Divergence of Nematocysts in Two Colour Morphs of the Intertidal Beadlet Anemone Actinia Equina

1998 ◽  
Vol 78 (3) ◽  
pp. 821-828 ◽  
Author(s):  
A. Louise Allcock ◽  
Phillip C. Watts ◽  
John P. Thorpe
Keyword(s):  
Morphological Plasticity ◽  
Biological Species ◽  
Gene Pools ◽  
Separate Species ◽  
Genetic Studies ◽  
Separate Gene ◽  
Considerable Debate ◽  
The Common ◽  
Colour Morphs ◽  
Different Tissues

In the common intertidal sea anemone Actinia equina (Cnidaria: Actiniaria) the morphological plasticity and lack of hard parts has caused considerable debate as to what constitutes a species. Over the last several years genetic studies have indicated that this ‘species’ consists of various separate gene-pools which appear to function as cryptic biological species. Conventional taxonomy has often concentrated on the use of a cnidome, the type, structure and number of nematocysts ('stinging’ cells). However, the usefulness of nematocysts to distinguish among various morphs of A. equina and other anthozoan species has recently been questioned. Here we describe the first detailed study of nematocyst differences between two well characterized genetically differentiated morphs with different coloured pedal discs. Measurements were taken from each type of nematocyst in five different tissues. Contrary to expectations, clear and significant nematocyst differences were found between Actinia with red or pink pedal discs and others with green to grey pedal discs. These findings support previous electrophoretic studies and suggest that quantitative descriptions of the cnidome may accurately identify separate species within other genera of Anthozoa.

Willughby's Buzzard: names and misnomers of the European Honey-buzzard (Pernis apivorus)

2018 ◽  
Vol 45 (1) ◽  
pp. 80-91 ◽  
Author(s):  
T. R. Birkhead ◽  
I. Charmantier ◽  
P. J. Smith ◽  
R. Montgomerie
Keyword(s):  
Accurate Description ◽  
Separate Species ◽  
Common Buzzard ◽  
Buteo Buteo ◽  
John Ray ◽  
The Common ◽  
Francis Willughby

The European Honey-buzzard (Pernis apivorus) was first accurately described and clearly distinguished from the Common Buzzard (Buteo buteo) by Francis Willughby and John Ray in their Ornithology, originally published in Latin in 1676. Alfred Newton's statement that Pierre Belon had described the species over a century earlier is not entirely correct, as Belon confused this honey-buzzard's features with those of the common buzzard and even appeared uncertain whether it was a separate species. One of Willughby's important contributions to ornithology was the identification and use of “characteristic marks” to distinguish and identify species, including those that distinguish the European Honey-buzzard from the Common Buzzard. Because Willughby provided the first accurate description of Pernis apivorus  – and because his contribution to ornithology has never been formally recognized –  we propose that the common name of the European Honey-buzzard be changed to Willughby's Buzzard.

THE EU SUGAR MARKET PROFILE AND ITS MAIN DRIVERS

2015 ◽  
Author(s):  
Lubos SMUTKA ◽  
Irena BENEŠOVÁ ◽  
Patrik ROVNÝ ◽  
Renata MATYSIK-PEJAS
Keyword(s):  
Market Failure ◽  
Current System ◽  
Quota System ◽  
Considerable Debate ◽  
Sugar Market ◽  
The Common ◽  
The One ◽  
Production Capacities ◽  
The Given ◽  
The Eu

