Search results for "Breeding"
showing 10 items of 475 documents
Utilizzo dell’embriogenesi gametica per il miglioramento genetico dei Citrus.
2013
Ottenimento di triploidi mediante coltura in vitro di semi di Citrus clementina Hort. ex Tan., cv. Monreal Bianco e Monreal Verde.
2011
STUDY ON GAMETIC EMBRYOGENESIS VIA IN VITRO ANTHER AND ISOLATED MICROSPORE CULTURE IN FRUIT CROPS
2014
Fruit breeding is mainly based on both conventional (hybridization, mutation and selection) or biotechnological methods (somatic hybridization, genetic transformation and haploid production). The genetic improvement through the conventional methods is limited by many factors such as fruit trees long juvenile period, high heterozygosity, large size and sexual incompatibility. Haploids and doubled haploids, obtained through gametic embryogenesis have a potential use in fruit crops genetic improvement. The change of the microspores fate from the normal gametopytic pathway towards the sporophytic induction is affected by numerous factors. Genotype, medium composition and stress were considered …
La biodiversità delle formazioni naturali e seminaturali in Sicilia: cambiamenti e ipotesi di gestione
2009
A large part of the natural formations that occupied the surface of Sicily have disappeared because of heavy transformations beginning from the ancient time. These transformations have provoked the disappearance of entire communities plants and animals but the entity of these modifications can be only partially appreciated or assumed on the base of fragmentary data. Scope of this study is to evaluate changes in plant and animal communities in the course of the centuries. Until the end of the nineteenth century on the whole an equilibrium was established in the Island. The agricultural activity had surely changed the proportions of the habitats contributing to the spread of open spaces commu…
Reproductive characteristics and differential response to seasonal temperatures of Blue and Great Tits (Cyanistes caeruleus & Parus major) in three n…
2011
The breeding ecology of the Blue Tit (Cyanistes caeruleus) and Great Tit (Parus major) was studied for 18 years in three different neighbouring habitats in Sicily, comprising oakwoods, reforested pine and a reforested mix of pine and broad-leaved trees. Both Blue and Great Tits laid eggs up to two weeks earlier in oakwoods than in the reforested areas. Our results indicate a statistically greater breeding success for both species in the oakwoods compared to reforested habitats, with the mixed reforested habitat having a greater success than that of reforested pine habitat. We also correlated reproductive characteristics with local air temperature to verify if the laying date of tits advance…
High-density SNP markers elucidate the genetic divergence and population structure of Noticiana sheep breed in the Mediterranean context
2023
Among livestock species, sheep have played an early major role in the Mediterranean area. Italy has a long history of sheep breeding and, despite a dramatic contraction in numbers, still raise several local populations that may represent a unique source of genetic diversity. The Noticiana is a breed of the south-eastern part of Sicily appreciated both for its dairy products and for its resistance to harsh environment. In this study, the high-density Illumina Ovine SNP600K BeadChip array was used for the first genome-wide characterization of 48 individuals of Noticiana sheep to investigate its diversity, the genome structure and the relationship within the context of worldwide and Italian br…
Using of SNP markers to estimate inbreeding, coancestry and effective population size in Sicilian cattle breeds
2014
Maintaining the highest levels of genetic diversity and limiting the increase in inbreeding is the premise of most conservation programs. The aim of this work was to estimate the inbreeding (F), coancestry (f) and effective population size (Ne) in two Sicilian cattle breeds, Cinisara (CIN) and Modicana (MOD). Rate of molecular inbreeding and coancestry were used to estimate the Ne. A total of 144 animals were genotyped using the Illumina Bovine SNP50K v2 BeadChip. The average molecular F and f coefficients were 0.68±0.024 and 0.67±0.03 in CIN and 0.69±0.020 and 0.70±0.03 in MOD cattle breeds, respectively. The results were not unexpected considering the reduced number of reared animals and …
High-density single nucleotide polymorphism markers reveal the population structure of 2 local chicken genetic resources
2023
Italy counts a large number of local chicken populations, some without a recognized genetic structure, such as Val Platani (VPL) and Cornuta (COS), which represent noteworthy local genetic resources. In this study, the genotype data of 34 COS and 42 VPL, obtained with the Affymetrix Axiom600KChicken Genotyping Array, were used with the aim to investigate the genetic diversity, the runs of homozygosity (ROH) pattern, as well as the population structure and relationship within the framework of other local Italian and commercial chickens. The genetic diversity indices, estimated using different approaches, displayed moderate levels of genetic diversity in both populations. The identified ROH h…
A genome-wide perspective on the population structure of Italian cattle breeds
2018
Despite the growing diffusion of cosmopolite specialized breeds, several autochthonous cattle breeds and populations are still bred in Italy. The aim of this study was to provide a high-resolution picture of the genome-wide diversity and population structure of Italian local cattle breeds using medium-density genome-wide SNP markers. After data editing, the dataset included 800 samples from 32 breeds that were genotyped for 31 013 SNPs. For several breeds we observed a low level of polymorphism and genetic diversity, that together with the small effective population sizes confirmed threat of extinction. According to the runs of homozygosity analysis, evidence of recent inbreeding was strong…