicia L. subgenus Vicia (Fabeae, Fabaceae) naturally growing in Turkey has been studied using Light Microscopy (LM) and Scanning Electron Microscopy (SEM) to evaluate the taxonomic relevance of pollen characters. Twelve morphometric characters are analysed with one-way analysis of variance and Tukey's honestly significant difference test for multiple comparisons. Of the taxa studied V. narbonensis var. narbonensis (sect. Narbonensis) has the largest pollen grains (P = 51.98 ?m × E = 30.52 ?m) and V. lathyroides (sect. Wiggersia) has the smallest pollen grains (P = 27.71 ?m × E = 20.14 ?m). The pollen grains are subprolate to perprolate (P/E = 1.16-2.11), but the prolate shape occurs in the majority of the taxa. The regular pollen grains of all taxa are trizonocolporate, isopolar, and released in monads. Ornamentation of the mesocolpium is psilate-perforate in V. lathyroides (sect. Wiggersia), reticulate-rugulate in V. narbonensis var. narbonensis (sect. Narbonensis), (micro)reticulate in V. sericocarpa var. sericocarpa (sect. Hypechusa), V. sativa subsp. sativa (sect. Vicia) and V. grandiflora var. grandiflora (sect. Vicia), and reticulate-perforate in the remaining taxa. The apocolpium and colpus area are psilate or perforate in all taxa except V. sericocarpa var. sericocarpa (sect. Hypechusa) and V. sativa subsp. sativa (sect. Vicia), which exhibit the obscurely reticulate-perforate pattern. Several palynological features have taxonomic importance in sectional level: polar axis, equatorial diameter, pollen shape (P/E ratio), colpus length, colpus width, size of pori, porus length/width ratio, lumina diameter, muri thickness and ornamentation. The results also indicate that pollen characters can be useful in distinguishing the examined taxa. © 2013 Springer-Verlag Wien.

Beautiful vavilovia, the closest species to the common now extinct ancestor of the whole tribe Fabeae holds significant taxonomical interest and also for breeding within this group of species, which includes the most cultivated leguminous pulses in the world. In spite of this, vavilovia has attracted very scarce research to date and is in danger of complete extinction. Thus, as a part of the research carried out by an informal international group of researchers from various countries, we report here various experiments for the development and exploitation of a range of biotechnology tools for vavilovia, ranging from standard in vitro propagation, to plant regeneration from explant-derived callus, and also from protoplasts. Plants were successfully recovered following propagation from nodes, and by regeneration through organogenesis from callus derived from internodes (which provided the best responses) and leaves. Also, protoplasts were isolated from leaves and stems from in vitro shoots and from callus derived from these two explants, with the latter undergoing sustained division. Subsequently, protoplasts isolated from internode callus proliferated and also underwent organogenesis coupled with whole plant recovery at a low frequency, while protoplasts from leaf callus origin followed both organogenesis and embryogenesis simultaneously but failed to yield viable plants. Flow cytometry assessments permitted to ascertain the genetic fidelity of both propagated and regenerated plants irrespectively of the source tissue from which they were derived (i.e., either callus from explants or from protoplasts). Finally, flow cytometry also permitted us to provide the first record on the relative nuclear DNA content and genome size for Vavilovia formosa.

Phylogenetic analysis of 330 plastid matK gene sequences, representing 235 genera from 37 of 39 tribes, and four outgroup taxa from eurosids I supports many well-resolved subclades within the Leguminosae. These results are generally consistent with those derived from other plastid sequence data (rbcL and trnL), but show greater resolution and clade support overall. In particular, the monophyly of subfamily Papilionoideae and at least seven major subclades are well-supported by bootstrap and Bayesian credibility values. These subclades are informally recognized as the Cladrastis clade, genistoid sensu lato, dalbergioid sensu lato, mirbelioid, millettioid, and robinioid clades, and the inverted-repeat-lacking clade (IRLC). The genistoid clade is expanded to include genera such as Poecilanthe, Cyclolobium, Bowdichia, and Diplotropis and thus contains the vast majority of papilionoids known to produce quinolizidine alkaloids. The dalbergioid clade is expanded to include the tribe Amorpheae. The mirbelioids include the tribes Bossiaeeae and Mirbelieae, with Hypocalypteae as its sister group. The millettioids comprise two major subclades that roughly correspond to the tribes Millettieae and Phaseoleae and represent the only major papilionoid clade marked by a macromorphological apomorphy, pseudoracemose inflorescences. The robinioids are expanded to include Sesbania and members of the tribe Loteae. The IRLC, the most species-rich subclade, is sister to the robinioids. Analysis of the matK data consistently resolves but modestly supports a clade comprising papilionoid taxa that accumulate canavanine in the seeds. This suggests a single origin for the biosynthesis of this most commonly produced of the nonprotein amino acids in legumes.

