Renzo Torricelli

Structure of genetic diversity in Olea europaea L. cultivars from central Italy

The olive is considered one of the most important fruit crops of the Mediterranean basin where it shows a wide range of variability, with about 2,000 cultivars. Italy, with about 500 cultivars, plays a fundamental role. The ability to discriminate olive cultivars and estimate genetic variability are important factors in better management of genetic resources and in helping to understand how genetic diversity is partitioned among cultivars. The two main objectives of the present investigation were to evaluate the identity of cultivars grown in Abruzzo region, central Italy, and to study their genetic structure. We applied amplified fragment length polymorphism (AFLP) methodology on 84 genotypes belonging to the most relevant and oldest varieties cultivated in Abruzzo and on six unknown genotypes. The information content of data was evaluated using the Marker Ratio index and the Polymorphic Index Content. Moreover, STRUCTURE software was used to investigate the genetic population structure. The analysis enabled us to clearly distinguish eight cultivars within seven clusters. Additionally, one cluster was found to have various minor cultivars and showed a relatively high level of diversity. The partitioning of genetic diversity showed that the largest amount of molecular variance was within groups. Our data suggest that both sexual and clonal propagation have played an important role in the evolution of olive cultivars. In our hypothesis, some ancestral population spread in central Italy with a relevant role of seed propagation, followed by a selection of superior clones from which more traditional varieties originated. In a few cases, hybridization should be taken into consideration to explain the diffusion of recently developed cultivars.

Characterization of the lentil landrace Santo Stefano di Sessanio from Abruzzo, Italy

In the world lentil is grown on more than 3 million hectares and is one of the most important, low-cost, food source of protein. In Italy lentil has been cultivated since ancient times, but in the last decades its cultivation has been confined to marginal areas, small islands and hilly, mountainous areas of central and southern Italy. Local varieties are still common and are often greatly appreciated for their taste and cooking qualities. Several accessions from the Santo Stefano di Sessanio area, Abruzzo Region, were collected and phenotypically and genotypically characterized in order to look for the existing variability within and between populations. Image analysis of seeds was also used. Populations grown in Santo Stefano di Sessanio and in the neighbouring area basically share most of their characteristics. However, some of the accessions anonymously gathered from the local market were shown to be different from those collected from farmers. The paper reports and discusses how this local product needs be characterized and promoted in order to avoid fraud that could negatively affect the local economy and put valuable, adapted, genetic resources at risk of erosion.

Enhancing legume ecosystem services through an understanding of plant–pollinator interplay

Legumes are bee-pollinated, but to a different extent. The importance of the plant–pollinator interplay (PPI), in flowering crops such as legumes lies in a combination of the importance of pollination for the production service and breeding strategies, plus the increasing urgency in mitigating the decline of pollinators through the development and implementation of conservation measures. To realize the full potential of the PPI, a multidisciplinary approach is required. This article assembles an international team of genebank managers, geneticists, plant breeders, experts on environmental governance and agro-ecology, and comprises several sections. The contributions in these sections outline both the state of the art of knowledge in the field and the novel aspects under development, and encompass a range of reviews, opinions and perspectives. The first three sections explore the role of PPI in legume breeding strategies. PPI based approaches to crop improvement can make it possible to adapt and re-design breeding strategies to meet both goals of: (1) optimal productivity, based on an efficient use of pollinators, and (2) biodiversity conservation. The next section deals with entomological aspects and focuses on the protection of the “pest control service” and pollinators in legume crops. The final section addresses general approaches to encourage the synergy between food production and pollination services at farmer field level. Two basic approaches are proposed: (a) Farming with Alternative Pollinators and (b) Crop Design System.

Genetic analysis of the species of sigara s. str. (Heteroptera, Corixidae) in the Italian Peninsula

Abstract The genetic differences in three populations of Sigara s. str. belonging to S. striata, S. dorsalis, and S. basalis, distributed in northern (Veneto, South Tyrol) and central (Umbria, Molise) Italy, were assayed by horizontal starch electrophoresis. Adult specimens were examined. Twelve enzymes were assayed, eight of which gave satisfactory results. Five of the eight alloenzymes were further investigated to differentiate the three species: phos‐phoglucomutase (Pgm‐1, Pgm‐2), esterase (Est‐1, Est‐2, Est‐3), su‐peroxide dismutase (Sod‐1, Sod‐2), phosphoglucose isomerase (Pgi‐1, Pgi‐2), isocitrate dehydrogenase (Idh) coding for 10 studied loci. A total of 208 adults of the three taxa (142 for S. basalis, 49 for 5. dorsalis, and 17 for 5. striata) were analysed. Neis unbiased genetic distances were calculated and values between congeneric species ranged from 0.009 to 0.25, as illustrated in a phenogramme constructed by the unweighted pair‐group cluster analysis method. Sigara basalis presented the h...

