Chloroplast Phylogenomic Analyses Reveal a Maternal Hybridization Event Leading to the Formation of Cultivated Peanuts

Peanuts (Arachis hypogaea L.) offer numerous healthy benefits, and the production of peanuts has a prominent role in global food security. As a result, it is in the interest of society to improve the productivity and quality of peanuts with transgenic means. However, the lack of a robust phylogeny of cultivated and wild peanut species has limited the utilization of genetic resources in peanut molecular breeding. In this study, a total of 33 complete peanut plastomes were sequenced, analyzed and used for phylogenetic analyses. Our results suggest that sect. Arachis can be subdivided into two lineages. All the cultivated species are contained in Lineage I with AABB and AA are the two predominant genome types present, while species in Lineage II possess diverse genome types, including BB, KK, GG, etc. Phylogenetic studies also indicate that all allotetraploid cultivated peanut species have been derived from a possible maternal hybridization event with one of the diploid Arachis duranensis accessions being a potential AA sub-genome ancestor. In addition, Arachis monticola, a tetraploid wild species, is placed in the same group with all the cultivated peanuts, and it may represent a transitional species, which has been through the recent hybridization event. This research could facilitate a better understanding of the taxonomic status of various Arachis species/accessions and the evolutionary relationship among them, and assists in the correct and efficient use of germplasm resources in breeding efforts to improve peanuts for the benefit of human beings.

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Twelve complete chloroplast genomes of wild peanuts: great genetic resources and a better understanding of Arachis phylogeny

BMC Plant Biology ◽

10.1186/s12870-019-2121-3 ◽

2019 ◽

Vol 19 (1) ◽

Author(s):

Juan Wang ◽

Yuan Li ◽

Chunjuan Li ◽

Caixia Yan ◽

Xiaobo Zhao ◽

...

Keyword(s):

Genetic Resources ◽

Phylogenetic Analyses ◽

Data Set ◽

Genome Species ◽

Chloroplast Genomes ◽

Cultivated Peanut ◽

Ssr Loci ◽

Aa Genome ◽

Cp Genome ◽

Wild Peanut

Abstract Background The cultivated peanut (Arachis hypogaea) is one of the most important oilseed crops worldwide, however, its improvement is restricted by its narrow genetic base. The highly variable wild peanut species, especially within Sect. Arachis, may serve as a rich genetic source of favorable alleles to peanut improvement; Sect. Arachis is the biggest taxonomic section within genus Arachis and its members also include the cultivated peanut. In order to make good use of these wild resources, the genetic bases and the relationships of the Arachis species need first to be better understood. Results Here, in this study, we have sequenced and/or assembled twelve Arachis complete chloroplast (cp) genomes (eleven from Sect. Arachis). These cp genome sequences enriched the published Arachis cp genome data. From the twelve acquired cp genomes, substantial genetic variation (1368 SNDs, 311 indels) has been identified, which, together with 69 SSR loci that have been identified from the same data set, will provide powerful tools for future explorations. Phylogenetic analyses in our study have grouped the Sect. Arachis species into two major lineages (I & II), this result together with reports from many earlier studies show that lineage II is dominated by AA genome species that are mostly perennial, while lineage I includes species that have more diverse genome types and are mostly annual/biennial. Moreover, the cultivated peanuts and A. monticola that are the only tetraploid (AABB) species within Arachis are nested within the AA genome species-dominated lineage, this result together with the maternal inheritance of chloroplast indicate a maternal origin of the two tetraploid species from an AA genome species. Conclusion In summary, we have acquired sequences of twelve complete Arachis cp genomes, which have not only helped us better understand how the cultivated peanut and its close wild relatives are related, but also provided us with rich genetic resources that may hold great potentials for future peanut breeding.

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A new insular species of the Cyrtodactylus pulchellus group (Reptilia, Gekkonidae) from Tarutao Island, southern Thailand revealed by morphological and genetic evidence

ZooKeys ◽

10.3897/zookeys.1070.73659 ◽

2021 ◽

Vol 1070 ◽

pp. 101-134

Author(s):

Korkhwan Termprayoon ◽

Attapol Rujirawan ◽

Natee Ampai ◽

Perry L. Wood Jr ◽

Anchalee Aowphol

Keyword(s):