Vavilovia (Vavilovia Fed.) is one of the five genera in tribe Fabeae and consists of only one species, ‘beautiful’ vavilovia (Vavilovia formosa (Stev.) Fed.). The main centre of distribution is the Central and Eastern Caucasus, with a disjunct distribution among high alpine areas in the region, extending as far as West Turkey, Lebanon and Iran. In Armenia, in situ studies on Vavilovia started in the late 1930s. In July and August 2009, three expeditions were conducted to two locations: two to the Ughtasar Mountain and one to the Geghama Mountains. The first expedition to Ughtasar resulted in fresh plant collections and soil analysis for one of the sites. The expedition to Geghama established the existence of Vavilovia in the region of Lake Aknalitch. The second expedition to Ughtasar provided immature fruits and seeds. Collected plant material was transplanted into the Flora and Vegetation of Armenia plot of the Yerevan Botanic Garden established in 1940. Today, along with other plants the plot contains more than 200 species of wild relatives of cultural plants from 130 genera, including indiginous species of tribe Fabeae such as Vavilovia. The transplanted plants will continue to be monitored to see if the plants go on to successfully flower and set seed or whether further sites, possibly at higher altitudes might need to be tested to meet the long term conservation requirements of this iconic legume. These co-ordinated efforts provide a good example of an ex situ conservation strategy for Vavilovia formosa, which, if successful will improve access and utility for the whole legume research community.

Tendrils are contact-sensitive, filamentous organs that permit climbing plants to tether to their taller neighbors. Tendrilled legume species are grown as field crops, where the tendrils contribute to the physical support of the crop prior to harvest. The homeotic tendril-less (tl) mutation in garden pea (Pisum sativum), identified almost a century ago, transforms tendrils into leaflets. In this study, we used a systematic marker screen of fast neutron–generated tl deletion mutants to identify Tl as a Class I homeodomain leucine zipper (HDZIP) transcription factor. We confirmed the tendril-less phenotype as loss of function by targeting induced local lesions in genomes (TILLING) in garden pea and by analysis of the tendril-less phenotype of the t mutant in sweet pea (Lathyrus odoratus). The conversion of tendrils into leaflets in both mutants demonstrates that the pea tendril is a modified leaflet, inhibited from completing laminar development by Tl. We provide evidence to show that lamina inhibition requires Unifoliata/LEAFY-mediated Tl expression in organs emerging in the distal region of the leaf primordium. Phylogenetic analyses show that Tl is an unusual Class I HDZIP protein and that tendrils evolved either once or twice in Papilionoid legumes. We suggest that tendrils arose in the Fabeae clade of Papilionoid legumes through acquisition of the Tl gene.

The sphingoid long-chain base (LCB) composition of glucosylceramides was characterized in 31 species of Fabaceae including the model legumes Lotus japonicus and Medicago truncatula. With the exception of Lupinus texensis L, the 8-trans/cis-unsaturated isomers of 4-hydroxy-8-sphingenines [i.e., t18:1 (8t) plus t18:1 (8c)] were the major components in each species. In tribe Fabeae, each species from four genera--Pisum, Lathyrus, Lens, and Vicia--showed that more than 50% of dihydroxy sphingoid LCBs are 8-sphingenines [i.e., d18:1 (8t) plus d18:1 (8c)]. These results suggest that the sphingoid LCB composition of glucosylceramides reflects the phylogenetic relationships within the Fabeae.

A new species of Lathyrus is described. This species occurs in rocky fields, in a restricted protected area from Southern Brazil. Lathyrus ibicuiensis resembles L. linearifolius in having simple tendrils, but differs in ovate to lanceolate stipules, by ramified branches, and by elliptic, oblong to rarely obovate leaflets, as well as in its geographic distribution. A description and illustration are provided together with a key for identification of similar species occurring in Southern Brazil.

Tribe Fabeae consists of five genera, Lathyrus (160 spp.), Lens (4–6 spp.), Pisum (2–3 spp.), Vavilovia (monotypic), and Vicia (160 spp.), and shows a diversity in stylar features. At least six different stylar types are known in the tribe. In order to reclassify the tribe at the rank of genus, we tried to discover apomorphies in stylar features using a molecular phylogenetic study. We surveyed internal transcribed spacer (ITS) sequences of nuclear ribosomal DNA of representative species, selected from each group having different types of styles in the tribe. We paid particular attention in sampling to members of Vicia section Vicilla, as stylar features are heterogeneous within this section. Consequently, our sample set included 15 species of section Vicilla, 23 species of other Fabeae, and two species of Trifolieae, which were used as a sister group of Fabeae. Based on our analysis, we found that a laterally compressed style and an abaxially tufted hairy style would be advanced against a dorsiventrally compressed style and an evenly hairy style, respectively, in genus Vicia. The species group, which shares the latter apomorphy, is composed of 56 species and was dispersed into 11 sections of two subgenera in the recent system of genus Vicia. We consider future revision of Fabeae should treat this species group as a single higher taxon.

