Biosystematic study of hexaploids Elymus tschimganicus and E. glaucissimus. II. Interspecific hybridization and genomic relationship

Genome ◽  
1993 ◽  
Vol 36 (6) ◽  
pp. 1157-1168 ◽  
Author(s):  
Bao-Rong Lu ◽  
Kevin B. Jensen ◽  
Björn Salomon
Keyword(s):  
Interspecific Hybridization ◽  
General Pattern ◽  
The Other ◽  
South American ◽  
Genomic Relationship ◽  
Target Species ◽  
Species Relationship ◽  
Genomic Relationships ◽  
Pairing Behavior ◽  
Elymus Species

To investigate genomic relationships of Elymus tschimganicus (Drobov) Tzvelev (2n = 6x = 42, S1S2Y genomes) and E. glaucissimus (M. Pop.) Tzvelev (2n = 6x = 42, S1S2Y genomes), interspecific hybridizations of the two target species were carried out with 27 other Elymus species containing the SH, SY, SYH, SYP, SYW, and SH1H2 genomes, respectively, collected from different geographic regions. Chromosome pairing behavior was analyzed at metaphase I in 27 hybrids representing 23 hybrid combinations, and overall genomic relationships of the two target species with the other Elymus taxa were estimated. The study concluded that (i) interspecific hybridization was principally easy to perform between the Elymus species, but no general pattern of crossability was obtained, and all hybrids were completely sterile, (ii) the two species have a similar meiotic pattern in their hybrids with the other Elymus species, and (iii) species containing the SY, SYP, and SYH genomes have a generally higher level of genomic homology to the target species than those possessing the SH genomes, and the South American hexaploid with the SH1H2 genomes has the lowest level of genomic homology to the two target taxa.Key words: Elymus, interspecific hybridization, meiosis, genome, species relationship.

Description, distribution and ecology of endemic Tasmanian quillwort, Isoetes jarmaniae, sp. nov. (Isoetaceae; Lycopodiopsida)

Phytotaxa ◽  
2021 ◽  
Vol 522 (1) ◽  
pp. 27-37
Author(s):  
DANIEL F. BRUNTON ◽  
MICHAEL GARRETT ◽  
PAUL C. SOKOLOFF ◽  
GINTARAS KANTVILAS
Keyword(s):  
Diploid Species ◽  
Geographic Range ◽  
The Other ◽  
South American ◽  
The South ◽  
Triangular Shape ◽  
South West ◽  
Distribution And Ecology ◽  
River Valleys

Isoetes jarmaniae sp. nov. is described as a new lycophyte endemic to Tasmania, Australia, where it is confined to peat-bound karstic wetlands in several river valleys in the south-west wilderness. While seemingly morphologically closest to I. drummondii, this quillwort has features that are globally uncommon in Isoetes and unknown in other Australasian taxa. Most notable are its markedly flattened, strongly recurved leaves and disproportionately large sporangium ligules that are more suggestive of South American than Australian taxa. As well, the exceptionally thin and wide (alate) megaspore equatorial ridge is swollen at suture intersections, presenting a slightly triangular shape suggestive of the Indian taxon I. udupiensis. The microspores of I. jarmaniae exhibit exceptionally, perhaps uniquely, fine-papillate ornamentation. An original key placing I. jarmaniae in context with the other Tasmanian Isoetes species is provided. This diminutive, apparently diploid species is evidently maintaining a self-sustaining population within a regionally unique habitat and small geographic range.

scholarly journals Clinical and Genetic Spectrum of Stargardt Disease in Argentinean Patients

2021 ◽  
Vol 12 ◽  
Author(s):  
Marcela D. Mena ◽  
Angélica A. Moresco ◽  
Sofía H. Vidal ◽  
Diana Aguilar-Cortes ◽  
María G. Obregon ◽  
...  
Keyword(s):  
Retrospective Study ◽  
Next Generation Sequencing ◽  
Final Analysis ◽  
The Other ◽  
South American ◽  
Stargardt Disease ◽  
Targeted Next Generation Sequencing ◽  
Mutational Spectrum ◽  
Genetic Features ◽  
Generation Sequencing

PurposeTo describe the clinical and molecular spectrum of Stargardt disease (STGD) in a cohort of Argentinean patients.MethodsThis retrospective study included 132 subjects comprising 95 probands clinically diagnosed with STGD and relatives from 16 of them. Targeted next-generation sequencing of the coding and splicing regions of ABCA4 and other phenocopying genes (ELOVL4, PROM1, and CNGB3) was performed in 97 STGD patients.ResultsWe found two or more disease-causing variants in the ABCA4 gene in 69/95 (73%) probands, a single ABCA4 variant in 9/95 (9.5%) probands, and no ABCA4 variants in 17/95 (18%) probands. The final analysis identified 173 variants in ABCA4. Seventy-nine ABCA4 variants were unique, of which nine were novel. No significant findings were seen in the other evaluated genes.ConclusionThis study describes the phenotypic and genetic features of STGD1 in an Argentinean cohort. The mutations p.(Gly1961Glu) and p.(Arg1129Leu) were the most frequent, representing almost 20% of the mutated alleles. We also expanded the ABCA4 mutational spectrum with nine novel disease-causing variants, of which eight might be associated with South American natives.

