Search results for "Germ"
showing 10 items of 3358 documents
Molecular Analysis of the Official Algerian Olive Collection Highlighted a Hotspot of Biodiversity in the Central Mediterranean Basin
2020
Genetic diversity and population structure studies of local olive germplasm are important to safeguard biodiversity, for genetic resources management and to improve the knowledge on the distribution and evolution patterns of this species. In the present study Algerian olive germplasm was characterized using 16 nuclear (nuSSR) and six chloroplast (cpSSR) microsatellites. Algerian varieties, collected from the National Olive Germplasm Repository (ITAFV), 10 of which had never been genotyped before, were analyzed. Our results highlighted the presence of an exclusive genetic core represented by 13 cultivars located in a mountainous area in the North-East of Algeria, named Little Kabylie. Compar…
Stress integrated tests and cytological analyses reveal Brassica villosa subsp. drepanensis seed quality decrease upon long-term storage
2016
Under stress integrated germination test (SIGT), seeds undergo osmo-saline stresses, which enable to detect differences in vigour of long-term stored seeds with high germination percentage (G%). The quality of Brassica villosa subsp. drepanensis seeds stored in a genebank (at -20°C for 16 years) was compared with seeds at harvest by standard germination tests (GT), SIGT and cytogenetic analysis. No differences were detected in G% and mean germination time under GT. Conversely, SIGT performed with NaCl -0.9MPa osmotic potential did not influence G% at harvest but reduced that of stored seeds, SIGT at -1.4MPa reduced G% of both. Cytogenetic analysis showed reduction of mitotic index, appearan…
Blattella germanica displays a large arsenal of antimicrobial peptide genes
2020
Defence systems against microbial pathogens are present in most living beings. The German cockroach Blattella germanica requires these systems to adapt to unhealthy environments with abundance of pathogenic microbes, in addition to potentially control its symbiotic systems. To handle this situation, four antimicrobial gene families (defensins, termicins, drosomycins and attacins) were expanded in its genome. Remarkably, a new gene family (blattellicins) emerged recently after duplication and fast evolution of an attacin gene, which is now encoding larger proteins with the presence of a long stretch of glutamines and glutamic acids. Phylogenetic reconstruction, within Blattellinae, suggests …
Unraveling Salt Tolerance in Halophytes: A Comparative Study on Four Mediterranean Limonium Species with Different Geographic Distribution Patterns
2017
[EN] We have performed an extensive study on the responses to salt stress in four related Limonium halophytes with different geographic distribution patterns, during seed germination and early vegetative growth. The aims of the work were twofold: to establish the basis for the different chorology of these species, and to identify relevant mechanisms of salt tolerance dependent on the control of ion transport and osmolyte accumulation. Seeds were germinated in vitro, in the presence of increasing NaCl concentrations, and subjected to ¿recovery of germination¿ tests; germination percentages and velocity were determined to establish the relative tolerance and competitiveness of the four Limoni…
Maritime Pine Pinus Pinaster Aiton
2018
Maritime pine (Pinus pinaster Aiton) is the most abundant conifer in the Mediterranean basin. Currently, maritime pine is considered to be a model conifer species for study of the adaption responses to drought stress from a genomics approach. In this context, the availability of protocols that allow not only mass vegetative propagation of selected families or genotypes, but also facilitate the functional analyses needed to verify and further to study the effects of candidate genes are necessary. Here we describe an improved protocol to generate maritime pine plants through somatic embryogenesis from immature megagametophytes. Accurate procedures for explant preparation, somatic embryo induc…
New Approaches to Optimize Somatic Embryogenesis in Maritime Pine
2019
Maritime pine (Pinus pinaster Aiton) is a coniferous native of the Mediterranean basin. Because of its adaptability to a wide range of environmental conditions, the species have become a model for studies in coniferous forest management and functional genomics. Somatic embryogenesis (SE) has been so far, the preferred biotechnological strategy for maritime pine breeding programs initiated at the middle-end of the 20th century. To overcome the limitations of the induction and maturation phases in maritime pine SE, we analyzed the possible maternal influence on the embryogenic capability of megagametophytes from controlled crosses, as well as the effect of the temperature and water availabili…
In vitro propagation of the relict laperinne’s olive (Olea europaea L. subsp. laperrinei)
2017
Olea europaea L. subsp. laperrinei (Oleaceae) is an endemic taxon of the mountainous regions of central Sahara, consisting of currently fragmented and small relict populations. The tree can propagate vegetatively or by seed, but no recent natural regeneration was observed in the Algerian massive populations, some of which are considered threatened with extinction. Sterile triploid individuals were also identified in some populations showing increasing vigour. As a result of its long persistence and despite its rarity, the Laperrine's olive is an iconic component of Saharan mountain ecosystems. The aim of this study is to develop an efficient micropropagation protocol for both diploid and tr…
Morphological and molecular variability within the fig cultivar 'Dottato' in the Italian protected designation origin area "fichi di Cosenza"
2017
The morphological and molecular diversity among fig accessions of 'Dottato', found in the PDO "Fichi di Cosenza" area was studied by evaluating 24 morphological traits and by genotyping with 18 microsatellite markers. The microsatellite allelic profiles among the putative clones of 'Dottato' indicated a moderate genetic variability, discriminating unambiguously most of the accessions. Only two groups of identity were found. The average expected and observed heterozygosity were 0.43 and 0.62, respectively. The mean polymorphic information content (PIC) was 0.4, varying from 0.08 (LMFC26) to 0.067 (FCUP 38-6). The morphological clustering allowed the distinction of all genotypes. Some genotyp…
Blackgrass (Alopecurus myosuroides Huds.) seed dispersal from a single plant and its consequences on weed infestation
2001
Blackgrass (Alopecurus myosuroides Huds.) seed dispersal from single mother-plants was studied in two experiments. For the first experiment, eight blackgrass plants of different heights and number of ears were produced in a greenhouse with the help of different in sowing densities and nitrogen nutrition levels. At the beginning of seed shedding, the plants were placed outside, and seeds were gathered daily. Daily seed dispersal was analysed by fitting a Weibull equation to the number of seeds as a function of distance to the mother-plant. The second experiment was carried out in a field comprising winter barley and spring barley plots as well as bare soil. In each of these three parts, two …
The Bonobo-DialiumPositive Interactions: Seed Dispersal Mutualism
2013
A positive interaction is any interaction between individuals of the same or different species (mutualism) that provides a benefit to both partners such as increased fitness. Here we focus on seed dispersal mutualism between an animal (bonobo, Pan paniscus) and a plant (velvet tamarind trees, Dialium spp.). In the LuiKotale rainforest southwest of Salonga National Park, Democratic Republic of Congo, seven species of the genus Dialium account for 29.3% of all trees. Dialium is thus the dominant genus in this forest. Dialium fruits make up a large proportion of the diet of a habituated bonobo community in this forest. During the 6 months of the fruiting season, more than half of the bonobos' …