Sugar is one of the most important elements in human nutrition. The Common Market Organisation for sugar has been a subject of considerable debate since its establishment in 1968. The European agricultural market has been criticized for its heavy regulations and subsidization. The sugar market is one of the most regulated ones; however, this will change radically in 2017 when the current system of production quotas will end. The current EU sugar market changed is structure during the last several decades. The significant number of companies left the market and EU internal sugar market became more concentrated. The aim of this paper is presentation characteristics of sugar market with respect to the supposed market failure – reduction in competition. The analysis also identifies the main drivers and determinants of the EU especially quota sugar market. In relation to paper’s aim the following results are important. The present conditions of the European sugar market have led to market failure when nearly 75 % (10 million tonnes) of the quota is controlled by five multinational companies only. These multinational alliances (especially German and French one) are also taking control over the production capacities of their subsidiaries. In most countries, this causes serious problems as the given quota is controlled by one or two producers only. This is a significant indicator of market imperfection. The quota system cannot overcome the problem of production quotas on the one hand and the demand on the other; furthermore, it also leads to economic inefficiency. The current EU sugar market is under the control of only Sudzucker, Nordzucker, Pfeifer and Langen, Tereos and ABF.

scholarly journals Comparative Analysis of In Vitro Responses and Regeneration between Diverse Bioenergy Sorghum Genotypes

Plants ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 248
Author(s):  
Barry Flinn ◽  
Savanah Dale ◽  
Andrew Disharoon ◽  
Stephen Kresovich
Keyword(s):  
Plantlet Regeneration ◽  
Induction Phase ◽  
Genetic Studies ◽  
Response Profiles ◽  
The Common ◽  
Parental Lines ◽  
Sorghum Genotypes ◽  
Better Than

Sorghum has been considered a recalcitrant plant in vitro and suffers from a lack of regeneration protocols that function broadly and efficiently across a range of genotypes. This study was initiated to identify differential genotype-in vitro protocol responses across a range of bioenergy sorghum parental lines and the common grain sorghum genotype Tx430 in order to characterize response profiles for use in future genetic studies. Two different in vitro protocols, LG and WU, were used for comparisons. Distinct genotype-protocol responses were observed, and the WU protocol performed significantly better for plantlet regeneration. Most bioenergy genotypes performed as well, if not better than Tx430, with Rio and PI329311 as the top regenerating lines. Genotypes displayed protocol-dependent, differential phenolic exudation responses, as indicated by medium browning. During the callus induction phase, genotypes prone to medium browning exhibited a response on WU medium which was either equal or greater than on LG medium. Genotype- and protocol-dependent albino plantlet regeneration was also noted, with three of the bioenergy genotypes showing albino plantlet regeneration. Grassl, Rio and Pink Kafir were susceptible to albino plantlet regeneration, with the response strongly associated with the WU protocol. These bioenergy parental genotypes, and their differential responses under two in vitro protocols, provide tools to further explore and assess the role of genetic loci, candidate genes, and allelic variants in the regulation of in vitro responsiveness in sorghum.

The genetic make-up of the European landraces of the common bean

2011 ◽  
Vol 9 (2) ◽  
pp. 197-201 ◽  
Author(s):  
S. A. Angioi ◽  
D. Rau ◽  
L. Nanni ◽  
E. Bellucci ◽  
R. Papa ◽  
...  
Keyword(s):  
Common Bean ◽  
Gene Pool ◽  
Chloroplast Microsatellites ◽  
Gene Pools ◽  
Mesoamerican Gene Pool ◽  
Hybridization Event ◽  
South Eastern Europe ◽  
Andean Type ◽  
The Common ◽  
African Sample

Here, we present a brief overview of the main studies conducted on the common bean (Phaseolus vulgaris L.) in Europe and other countries outside its centres of origin. We focus on the proportions of the Andean and Mesoamerican gene pools, and on the inter-gene pool hybridization events. In Europe, for chloroplast microsatellites, 67% of European germplasm is of Andean origin. Within Europe, interesting trends have been seen; indeed, the majority of the Andean type is found in the three macro-areas of the Iberian Peninsula, Italy and central-northern Europe, while, in eastern and south-eastern Europe, the proportion of the Mesoamerican type increased. On a local scale, the contribution of the Mesoamerican type is always low. On other continents, various situations are seen using different markers: in China and Brazil, the Mesoamerican gene pool prevails, while in an African sample, overall, both gene pools are equally represented, with differences in individual countries. The frequency of European bean genotypes deriving from at least one hybridization event was 44% with an uneven distribution. Interestingly, hybrids tend to have intermediate seed size in comparison with ‘pure’ Andean or Mesoamerican types. On other continents, very few hybrids are found, probably because of the different marker systems used.