Phylogenetic Analyses ◽

Taxonomic Status ◽

Morphological Characters ◽

Molecular Data ◽

Species Group ◽

Phylogenetic Studies ◽

Southern Thailand ◽

Pairwise Divergence ◽

Morphological And Molecular Data ◽

Dark Body

The bent-toed geckos of the Cyrtodactylus pulchellus group are widely distributed along the Thai-Malay Peninsula. Although taxonomic and phylogenetic studies of this species group have been continuously conducted, only some populations from Thailand have been included, resulting in hidden diversity within this group. In this study, we used morphological and molecular data to clarify the taxonomic status and describe a new population from Tarutao Island, Satun Province, southern Thailand. Cyrtodactylus stellatussp. nov. can be distinguished from its congeners by the combination of the following morphological characters: body size; tuberculation; number of dark body bands, ventral scales, and femoroprecloacal pores in males; presence of precloacal pores in females; and scattered pattern on dorsum. Phylogenetic analyses of the mitochondrial ND2 gene recovered the new species as the sister species to C. astrum, with an uncorrected pairwise divergence of 9.78–12.37%. Cyrtodactylus stellatussp. nov. is currently only known from Tarutao Island, Thailand. The discovery of this species suggests that the diversity within the C. pulchellus group remains underestimated and future exploration of unsurveyed areas are needed to further the understanding of this group and its geographic range.

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Diversification of the North American Doellingeria-Eucephalus Clade (Astereae: Asteraceae) Inferred from Molecular and Morphological Evidence

Systematic Botany ◽

10.1600/036364419x15710776741477 ◽

2019 ◽

Vol 44 (4) ◽

pp. 930-942

Author(s):

Geraldine A. Allen ◽

Luc Brouillet ◽

John C. Semple ◽

Heidi J. Guest ◽

Robert Underhill

Keyword(s):

North American ◽

Sequence Data ◽

Phylogenetic Analyses ◽

Sister Group ◽

Morphological Evidence ◽

South American ◽

New Combinations ◽

The North ◽

Hybridization Event ◽

Ancient Hybridization

Abstract—Doellingeria and Eucephalus form the earliest-diverging clade of the North American Astereae lineage. Phylogenetic analyses of both nuclear and plastid sequence data show that the Doellingeria-Eucephalus clade consists of two main subclades that differ from current circumscriptions of the two genera. Doellingeria is the sister group to E. elegans, and the Doellingeria + E. elegans subclade in turn is sister to the subclade containing all remaining species of Eucephalus. In the plastid phylogeny, the two subclades are deeply divergent, a pattern that is consistent with an ancient hybridization event involving ancestral species of the Doellingeria-Eucephalus clade and an ancestral taxon of a related North American or South American group. Divergence of the two Doellingeria-Eucephalus subclades may have occurred in association with northward migration from South American ancestors. We combine these two genera under the older of the two names, Doellingeria, and propose 12 new combinations (10 species and two varieties) for all species of Eucephalus.

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Towards a Natural Classification of Hyphodontia Sensu Lato and the Trait Evolution of Basidiocarps within Hymenochaetales (Basidiomycota)

Journal of Fungi ◽

10.3390/jof7060478 ◽

2021 ◽

Vol 7 (6) ◽

pp. 478

Author(s):

Xue-Wei Wang ◽

Tom W. May ◽

Shi-Liang Liu ◽

Li-Wei Zhou

Keyword(s):