Constitutional History

2016 ◽  
Author(s):  
Olof Petersson
Keyword(s):  
Welfare State ◽  
General Pattern ◽  
Public Life ◽  
Constitutional Reform ◽  
The Other ◽  
Constitutional History ◽  
History Writing ◽  
Parliamentary Government ◽  
Other Hand ◽  
Trade Offs

In one sense, Sweden follows the general pattern of constitution-making. The major shifts in the constitutional history have occurred in the aftermath of great crises. Constitutions have been important as descriptions and justifications of the prevailing forces of power. On the other hand, the constitutions of Sweden have been relatively insignificant as norms regulating political and public life. Constitutions have been important as history writing but relatively unimportant as normative principles shaping society, and, indeed, profound changes such as the introduction of parliamentary government have taken place without constitutional reform. The Swedish welfare state was built upon negotiations and practical trade-offs rather than constitutional arguments.

The effect of nutrition on fibre characteristics and production in the alpaca

1995 ◽  
Vol 1995 ◽  
pp. 101-101
Author(s):  
A.J.F. Russel ◽  
H. Redden ◽  
J.W. Kay
Keyword(s):  
Animal Species ◽  
Fibre Length ◽  
Fibre Production ◽  
The Other ◽  
South American ◽  
Cashmere Goat ◽  
Lack Of Information ◽  
The Relationship ◽  
Positive Effect ◽  
Fibre Characteristics

In single-coated animal species selected for fibre production, such as sheep and Angora goats, nutrition is known to have a positive effect on fibre length and diameter, and hence on the weight of fibre produced, while in double-coated species, such as the cashmere goat, the fibre characteristics of the undercoat appear relatively insensitive to nutritional influence. Recent studies on the relationship between nutrition and fibre production in the llama, a double-coated species, indicate that it conforms to the above generalisation in that the growth rate and diameter of its fibre are not amenable to nutritional manipulation (Russel and Redden, 1994). There is a lack of information on the effects of nutrition on fibre characteristics and production in the other domesticated species of South American camelid, the single-coated alpaca. The experiment reported here was designed to provide such information.

Grupo Andino and its Documents

1988 ◽  
Vol 16 (2) ◽  
pp. 83-100
Author(s):  
Igor I. Kavass
Keyword(s):  
Foreign Trade ◽  
Economic Integration ◽  
Investment Policy ◽  
Common Market ◽  
The Other ◽  
Mountain Range ◽  
South American ◽  
Andean Pact ◽  
Trade And Investment

The Grupo Andino (also known as the Andean Common Market (or ANCOM), Acuerdo de Cartagena, and the Andean Pact) is an organization for the economic integration of the five South American countries located in the central and northern parts of the massive Andean mountain range. The present members of the organization are Bolivia, Colombia, Ecuador, Peru and Venezuela. Originally, when the Grupo Andino was established by means of a treaty known as the Cartagena Agreement (Acuerdo de Cartagena) in 1969, Chile was one of the founding members, whereas Venezuela abstained from joining the organization until 1973. As Chile began to develop a more flexible foreign trade and investment policy in the middle 1970's than was acceptable to the other Grupo Andino countries, it gradually withdrew from the organization's activities, and finally ceased to be a member in late 1976.

The Separation and Characterization of Graft Copolymers from Natural Rubber

1958 ◽  
Vol 31 (4) ◽  
pp. 819-828 ◽  
Author(s):  
F. M. Merret
Keyword(s):  
Natural Rubber ◽  
Intrinsic Viscosity ◽  
Benzene Solution ◽  
Graft Copolymers ◽  
General Pattern ◽  
The Other ◽  
Vinyl Monomers ◽  
Major Increase ◽  
Made In

Abstract The solubility of graft copolymers prepared from rubber and vinyl monomers follows a general pattern whereby one of the constituents can be insolubilized while the other remains soluble, the compound forming a stable sol which is largely unaffected by heat or ionic materials at suitable ratios of solvent to precipitant. The onset and flocculation of the sol are such that the graft copolymer can be completely separated from either free constituent homopolymer. This insolubilization of the rubber trunk chain by addition of methanol to a benzene solution of the coploymer has been followed by the changes in the intrinsic viscosity and turbidity, which show that the collapse of the rubber chain continues to a point beyond where the molecularly equivalent free rubber would be precipitated. This period also marks the major increase in turbidity. Osmotic data show that μ-values for the grafted copolymers of rubber are the same as for rubber itself, thus supporting similar assumptions made in the application of the theory of the equilibirium swelling of crosslinked rubber.