An antiserum specific for the legumin and vicilin of Vicia faba was used to examine extracts of seeds of taxa of the Fabeae and Trifolieae for the presence of related storage proteins, Proteins related to legumin were found to be widely distributed, indicating considerable conservation of the genetic information for this protein. Only Pisum sativum contained a protein immunochemically identical with the vicilin of V. faba; the equivalent proteins of all other genera tested here were immunochemically different from vicilin.

Fabeae legumes such as pea and faba bean form symbiotic nodules with a large diversity of soil Rhizobium leguminosarum symbiovar viciae (Rlv) bacteria. However, bacteria competitive to form root nodules (CFN) are generally not the most efficient to fix dinitrogen, resulting in a decrease in legume crop yields. Here, we investigate differential selection by host plants on the diversity of Rlv. A large collection of Rlv was collected by nodule trapping with pea and faba bean from soils at five European sites. Representative genomes were sequenced. In parallel, diversity and abundance of Rlv were estimated directly in these soils using metabarcoding. The CFN of isolates was measured with both legume hosts. Pea/faba bean CFN were associated to Rlv genomic regions. Variations of bacterial pea and/or faba bean CFN explained the differential abundance of Rlv genotypes in pea and faba bean nodules. No evidence was found for genetic association between CFN and variations in the core genome, but variations in specific regions of the nod locus, as well as in other plasmid loci, were associated with differences in CFN. These findings shed light on the genetic control of CFN in Rlv and emphasise the importance of host plants in controlling Rhizobium diversity.

Legumes of the Fabeae tribe form nitrogen-fixing root nodules resulting from symbiotic interaction with the soil bacteria Rhizobium leguminosarum symbiovar viciae (Rlv). These bacteria are all potential symbionts of the Fabeae hosts but display variable partner choice when co-inoculated in mixture. Because partner choice and symbiotic nitrogen fixation mostly behave as genetically independent traits, the efficiency of symbiosis is often suboptimal when Fabeae legumes are exposed to natural Rlv populations present in soil. A core collection of 32 Rlv bacteria was constituted based on the genomic comparison of a collection of 121 genome sequences, representative of known worldwide diversity of Rlv. A variable part of the nodD gene sequence was used as a DNA barcode to discriminate and quantify each of the 32 bacteria in mixture. This core collection was co-inoculated on a panel of nine genetically diverse Pisum sativum, Vicia faba, and Lens culinaris genotypes. We estimated the relative Early Partner Choice (EPC) of the bacteria with the Fabeae hosts by DNA metabarcoding on the nodulated root systems. Comparative genomic analyses within the bacterial core collection identified molecular markers associated with host-dependent symbiotic partner choice. The results revealed emergent properties of rhizobial populations. They pave the way to identify genes related to important symbiotic traits operating at this level.

Background Some clover species, particularly Trifolium subterraneum, have previously been reported to have highly unusual plastomes, relative to closely related legumes, enlarged with many duplications, gene losses and the presence of DNA unique to Trifolium, which may represent horizontal transfer. In order to pinpoint the evolutionary origin of this phenomenon within the genus Trifolium, we sequenced and assembled the plastomes of eight additional Trifolium species widely sampled from across the genus. Results The Trifolium plastomes fell into two groups: those of Trifolium boissieri, T. strictum and T. glanduliferum (representing subgenus Chronosemium and subg. Trifolium section Paramesus) were tractable, assembled readily and were not unusual in the general context of Fabeae plastomes. The other Trifolium species (“core Trifolium”) proved refractory to assembly mainly because of numerous short duplications. These species form a single clade, which we call the “refractory clade” (comprising subg, Trifolium sections Lupinaster, Trifolium, Trichocephalum, Vesicastrum and Trifoliastrum). The characteristics of the refractory clade are the presence of numerous short duplications and 7-15% longer genomes than the tractable species. Molecular dating estimates that the origin of the most recent common ancestor (MRCA) of the refractory clade is approximately 13.1 million years ago (MYA). This is considerably younger than the estimated MRCA ages of Trifolium (c. 18.6 MYA) and Trifolium subg. Trifolium (16.1 MYA). Conclusions We conclude that the unusual repetitive plastome type previously characterized in Trifolium subterraneum had a single origin within Trifolium and is characteristic of most (but not all) species of subgenus Trifolium. It appears that an ancestral plastome within Trifolium underwent an evolutionary change resulting in plastomes that either actively promoted, were permissive to, or were unable to control, duplications within the genome. The precise mechanism of this important change in the mode and tempo of plastome evolution deserves further investigation. Electronic supplementary material The online version of this article (doi:10.1186/s12862-014-0228-6) contains supplementary material, which is available to authorized users.

Nigellic acid [(+)( S )-7′-hydroxy-ABA], previously isolated from cell suspension cultures of Nigella damascena fed ± abscisic acid was detected as an endogenous compound in leaves of Vicia faba using gas chromatography/mass spectrometry.