Search results for "Genetics"

2016

Sex differences in ageing rates and lifespan are common in nature, and an enduring puzzle for evolutionary biology. One possibility is that sex-specific mortality rates may result from recessive deleterious alleles in ‘unguarded’ heterogametic X or Z sex chromosomes (the unguarded X hypothesis). Empirical evidence for this is, however, limited. Here, we test a fundamental prediction of the unguarded X hypothesis in Drosophila melanogaster , namely that inbreeding shortens lifespan more in females (the homogametic sex in Drosophila ) than in males. To test for additional sex-specific social effects, we studied the lifespan of males and females kept in isolation, in related same-sex groups, …

Chironomus riparius(Diptera) genome sequencing reveals the impact of minisatellite transposable elements on population divergence

2016

AbstractActive transposable elements (TEs) may result in divergent genomic insertion and abundance patterns among conspecific populations. Upon secondary contact, such divergent genetic backgrounds can theoretically give rise to classical Dobzhansky-Muller incompatibilities (DMI), a way how TEs can contribute to the evolution of endogenous genetic barriers and eventually population divergence. We investigated whether differential TE activity created endogenous selection pressures among conspecific populations of the non-biting midgeChironomus riparius,focussing on aChironomus-specific TE, the minisatellite-likeCla-element, whose activity is associated with speciation in the genus. Using an …

The complete plastid genome of the middle Asian endemic of Stipa lipskyi (Poaceae)

2016

AbstractThe structure of the Stipa lipskyi (GenBank accession no. KT692644) plastid genome is similar to that of closely related Poaceae species: it has a total length of 137 755 bp, the base composition of the plastome is the following: A (30.7%), C (19.3%), G (19.4%) and T (30.5%). The S. lipskyi plastid genome contains 71 genes, excluding second IR region. A complete plastome sequence of S. lipskyi will help the development of primers for examining phylogeny and hybridization events in this taxonomically difficult genus.

Host infection history modifies co-infection success of multiple parasite genotypes.

2015

Co-infections by multiple parasite genotypes are common and have important implications for host-parasite ecology and evolution through within-host interactions. Typically, these infections take place sequentially, and therefore, the outcome of co-infection may be shaped by host immune responses triggered by previous infections. For example, in vertebrates, specific immune responses play a central role in protection against disease over the course of life, but co-infection research has mostly focused on previously uninfected individuals. Here, we investigated whether sequential exposure and activation of host resistance in rainbow trout Oncorhynchus mykiss affects infection success and inte…

Repeated evolution of camouflage in speciose desert rodents

2017

AbstractThere are two main factors explaining variation among species and the evolution of characters along phylogeny: adaptive change, including phenotypic and genetic responses to selective pressures, and phylogenetic inertia, or the resemblance between species due to shared phylogenetic history. Phenotype-habitat colour match, a classic Darwinian example of the evolution of camouflage (crypsis), offers the opportunity to test the importance of historical versus ecological mechanisms in shaping phenotypes among phylogenetically closely related taxa. To assess it, we investigated fur (phenotypic data) and habitat (remote sensing data) colourations, along with phylogenetic information, in t…

Discovery of a Major QTL Controlling Trichome IV Density in Tomato Using K-Seq Genotyping

2021

[EN] Trichomes are a common morphological defense against pests, in particular, type IV glandular trichomes have been associated with resistance against different invertebrates. Cultivated tomatoes usually lack or have a very low density of type IV trichomes. Therefore, for sustainable management of this crop, breeding programs could incorporate some natural defense mechanisms, such as those afforded by trichomes, present in certain Solanum species. We have identified a S. pimpinellifolium accession with very high density of this type of trichomes. This accession was crossed with a S. lycopersicum var. cerasiforme and a S. lycopersicum var. lycopersicum accessions, and the two resulting F2 …

In vitro storage of plum germplasm by slow growth

2015

Gianni S., Sottile F. (2015): In vitro storage of plum germplasm by slow growth . Hort. Sci. (Prague), 42: 61–69. In this study, in vitro slow growth storage was investigated in four cultivars of two Sicilian (Southern Italy) plum species (Prunus domestica L. and Prunus cerasifera Ehrh. – two genotypes each). Established shoot cultures were preserved at 4°C in the dark in a Murashige and Skoog basal medium containing one of two different concentrations of sucrose (20 and 30 g/l) and with or without growth regulators. We tested the effects of cold storage, genotype and media on survival and re-growth capacity of explants after 3, 6, 9 and 12 months of storage. Effective minimal growth under …

S-genotype identification, genetic diversity and structure analysis of Italian sweet cherry germplasm

2017

In this study, 186 local sweet cherry accessions from 12 Italian regions, plus eight reference accessions, were analysed for the first time, using 13 microsatellite markers. Moreover, their S-incompatibility genotypes were identified with consensus primers for the S-RNase and SFB genes. A total of 161 unique genotypes were found; 18 groups of synonyms, along with the discovery of cases of misidentification. The average number of alleles per locus was 9.7, the mean expected heterozygosity (He) was 0.63, the mean observed heterozygosity (Ho) was 0.65 and the mean polymorphic information content (PIC) was 0.58. The structure analysis revealed the presence of six populations, which reflected in…

Towards a Joint International Database: Alignment of SSR Marker Data for European Collections of Cherry Germplasm

2021

International audience; The objective of our study was the alignment of microsatellite or simple sequence repeat (SSR) marker data across germplasm collections of cherry within Europe. Through the European Cooperative program for Plant Genetic Resources ECPGR, a number of European germplasm collections had previously been analysed using standard sets of SSR loci. However, until now these datasets remained unaligned. We used a combination of standard reference genotypes and ad-hoc selections to compile a central dataset representing as many alleles as possible from national datasets produced in France, Great Britain, Germany, Italy, Sweden and Switzerland. Through the comparison of alleles c…

Genetic characterization of an almond germplasm collection and volatilome profiling of raw and roasted kernels

2021

AbstractAlmond is appreciated for its nutraceutical value and for the aromatic profile of the kernels. In this work, an almond collection composed of 96 Sicilian accessions complemented with 10 widely cultivated cultivars was phenotyped for the production of volatile organic compounds using a proton-transfer time-of-flight mass spectrometer and genotyped using the Illumina Infinium®18 K Peach SNP array. The profiling of the aroma was carried out on fresh and roasted kernels enabling the detection of 150 mass peaks. Sixty eight, for the most related with sulfur compounds, furan containing compounds, and aldehydes formed by Strecker degradation, significantly increased during roasting, while …