Identification and diagnosis of Leishmania mexicana complex isolates by polymerase chain reaction

Parasitology ◽  
1994 ◽  
Vol 109 (4) ◽  
pp. 423-433 ◽  
Author(s):  
S. Eresh ◽  
S. M. McCallum ◽  
D. C. Barker
Keyword(s):  
Polymerase Chain Reaction ◽  
Dna Sequences ◽  
The Other ◽  
South American ◽  
Kinetoplast Dna ◽  
Leishmania Mexicana ◽  
Chain Reaction ◽  
Potential Host ◽  
Oligonucleotide Primers ◽  
Polymerase Chain

SUMMARYFollowing cloning of Leishmania (L.) amazonensis kinetoplast DNA two recombinant clones were identified: one specific for L. (L.) amazonensis and the other specific for L. (L.) amazonensis and closely related isolates. DNA sequences from these clones were compared with those of other kinetoplastids and oligonucleotide primers were designed to be used in the polymerase chain reaction. A pair of these primers has been shown not only to be highly specific for L. mexicana complex isolates but can also be used to distinguish between L. (L.) mexicana and L. (L.) amazonensis isolates. These primers have been tested with water-lysed cultures, crude DNA extracts from human patients, potential host reservoirs, sandfly vectors and with cell pellets after isoenzyme characterization. The results of these tests indicate that the primers can be used specifically in the presence of excess host DNA originating from the majority of South American countries.

Redescription of the rare South American worm lizard Amphisbaena rozei (Squamata: Amphisbaenidae)

2018 ◽  
Vol 39 (1) ◽  
pp. 21-30 ◽  
Author(s):  
Henrique C. Costa ◽  
Josefa Celsa Señaris ◽  
Fernando J.M. Rojas-Runjaic ◽  
Hussam Zaher ◽  
Paulo C.A. Garcia
Keyword(s):  
River Basin ◽  
Dorsal Surface ◽  
Original Description ◽  
Relevant Information ◽  
The Other ◽  
South American ◽  
Type Specimens

Amphisbaena rozeiis endemic to the Caura River basin in Venezuela, and known only from the holotype and one paratype. Its original description is very brief, lacking relevant information used by taxonomists today. Additionally,A. rozeiappears to be similar toA. spurrelli, a species from northwestern Colombia and southern Panama. We present a redescription ofA. rozeibased on the examination of the type specimens and compare this taxon to the other known South American amphisbaenids, especiallyA. spurrelli. We concludeA. rozeiis a valid name, and the species is diagnosed mainly by the presence of four precloacal pores, a lateral sulcus, 205–209 body annuli, 20 caudal annuli, 15–16 dorsal and 14 ventral segments on a midbody annulus, and dorsal surface of tail covered by strong tubercles.

Revision of the Australian ants of the genus Monomorium (Hymenoptera : Formicidae)

2001 ◽  
Vol 15 (3) ◽  
pp. 353 ◽  
Author(s):  
Brian E. Heterick
Keyword(s):  
Common Ancestor ◽  
Arid Zone ◽  
Cladistic Analysis ◽  
The Other ◽  
Sister Taxon ◽  
South American ◽  
Species Status ◽  
Incertae Sedis ◽  
Species Inquirenda ◽  
Species Groups