Rheumatological manifestations of endocrine disorders

2013 ◽  
Author(s):  
Sanjeev Sharma ◽  
Gerry Rayman
Keyword(s):  
Population Studies ◽  
Endocrine Disorders ◽  
Genetic Studies ◽  
Comprehensive List ◽  
Clinical Presentations ◽  
Organ Systems ◽  
Musculoskeletal Manifestations ◽  
The Common ◽  
Clinical Conditions ◽  
Rheumatological Manifestations

There is considerable overlap of musculoskeletal manifestations of both rheumatological and endocrine disorders. Apart for the well-described autoimmune basis governing the aetiopathogenesis of clinical states pertaining to specific conditions affecting both systems, there is more recent evidence on the overlapping biology and genetics of these organ systems. Not uncommonly, endocrine manifestations can herald the initial presentation of rheumatological illnesses and the converse holds true for endocrinopathies. Rheumatologists and physicians alike need to be astutely aware of this overlap of symptomatology and also the physiology linking both groups of clinical conditions. This review discusses the common endocrine presentations associated with rheumatic illnesses in relation to newer information gleaned from population studies, genetic studies, and clinical presentations. A comprehensive list of rheumatological conditions found in endocrine states is also tabulated at the end.

Revision of the Scopula dubernardi species group: how many species? (Lepidoptera: Geometridae, Sterrhinae)

Zootaxa ◽  
2006 ◽  
Vol 1164 (1) ◽  
pp. 35
Author(s):  
PASI SIHVONEN ◽  
DIETER STÜNING
Keyword(s):  
Species Delimitation ◽  
Male Genitalia ◽  
Species Group ◽  
Female Genitalia ◽  
Immature Stages ◽  
Separate Species ◽  
The Common ◽  
Common Situation

The Palaearctic Scopula dubernardi species group (Lepidoptera: Geometridae) is revised on the basis of external and genitalic characters to include Scopula dubernardi (Oberthür, 1923) and Scopula segregata Prout, 1919. Lectotypes are designated for both species, which were described from more than one specimen without holotype designation. The species delimitation is based on small quantitative differences in the female genitalia, i.e., the degree of turn of the ductus bursae along its axis, and on external features. Furthermore, the recognition of the studied taxa as separate species is strengthened by the observation that they occur sympatrically and synchronously in two localities. Unlike the common situation in the genus Scopula, structures of the male genitalia were found uninformative in species delimitation. The length of right ceras on the 8th sternite of S. segregata was found to be polymorphic. Adults and genitalia of S. dubernardi and S. segregata are illustrated, along with the variation in external features and genitalia in both species. The biology and immature stages of both species are unknown.

Dihaploid induction ability of three clones of Solanum phureja (2n = 2x = 24) in interploidy cross with S. tuberosum (2n = 4x = 48)

2010 ◽  
Vol 58 (1) ◽  
pp. 49-54
Author(s):  
J. Panahandeh
Keyword(s):  
Male Fertility ◽  
Marker Gene ◽  
Seed Parent ◽  
Genetic Studies ◽  
Interploidy Crosses ◽  
Tuber Colour ◽  
The Common ◽  
Tetraploid Level ◽  
Pollen Shed ◽  
The Given