Phylogenetic Analyses ◽

Taxonomic Status ◽

Ancestral State ◽

Trait Evolution ◽

Natural Classification ◽

Multiple Loci ◽

The Family ◽

Phylogenetic Perspective ◽

Taxonomic Framework ◽

First Time

Hyphodontia sensu lato, belonging to Hymenochaetales, accommodates corticioid wood-inhabiting basidiomycetous fungi with resupinate basidiocarps and diverse hymenophoral characters. Species diversity of Hyphodontia sensu lato has been extensively explored worldwide, but in previous studies the six accepted genera in Hyphodontia sensu lato, viz. Fasciodontia, Hastodontia, Hyphodontia, Kneiffiella, Lyomyces and Xylodon were not all strongly supported from a phylogenetic perspective. Moreover, the relationships among these six genera in Hyphodontia sensu lato and other lineages within Hymenochaetales are not clear. In this study, we performed comprehensive phylogenetic analyses on the basis of multiple loci. For the first time, the independence of each of the six genera receives strong phylogenetic support. The six genera are separated in four clades within Hymenochaetales: Fasciodontia, Lyomyces and Xylodon are accepted as members of a previously known family Schizoporaceae, Kneiffiella and Hyphodontia are, respectively, placed in two monotypic families, viz. a previous name Chaetoporellaceae and a newly introduced name Hyphodontiaceae, and Hastodontia is considered to be a genus with an uncertain taxonomic position at the family rank within Hymenochaetales. The three families emerged between 61.51 and 195.87 million years ago. Compared to other families in the Hymenochaetales, these ages are more or less similar to those of Coltriciaceae, Hymenochaetaceae and Oxyporaceae, but much older than those of the two families Neoantrodiellaceae and Nigrofomitaceae. In regard to species, two, one, three and 10 species are newly described from Hyphodontia, Kneiffiella, Lyomyces and Xylodon, respectively. The taxonomic status of additional 30 species names from these four genera is briefly discussed; an epitype is designated for X. australis. The resupinate habit and poroid hymenophoral configuration were evaluated as the ancestral state of basidiocarps within Hymenochaetales. The resupinate habit mainly remains, while the hymenophoral configuration mainly evolves to the grandinioid-odontioid state and also back to the poroid state at the family level. Generally, a taxonomic framework for Hymenochaetales with an emphasis on members belonging to Hyphodontia sensu lato is constructed, and trait evolution of basidiocarps within Hymenochaetales is revealed accordingly.

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ValSten: a new wild species derived allotetraploid for increasing genetic diversity of the peanut crop (Arachis hypogaea L.)

Genetic Resources and Crop Evolution ◽

10.1007/s10722-020-01076-2 ◽

2021 ◽

Author(s):

Dongying Gao ◽

Ana C. G. Araujo ◽

Eliza F. M. B. Nascimento ◽

M. Carolina Chavarro ◽

Han Xia ◽

...

Keyword(s):

High Resistance ◽

Wild Species ◽

Chromosome Doubling ◽

Crop Improvement ◽

Snp Array ◽

Great Majority ◽

Morphological Variations ◽

Peanut Crop ◽

Cultivated Peanut ◽

Wild Peanut

AbstractIntrogression of desirable traits from wild relatives plays an important role in crop improvement, as wild species have important characters such as high resistance to pests and pathogens. However, use of wild peanut relatives is challenging because almost all wild species are diploid and sexually incompatible with cultivated peanut, which is tetraploid (AABB genome type; 2n = 4x = 40). To overcome the ploidy barrier, we used 2 wild species to make a tetraploid with the same allotetraploid genome composition as cultivated peanut. Crosses were made between 2 diploid wild species, Arachis valida Krapov. and W.C. Greg. (BB genome; 2n = 2x = 20) and Arachis stenosperma Krapov. and W.C. Greg. (AA genome; 2n = 2x = 20). Cuttings from the diploid F1 AB hybrid were treated with colchicine to induce chromosome doubling thus generating an induced allotetraploid. Chromosome counts confirmed polyploidy (AABB genome; 2n = 4x = 40). We named the new allotetraploid ValSten. Plants had well-developed fertile pollen, produced abundant seed and were sexually compatible with cultivated peanut. ValSten exhibits the same high resistance to early and late leaf spot and rust as its diploid parents. Notably, we observed morphological variations, including flower width and branch angles in the earliest generation (S0) of allotetraploids. A SNP array was used to genotype 47 S0 allotetraploids. The great majority of markers showed the additive allelic state from both parents (AABB). However, some loci were AAAA or BBBB, indicating homeologous recombination. ValSten provides a new, vigorous, highly fertile, disease resistant germplasm for peanut research and improvement.

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Diversity unearthed by the estimated molecular phylogeny and ecologically quantitative characteristics of uncultured Ehrlichia bacteria in Haemaphysalis ticks, Japan

Scientific Reports ◽

10.1038/s41598-020-80690-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Hongru Su ◽

Eri Onoda ◽

Hitoshi Tai ◽

Hiromi Fujita ◽

Shigetoshi Sakabe ◽

...

Keyword(s):