The Australian ants of the genus Monomorium are revised. Fifty-nine species are recognised. Of these, 41 are described as new: Monomorium aithoderum, M. albipes, M. anderseni, M. anthracinum, M. arenarium, M. bifidum, M. bihamatum, M. brachythrix, M. burchera, M. capito, M. carinatum, M. castaneum, M. crinitum, M. decuria, M. disetigerum, M. draculai, M. durokoppinense, M. elegantulum, M. eremophilum, M. euryodon, M. flavonigrum, M. lacunosum, M. legulus, M. longinode, M. macarthuri, M. majeri, M. megalops, M. micula, M. nanum, M. nightcapense, M. nigriceps, M. parantarcticum, M. petiolatum, M. pubescens, M. ravenshoense, M. rufonigrum, M. shattucki, M. silaceum, M. stictonotum, M. striatifrons, and M. xantheklemma. Thirteen species pass into synonymy: M. armstrongi with M. whitei, M. broomense and M. ilia with M. laeve, M. donisthorpeiand M. fraterculus with M. fieldi, M. flavipes and M. insularis with M. leae, M. foreli with M. sordidum, M. howense with M. tambourinense, M. macareaveyi with M. bicorne, M. sanguinolentum with M. rubriceps, M. subapterum with M. rothsteini, and M. turneri withM. gilberti. Sixteen infraspecific forms are also synonymised: M. kilianii obscurelluminto M. kilianii, M. laeve nigriusand M. laeve fraterculus into M. fieldi, M. ilia lamingtonensisinto M. laeve, M. rothsteini humilior, M. rothsteini leda, M. rothsteini doddi and M. subapterum bogischi into M. rothsteini, M. rothsteini squamigena, M. rothsteini tostum and M. sordidum nigriventris into M. sordidum, M. fraterculus barretti and M. sydneyense nigella into M. sydneyense, M. gilberti mediorubra into M. gilberti, and M. rubriceps cinctumand M. rubriceps rubrum into M. rubriceps. Seventeen species and one subspecies are unchanged. Monomorium kiliani reverts to M. kilianii, M. kilianii tambourinenseis raised to species status, M. occidaneus is here treated as a species inquirenda, and M. flavigaster is removed from the genus Monomorium. Since the generic status of the latter taxon is uncertain, M. flavigaster is here regarded as incertae sedis. The supposedly extralimitalMonomorium talpa is synonymised under Monomorium australicum. At a higher taxonomic level the South American genus Antichthonidris is synonymised under Monomorium. Seven species-groups are proposed for the Australian fauna, (the bicorne-, falcatum-, insolescens-, kilianii-, longinode-, monomorium-, and rubriceps-groups). A cladistic analysis was undertaken of species for which all castes were examined (identifiable males and/or queens were lacking for all members of the falcatum-, insolescens- and longinode-groups). In all, fifteen species of Australian Monomorium were examined (M. bicorne, M. whitei, M. striatifrons and M. rufonigrum from the bicorne-group, M. crinitumand M. kilianii from the kilianii-group, M. fieldi, M. laeve, M. rothsteini, M. sordidum and M. sydneyense from the monomorium-group, and M. centrale, M. leae, M. euryodon and M. rubriceps from the rubriceps-group), together with Monomorium antarcticum(from New Zealand) and the Neotropical Antichthonidris denticulatus. The taxon used for the outgroup was the Neotropical ant Megalomyrmex modestus. Using the PAUP program, 37 characters for worker, queen and male castes were analysed. The clade incorporating the tiny generalists (M. fieldi, M. laeve, M. sordidum, and M. sydneyense), together with M. rothsteini, was found to be the clade most strongly supported as a monophyletic grouping. In this analysis M. euryodon was the sister taxon to the above clade. These ants were shown on this analysis to share a common ancestor with the other members of the rubriceps-group, with M. antarcticum and A. denticulatus, and with thekilianii-group. The relationships between these latter four sets of species were left unresolved, except that M. crinitum was shown to be the sister taxon to M. kilianii. The large, arid zone species in thebicorne-group were also shown as ancestral to the other Australian Monomorium. A key is provided to enable researchers to identify the workers of all Australian Monomorium, as well as extralimital species established in Australia.

scholarly journals Genomic predictions for enteric methane production are improved by metabolome and microbiome data in sheep (Ovis aries)

2020 ◽  
Vol 98 (10) ◽  
Author(s):  
Elizabeth M Ross ◽  
Ben J Hayes ◽  
David Tucker ◽  
Jude Bond ◽  
Stuart E Denman ◽  
...  
Keyword(s):  
Methane Production ◽  
Prediction Accuracy ◽  
Live Weight ◽  
Ovis Aries ◽  
Prediction Algorithm ◽  
Genomic Relationship ◽  
Time Points ◽  
Genomic Relationships ◽  
Genomic Predictions ◽  
Time Point

Abstract Methane production from rumen methanogenesis contributes approximately 71% of greenhouse gas emissions from the agricultural sector. This study has performed genomic predictions for methane production from 99 sheep across 3 yr using a residual methane phenotype that is log methane yield corrected for live weight, rumen volume, and feed intake. Using genomic relationships, the prediction accuracies (as determined by the correlation between predicted and observed residual methane production) ranged from 0.058 to 0.220 depending on the time point being predicted. The best linear unbiased prediction algorithm was then applied to relationships between animals that were built on the rumen metabolome and microbiome. Prediction accuracies for the metabolome-based relationships for the two available time points were 0.254 and 0.132; the prediction accuracy for the first microbiome time point was 0.142. The second microbiome time point could not successfully predict residual methane production. When the metabolomic relationships were added to the genomic relationships, the accuracy of predictions increased to 0.274 (from 0.201 when only the genomic relationship was used) and 0.158 (from 0.081 when only the genomic relationship was used) for the two time points, respectively. When the microbiome relationships from the first time point were added to the genomic relationships, the maximum prediction accuracy increased to 0.247 (from 0.216 when only the genomic relationship was used), which was achieved by giving the genomic relationships 10 times more weighting than the microbiome relationships. These accuracies were higher than the genomic, metabolomic, and microbiome relationship matrixes achieved alone when identical sets of animals were used.

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