Differentiation and structure of an Italian landrace of celery (Apium graveolens L.): inferences for on farm conservation

The “Sedano Nero di Trevi” (Black Celery from Trevi) is a landrace grown in Umbria (Italy) at risk of extinction. A morpho-physiological and molecular characterisation of the landrace and a detailed investigation of its cultural and cultivation context were carried out with the aim of facilitating a request for a quality mark, implement in situ (on farm) conservation schemes that are being developed in Italy and register the landrace in the European common catalogue of ‘conservation varieties’. These actions can help the landrace survive. Six farmer populations of the landrace and four élite varieties were characterised for thirteen morpho-physiological traits and nine AFLP primer combinations. The “Sedano Nero” farmer populations were better performers than élite varieties for important agronomic traits, such as yield, under the local agronomic conditions. Both morpho-physiological traits and molecular markers clearly distinguished the landrace from the élite cultivars. In addition, a structure was detected in the landrace with farmer populations being characterised by specific alleles. These results are discussed in connection with the local seed system and possible in situ conservation strategies for landraces.

Characterization and phylogenetic analysis of ancient Italian landraces of pear

Pear is one of the oldest fruit tree crops and the third most important temperate fruit species. Its domestication took place independently in the Far East (China) and in the Caucasus region. While the origin of Eastern Asian cultivars is clear, that of European cultivars is still in doubt. Italy has a wealth of local varieties and genetic resources safeguarded by several public and private collections to face the erosion caused by the introduction of improved varieties in specialized orchards. The objectives of the present study were: (i) to characterize the existing germplasm through nuclear (SSR) and (ii) to clarify the genetic divergence between local and cultivated populations through chloroplast DNA (cpDNA) markers in order to provide insights into phylogenetic relationships of Pyrus spp. For this reason, 95 entries from five different germplasm collections, including nine European, Mediterranean and Eastern Asian species, were analyzed, and the intergenic accD-psaI sequences were compared to the worldwide distributed dataset encompassing a total of 298 sequences from 26 different Pyrus species. The nine nuclear SSRs were able to identify a total of 179 alleles, with a loci polymorphism P = 0.89. Most of the variation (97%) was found within groups. Five accessions from different sources were confirmed to be the same. Eight out of 20 accessions of unknown origin were identified, and six synonyms were detected. Locus NH030a was found to be monomorphic in all the cultivated accessions and in reference species interfertile with P. communis, leading to hypothesize selection pressures for adaptation to cultivation. The cpDNA sequences of the 95 accessions were represented by 14 haplotypes, six of which (derived from P. communis, P. cossonii and P. ussuriensis) are recorded here for the first time and may suggest the ancient origin of some local varieties. The network analysis of the 298 cpDNA sequences allowed two different haplogroups, Eastern and Western Eurasia, to be defined, supporting recent views of a clear division between Occidental and Oriental species. By combining the results from nuclear and uniparental markers, it was possible to better define many unknown accessions.

A methodological approach to identify agro-biodiversity hotspots for priority in situ conservation of plant genetic resources

Agro-biodiversity is seriously threatened worldwide and strategies to preserve it are dramatically required. We propose here a methodological approach aimed to identify areas with a high level of agro-biodiversity in which to set or enhance in situ conservation of plant genetic resources. These areas are identified using three criteria: Presence of Landrace diversity, Presence of wild species and Agro-ecosystem ecological diversity. A Restrictive and an Additive prioritization strategy has been applied on the entire Italian territory and has resulted in establishing nationwide 53 and 197 agro-biodiversity hotspots respectively. At present the strategies can easily be applied at a European level and can be helpful to develop conservation strategies everywhere.

Perspectives and Challenges of Italian Catalogue of Herbage Varieties

In Mediterranean countries forage crops and temporary grasslands are the most important supply even if severe moisture stress is common. In Italy, forage systems are various and differently located from North to South of the mainland due to strong influence by rainfall distribution. Grasses and grazing cover 3.4 million ha of Italian utilized agricultural area (UAA) while alternated grassland and grass meadows cover 1.9 million ha. Most of grasslands are located in hilly and mountainous areas and are important for reducing erosion. Italy has a great longitudinal extension which accounts for a great variety of climate systems and soils: the northern regions have a humid subtropical climate and differ greatly from the south part that fits the Mediterranean climate profile. During the last 100/150 years the Italian climate has become warmer and drier showing an increase of erratic precipitation intensity. The future of breeding of forage grasses and legumes should be focused on higher nutrient use efficiencies and increased sustainability. New applications of genomics and bioinformatics will allow advanced breeding strategies. Over the past 15 years breeders have displayed a constant interest in forage species while a greater interest has risen in turfgrass varieties. Seed production of Italian herbages does not cover the requirements of the market. More specific value for cultivation and use (VCU) tests might be an effective means to improve the screening of candidate varieties. The goal is the selection of varieties able to withstand the stress of climate change, have better water and nitrogen use efficiency and resilience of vegetation cover.