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Whole genome duplication plays a significant role in plant genome evolution by providing raw materials that can be modified by natural or artificial selection. Nucleotide binding site leucine rich repeat receptor (NLRs) like other gene families are clusters of genes created by duplication and their size reflects the number of duplicated genes. NLR genes encode immune receptors that facilitate identification and binding of effector compounds produced by pathogen as a part of effector triggered immunity (ETI). The accurate identification and characterization of NLR genes substantially contributes to the repertoire of resistance and improves production. The ancestors of Fabaceae family have underwent whole genome duplication (WGD) approximately 58.5 million years ago. In this study, we focused on the subsequent effects of WGD on the evolution of NLR genes within the Vicioid clade, which consists of various legume crops such as chickpea, clover, alfalfa, and pea. The Vicioid clade is divided into three major tribes: Cicereae, Fabeae, and Trifolieae. The analysis of 22 species from the Vicioid clade revealed an overall contraction of the NLRome (the complete set of NLR genes) in members of the Cicereae and Fabeae tribes. This contraction aligns with previous observations that WGD events are often followed by diploidization, leading to a reduced number of duplicated genes. Contrary to this contraction trend, tribe Trifolieae have shown large scale expansion of NLRome irrespective to their genome size. Additionally, the primary diversification of relatively conserved NLR gene subclasses, including helper genes (CCR-NLR) and CCG10-NLR, was reported. Comprehensive evolutionary analysis suggests that NLRome expansion have occurred in during recent 1-6 Mya probably due to their higher substitutions per site per year in Trifolieae. We further hypothesized that this higher rate directed accelerated gene duplications after speciation from their common ancestor and later gene conversion and asymmetric recombination played an active role in subgroup diversification.

The European mining bee species Andrena lathyri (Andrenidae) is a narrow specialist of flowers of Lathyrus and Vicia (Fabaceae), from which both females and males gain nectar by primary nectar robbing. Both sexes are equipped with a unique proboscis, which is much longer and more strongly angled than in most other Andrena bees including the most closely related species. The comparison between the shape of the proboscis and the interior of the host flowers combined with field observations revealed that the specialised mouthparts of A. lathyri precisely correspond to the dimensions of the flower interior and the position of the nectary, representing one of the few known examples of a morphological adaptation to primary nectar robbing in bees. For nectar uptake, the bee's head is inserted laterally under the standard petal before it is moved towards the flower base, thereby slitting the calyx longitudinally to a depth necessary to reach the nectary from inside the flower with the specialised proboscis. Nectar-robbing individuals of A. lathyri are able to adapt their behaviour to the different calyx lengths of their host flower species by slitting the calyx over varying distances. Except for the slit in the calyx, primary nectar robbing by A. lathyri does not damage any flower parts allowing for normal fruit development. [ABSTRACT FROM AUTHOR]

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.

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. [ABSTRACT FROM AUTHOR]

The only species of the legume genus Vavilovia, a paleoendemic to the Caucasus commonly known simply as Vavilovia (V. formosa) has an extraordinary significance for the evolution and phylogeny of the tribe Fabeae, with its economically important species, such as lentil (Lens spp.) or pea (Pisum spp). This paper is attempting to deduce the genetic background of the materially perished, but thoroughly described, F1 progeny between Vavilovia and field pea (P. sativum var. arvense) in both crossing combinations, obtained by the N. I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR), in 1988. Although with only one plant in each direction, the resulting phenotypes are the only known successful intergeneric hybridisation in legumes with impressively interesting features, such as the trifoliolate leaves absent in both parents, as well as vastly inspiring and potentially useful for the conservation of Vavilovia and crop improvement of pea and other species of the tribe.

The plastid and mitochondrial genomes of Vavilovia formosa (Stev.) Fed. were assembled on the base of the data of high-throughput sequencing of DNA isolated from a sample from North Osetia, Russia, using Illumina and PacBio platforms. The long PacBio reads were sufficient for reliable assembling organellar genomes while the short Illumina reads obtained from total DNA were unacceptable for this purpose because of substantial contamination by nuclear sequences. The organellar genomes were circular DNA molecules; the genome of mitochondria was represented by two circular chromosomes. A phylogenetic analysis on the basis of plastid genomes available in public databases was performed for some representatives of the tribes Fabeae, Trifolieae and Cicereae. As was expected, the V. formosa branch proved to be sister to the Pisum branch, and the tribe Fabeae was monophyletic. The position of Trifolium L. appeared sensitive to the phylogeny reconstruction method, either clustering with Fabeae or with the genera Medicago L., Trigonella L. and Melilotus Mill., but the internodes between successive divergences were short in all cases, suggesting that the radiation of Trifolium, other Trifolieae and Fabeae was fast, occurring within a small time interval as compared to further evolution of these lineages. The data on the relatedness of the plastid genomes of Trifolium and Fabeae correlate with the similarity of N2-fixing symbionts in these legumes represented by Rhizobium leguminosarum biovars trifolii and viciae, while the symbionts of Medicago, Melilotus and Trigonella belong to the Sinorhizobium meliloti and S. medicae species, which are distant from Rhizobium.

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 = 0.088) indicating limited outcrossing rate. A significantly positive correlation between geographical latitude and leaf area ( $$\rho$$ = 0.527, p < 0.05) was found. Niche modelling has shown temporal variation of predicted occurrence across the projected time periods. Vavilovia formosa has suffered a range reduction following climate warming after last glacial maximum, which classify this species as cold-adapted among the Fabeae species as well as a glacial relict. [ABSTRACT FROM AUTHOR]

Vavilovia (Vavilovia formosa (Stev.) Fed.) belongs to the tribe Fabeae along with peas, vetchlings, vetches and lentils. It prefers high mountain areas in Armenia, Azerbaijan, Georgia, Iran, Iraq, Lebanon, Russia, Syria and Turkey. A true success in the ex situ conservation has recently been achieved, within the display plot Flora and Vegetation of Armenia in the Yerevan Botanic Garden. The hybridization between vavilovia and other Fabeae was done in the N. I. Vavilov Institute of Plant Industry with F1 seeds and F1 plants that did not produce the next generation. The recent molecular research showed that vavilovia belongs to a Lathyrus-Pisum-Vavilovia clade with a clearly distinct status.

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 (<4%) of previously initiated flowers result in production of mature fruits. This many-flowered state is derived from a single- or few-flowered one typical for the most basal representatives of this clade. The single-flowered state strongly correlates with annual life form and arises repeatedly during evolution of tribe Fabeae. The adaptive values of different inflorescence types are discussed. [ABSTRACT FROM AUTHOR]

Highlights: [•] Consumption of proteins contained in legumes has a beneficial effect on health. [•] Knowledge of local plants could provide useful data for development of future crops. [•] A protein characterisation of wild populations of Tribe Fabeae species has been made. [•] Seeds have good nutritional characteristics. [•] Results contribute to revalorize the cultivation of these legumes. [Copyright &y& Elsevier]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Abstract: 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. [Copyright &y& Elsevier]

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. [ABSTRACT FROM AUTHOR]

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 C. 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 4 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.