Phylogenetic Analysis ◽

16S Rrna ◽

Core Genome ◽

Phylogenetic Analyses ◽

Taxonomic Status ◽

Housekeeping Genes ◽

Pcr Screening ◽

Taxonomic Profiling ◽

Quantitative Characteristics

AbstractEhrlichia species are obligatory intracellular bacteria transmitted by arthropods, and some of these species cause febrile diseases in humans and livestock. Genome sequencing has only been performed with cultured Ehrlichia species, and the taxonomic status of such ehrlichiae has been estimated by core genome-based phylogenetic analysis. However, many uncultured ehrlichiae exist in nature throughout the world, including Japan. This study aimed to conduct a molecular-based taxonomic and ecological characterization of uncultured Ehrlichia species or genotypes from ticks in Japan. We first surveyed 616 Haemaphysalis ticks by p28-PCR screening and analyzed five additional housekeeping genes (16S rRNA, groEL, gltA, ftsZ, and rpoB) from 11 p28-PCR-positive ticks. Phylogenetic analyses of the respective genes showed similar trees but with some differences. Furthermore, we found that V1 in the V1–V9 regions of Ehrlichia 16S rRNA exhibited the greatest variability. From an ecological viewpoint, the amounts of ehrlichiae in a single tick were found to equal approx. 6.3E+3 to 2.0E+6. Subsequently, core-partial-RGGFR-based phylogenetic analysis based on the concatenated sequences of the five housekeeping loci revealed six Ehrlichia genotypes, which included potentially new Ehrlichia species. Thus, our approach contributes to the taxonomic profiling and ecological quantitative analysis of uncultured or unidentified Ehrlichia species or genotypes worldwide.

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Outbreak of Leaf Spot and Fruit Rot in Florida Strawberry Caused by Neopestalotiopsis spp.

Plant Disease ◽

10.1094/pdis-06-20-1290-re ◽

2021 ◽

pp. PDIS-06-20-1290

Author(s):

Juliana S. Baggio ◽

Bruna B. Forcelini ◽

Nan-Yi Wang ◽

Rafaela G. Ruschel ◽

James C. Mertely ◽

...

Keyword(s):

Internal Transcribed Spacer ◽

Phylogenetic Analyses ◽

Morphological Characteristics ◽

Taxonomic Status ◽

Spore Production ◽

Potato Dextrose Agar ◽

Fruit Rot ◽

Low Genetic Diversity ◽

Pathogenicity Tests ◽

A New Species

Pestalotiopsis-like species have been reported affecting strawberry worldwide. Recently, severe and unprecedented outbreaks have been reported in Florida commercial fields where leaf, fruit, petiole, crown, and root symptoms were observed, and yield was severely affected. The taxonomic status of the fungus is confusing because it has gone through multiple reclassifications over the years. Morphological characteristics, phylogenetic analyses, and pathogenicity tests were evaluated for strawberry isolates recovered from diseased plants in Florida. Phylogenetic analyses derived from the combined internal transcribed spacer, β-tub, and tef1 regions demonstrated that although there was low genetic diversity among the strawberry isolates, there was a clear separation of the isolates in two groups. The first group included isolates recovered over a period of several years, which was identified as Neopestalotiopsis rosae. Most isolates recovered during the recent outbreaks were genetically different and may belong to a new species. On potato dextrose agar, both groups produced white, circular, and cottony colonies. From the bottom, colonies were white to pale yellow for Neopestalotiopsis sp. and pale luteous to orange for N. rosae. Spores for both groups were five-celled with three median versicolored cells. Mycelial growth and spore production were higher for the new Neopestalotiopsis sp. isolates. Isolates from both groups were pathogenic to strawberry roots and crowns. However, the new Neopestalotiopsis sp. proved more aggressive in fruit and leaf inoculation tests, confirming observations from the recent outbreaks in commercial strawberry fields in Florida.

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The first mitochondrial genome of the genus Exhippolysmata (Decapoda: Caridea: Lysmatidae), with gene rearrangements and phylogenetic associations in Caridea

Scientific Reports ◽

10.1038/s41598-021-93946-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ying-ying Ye ◽

Jing Miao ◽

Ya-hong Guo ◽

Li Gong ◽

Li-hua Jiang ◽

...

Keyword(s):

Mitochondrial Genome ◽

Gene Order ◽

Phylogenetic Analyses ◽

Complete Mitochondrial Genome ◽

Bootstrap Support ◽

Trna Genes ◽

Gene Rearrangements ◽

Phylogenetic Studies ◽

Gc Skew ◽

Strong Bootstrap Support

AbstractThe complete mitochondrial genome (mitogenome) of animals can provide useful information for evolutionary and phylogenetic analyses. The mitogenome of the genus Exhippolysmata (i.e., Exhippolysmata ensirostris) was sequenced and annotated for the first time, its phylogenetic relationship with selected members from the infraorder Caridea was investigated. The 16,350 bp mitogenome contains the entire set of 37 common genes. The mitogenome composition was highly A + T biased at 64.43% with positive AT skew (0.009) and negative GC skew (− 0.199). All tRNA genes in the E. ensirostris mitogenome had a typical cloverleaf secondary structure, except for trnS1 (AGN), which appeared to lack the dihydrouridine arm. The gene order in the E. ensirostris mitogenome was rearranged compared with those of ancestral decapod taxa, the gene order of trnL2-cox2 changed to cox2-trnL2. The tandem duplication-random loss model is the most likely mechanism for the observed gene rearrangement of E. ensirostris. The ML and BI phylogenetic analyses place all Caridea species into one group with strong bootstrap support. The family Lysmatidae is most closely related to Alpheidae and Palaemonidae. These results will help to better understand the gene rearrangements and evolutionary position of E. ensirostris and lay a foundation for further phylogenetic studies of Caridea.