Potato, Solanum tuberosum L. (2n = 4x = 48), is an autotetraploid species, the breeding of which at the tetraploid level is complicated by tetrasomic inheritance. Dihaploids (2n = 2x = 24) from the tetraploid cultivated potato have great potential for breeding and genetic studies. The common method deployed to obtain potato dihaploids is to make interspecific-interploidy (4x × 2x) crosses between a tetraploid seed parent and special clones from the diploid S. phureja as pollinator. Pollinators carrying a marker gene have been used, but unfortunately, these clones were very weak, with rare flowering and low male fertility under the given conditions. To find a suitable pollinator, three clones were selected from S. phureja based on flowering, pollen shed and male fertility and were crossed with five cultivated tetraploid potatoes to evaluate their dihaploid induction ability. A total of 1529 interploidy crosses were made, resulting in 1116 berries and 1456 seeds. The progeny were divided into two groups based on stem, flower and tuber colour: hybrids and non-hybrids (putative dihaploids). Chromosome counting in non-hybrid genotypes detected 39 dihaploids. The clone phu 3 and cv. Picasso, with 12.1 and 10.7 dihaploids per 100 berries, respectively, were the best dihaploid inducer and seed parent for dihaploid production.

Laboratory hybridization in green lacewings (Neuroptera: Chrysopidae: Chrysoperla): evidence for genetic incompatibility

1993 ◽  
Vol 71 (2) ◽  
pp. 233-237 ◽  
Author(s):  
Marta Martínez Wells
Keyword(s):  
Hatching Success ◽  
Biological Species ◽  
Egg Laying ◽  
Postzygotic Isolation ◽  
Separate Species ◽  
Genetic Incompatibility ◽  
Second Stage ◽  
Behavioral Isolation ◽  
Two Generations ◽  
Chrysoperla Plorabunda

Courtship songs are an important reproductive barrier in lacewings of the genus Chrysoperla, so heterotypic matings should occur less readily than homotypic matings. In addition, if song morphs have become separate species, there may be some postzygotic isolation between song morphs. Two generations of crosses using sympatric P1 and P3 morphs of Chrysoperla plorabunda provide evidence for both hypotheses. In the first stage of the experiment, egg laying (an indication of mating success) was delayed by a week in heterotypic crosses compared with homotypic crosses, and hatching success of eggs from hybrid crosses was 16% lower than that from control crosses. In the second stage of the experiment, backcrosses involving P3 morph males or females were the least successful in mating. When pairs did mate, they did so a week later than in the other crosses. Thus, behavioral isolation delays heterotypic matings when females are not given a choice of mates. These results provide some genetic evidence that the song morphs of the C. plorabunda complex are biological species.

scholarly journals Genetic impact of gadoid culture on wild fish populations: predictions, lessons from salmonids, and possibilities for minimizing adverse effects

2006 ◽  
Vol 63 (2) ◽  
pp. 198-208 ◽  
Author(s):  
Dorte Bekkevold ◽  
Michael M. Hansen ◽  
Einar E. Nielsen
Keyword(s):  
Life History Traits ◽  
Wild Population ◽  
General Trend ◽  
Fish Populations ◽  
Gene Pools ◽  
Wild Populations ◽  
Genetic Studies ◽  
Hatchery Fish ◽  
Genetic Impact ◽  
Up Scaling

Abstract Little is known about the effects of ranched gadoids escaping into wild populations, and plans for substantial up-scaling of gadoid mariculture raise concerns about detrimental effects on local gene pools. Genetic studies from salmonid populations subjected to intentional or unintentional releases of hatchery-produced fish suggest that wild gene pools are affected by introgression, but that the genetic impact can be minor relative to expectations from the often substantial numbers of released hatchery fish. However, even if resilience to introgression is a general trend, wild population fitness is still predicted to be jeopardized by releases. In this paper, we review theoretical genetic effects of escapes of cultivated individuals and the empirical evidence for introgression effects, which are based mainly on salmonid studies. Based on knowledge of gadoid population structure and life history traits, we make predictions for effects of gadoid mariculture on wild populations and discuss approaches for monitoring and minimizing introgression effects.

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