Seed cryopreservation of Fraxinus angustifolia Vahl

Fraxinus angustifolia is used for afforestation and for production of both valuable timber and manna, a substance with pharmacological applications. The aim of this research was to establish the optimized condition for cryopreservation of F. angustifolia seeds, in order to protect the germplasm of this species. Germination percentage and mean time of germination of non-treated seeds (control) and liquid nitrogen-treated seeds were established in water or in 10-6 M gibberellic acid (GA3). The seeds could be cryopreserved with 3% of moisture content (MC) and germinated easily in water (70.0 ± 5.0%), while seeds cryopreserved with 6% MC showed a physiological dormancy. This state could be efficiently removed by addition of GA3, which increased germination to 76.0 ± 2.4%. Liquid nitrogen did not impair embryo viability, allowing a successful cryopreservation of seeds. The results are particularly useful for both germplasm conservation programs and in narrow leaved ash nurseries.Keywords: Fraxinus angustifolia, germination, germplasm conservation, seed cryopreservationAfrican Journal of Biotechnology Vol. 12(16), pp. 1930-193

Genetic diversity in Sicilian populations of Quercus ilex (Fagaceae)

Recent studies on the genetic structure of the Italian populations of Quercus ilex demonstrated their high diversity, particularly in the Sicilian metapopulation. In order to check if the holm oak stands in the mountains of NW Sicily could have some relationship with Q. ilex subsp. bal- lota (distributed in Spain and NW Africa), 26 specimens from the Sicilian most distinctive Q. ilex populations have been compared with some representative populations of the Italian Peninsula, North Africa and Spain, by means of the ISSR technique. Even if the results are too preliminary to confirm or reject the initial hypothesis, they confirmed an high level of genetic variability, well distributed among the analyzed specimens. In particular, the metapopulations from the Sicilian mountains (Quacella, Vallone Canna) revealed some genetic affinity with those of the Moroccan mountains (Marrakech/Oukaimeden and Ifrane). These populations, on their turn, resulted to be quite distant from the sample from SE-Spain (Sierra de Javalambre). Moreover, a certain genetic distance has been detected from the comparison of the mountain populations of Sicily with those of coastal sites of this Island (Scopello, Castellammare) and Capri (Villa Jovis)

Diversity Assessment and DNA-Based Fingerprinting of Sicilian Hazelnut (Corylus avellana L.) Germplasm

The characterization of plant genetic resources is a precondition for genetic improvement and germplasm management. The increasing use of molecular markers for DNA-based genotype signature is crucial for variety identification and traceability in the food supply chain. We collected 75 Sicilian hazelnut accessions from private and public field collections, including widely grown varieties from the Nebrodi Mountains in north east Sicily (Italy). The germplasm was fingerprinted through nine standardized microsatellites (SSR) for hazelnut identification to evaluate the genetic diversity of the collected accessions, validating SSR discrimination power. We identified cases of homonymy and synonymy among acquisitions and the unique profiles. The genetic relationships illustrated by hierarchical clustering, structure, and discriminant analyses revealed a clear distinction between local and commercial varieties. The comparative genetic analysis also showed that the Nebrodi genotypes are significantly different from the Northern Italian, Iberian, and Turkish genotypes. These results highlight the need and urgency to preserve Nebrodi germplasm as a useful and valuable source for traits of interest employable for breeding. Our study demonstrates the usefulness of molecular marker analysis to select a reference germplasm collection of Sicilian hazelnut varieties and to implement certified plants’ production in the supply chain

Preparation and Characterization of Inulin Coated Gold Nanoparticles for Selective Delivery of Doxorubicin to Breast Cancer Cells

A novel folate-targeted gold-based nanosystem for achieving selectivity towards folate receptor (FR) positive cells is proposed, by virtue of the fact that the FR is a molecularly targeted entity overexpressed in a wide spectrum of solid tumors. A new inulin-folate derivative (INU-FA) has been synthesized to act as coating agent for 40 nm gold nanoparticles. The obtained polymer-coated gold nanoparticles (Au@INU-FA) were characterized in terms of hydrodynamic radius, shape, zeta potential, and aqueous stability and were loaded with doxorubicin (Au@INU-FA/Doxo). Its release capability was tested in different release media. The selectivity of Au@INU-FA/Doxo system towards FRs-positive cancer cells was proved by the differences in the quantitative uptake using human breast cancer MCF7 as FR-positive cells and 16HBE epithelial as noncancer cell line. Furthermore, the folate-mediated uptake mechanism was studied by FRs-blocking experiments. On the whole Au@INU-FA/Doxo was able to be preferentially internalized into MCF7 cells proving a folate-mediated endocytosis mechanism which allowed a higher and selective cytotoxic effect towards cancer cells. The cytotoxicity profile was evaluated on both cancer and noncancer cell lines, displaying that folate-mediated targeting implied advantageous therapeutic effects, such as amplified drug uptake and increased anticancer activity towards MCF7 cancer cells

Effects of ageing on peroxidase activity and localization in radish ( Raphanus sativus L.) seeds

Peroxidase activity was assayed in crude extracts of integument, cotyledons and embryo axis of radish seeds, deteriorated under accelerated ageing conditions. Over five days of ageing, in which germination decreased from 100 to 52%, the enzyme activity in integument was higher than that in other seed parts, increasing in the first days of ageing and then decreasing sharply in extremely aged seeds. Polyacrylamide gel electrophoresis analysis showed four peroxidase isoenzymes with MM of 98, 52.5, 32.8 and 29.5 kDa in the embryo axis of unaged seeds, and only the 32.8 and 29.5 kDa MM isoforms in the integument and cotyledons. In these parts of the seed, only the 29.5 kDa MM isoenzyme increased in activity in early days of ageing and decreased thereafter. In the embryo axis, the 29.5 kDa MM isoenzyme activity increased slowly in the first day of ageing, while the 98 and 52.5 kDa MM isoenzyme activities disappeared. A cytochemical localization of peroxidase activity in the various tissues showed that main differences between unaged and extremely aged seeds occurred in the embryo axis

Long-range transport of beech (Fagus sylvatica L.) pollen to Catalonia (north-eastern Spain)

Local and long-range transport of beech (Fagus sylvatica) pollen was analysed by using 23-year data (1983-2007) at six stations in Catalonia, Spain, and numerical simulations. Back trajectories and synoptic meteorology indicated a consistent north European provenance during beech pollen peak days. Specifically, the area from northern Italy to central Germany was the most probable source, as indicated by a source-receptor model based on back trajectories. For the event with the highest pollen levels (17 May 2004), back trajectories indicated a source in the Vosges (NE France) and the Schwarzwald (SW Germany) regions. By applying a mesoscale model (MM5) to this event, pollen transport could be further refined, allowing its entrance to Catalonia through the lower easternmost pass of the Pyrenees (the Alberes pass, 500 m a.s.l.) to be described. Hourly counts of Fagus pollen allowed the timing of pollen arrival during this episode to be matched with the model results regarding the above-mentioned passage. This study may help to interpret some results of modern beech genetic diversity and contribute to the understanding of paleopalynological records by taking long-range transport into consideration