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A description of the second species of the genus Bleptus Eaton, 1885 (Ephemeroptera: Heptageniidae) from Japan, and phylogenetic relationships of two Bleptus mayflies inferred from mitochondrial and nuclear gene sequences

Zootaxa ◽

10.11646/zootaxa.4974.2.5 ◽

2021 ◽

Vol 4974 (2) ◽

pp. 333-360

Author(s):

KOJI TOJO ◽

KEN MIYAIRI ◽

YUTO KATO ◽

AYANA SAKANO ◽

TOMOYA SUZUKI

Keyword(s):

Phylogenetic Analyses ◽

Ribosomal Subunit ◽

Nuclear Gene ◽

Taxonomic Status ◽

16S Rrna Genes ◽

Rrna Genes ◽

Gene Sequences ◽

Molecular Phylogenetic ◽

Black Band ◽

Relationship Of

A new mayfly species, Bleptus michinokuensis sp. nov. (Ephemeroptera: Heptageniidae) is described on the basis of specimens of male and female adults and mature nymphs collected at a seepage zone of a small freshwater branch of the ‘Tachiya-zawa-gawa’ River located amongst the northern foothills of Mt. Gassan (Shonai-machi Town, Yamagata Prefecture, Japan). This new Bleptus species is characterized by its clear fore and hind wings. That is, they neither exhibit the distinct black band on the fore wings, nor the characteristic darkened margins along the edges of both the fore and hind wings. Rather it has a blackish colored terminal half of its fore legs (i.e., tibial, tarsal and pretarsal segments). These features differ clearly when comparing them to the other known species, Bleptus fasciatus Eaton. The information and data describing the habitat and distribution range of this new species are also noted. We also examined and discussed the genetic relationship of two Bleptus mayflies to settle the taxonomic status, inferred from the partially sequenced cytochrome c oxidase subunit I (COI) and large mitochondrial ribosomal subunit (16S rRNA) genes, and also the nuclear internal transcribed spacer 2 (ITS2) gene sequences. Consequently, phenetic and molecular phylogenetic analyses agreed well in terms of clustering.

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Mimaporia, a new genus of Epicopeiidae (Lepidoptera), with description of a new species from Vietnam

Zootaxa ◽

10.11646/zootaxa.4254.5.3 ◽

2017 ◽

Vol 4254 (5) ◽

pp. 537 ◽

Cited By ~ 5

Author(s):

CHIA-HSUAN WEI ◽

SHEN-HORN YEN

Keyword(s):

New Species ◽

New Genus ◽

Sequence Data ◽

Phylogenetic Analyses ◽

Taxonomic Status ◽

Sister Group ◽

Morphological Evidence ◽

New Taxon ◽

The Family ◽

A New Species

The Epicopeiidae is a small geometroid family distributed in the East Palaearctic and Oriental regions. It exhibits high morphological diversity in body size and wing shape, while their wing patterns involve in various complex mimicry rings. In the present study, we attempted to describe a new genus, and a new species from Vietnam, with comments on two assumed congeneric novel species from China and India. To address its phylogenetic affinity, we reconstructed the phylogeny of the family by using sequence data of COI, EF-1α, and 28S gene regions obtained from seven genera of Epicopeiidae with Pseudobiston pinratanai as the outgroup. We also compared the morphology of the new taxon to other epicopeiid genera to affirm its taxonomic status. The results suggest that the undescribed taxon deserve a new genus, namely Mimaporia gen. n. The species from Vietnam, Mimaporia hmong sp. n., is described as new to science. Under different tree building strategies, the new genus is the sister group of either Chatamla Moore, 1881 or Parabraxas Leech, 1897. The morphological evidence, which was not included in phylogenetic analyses, however, suggests its potential affinity with Burmeia Minet, 2003. This study also provides the first, although preliminary, molecular phylogeny of the family on which the revised systematics and interpretation of character evolution can be based.

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