Luca Dondini

Honey is primarily composed of sugars, along with various secondary components, including environmental DNA (eDNA) derived from all organisms directly or indirectly involved in its production process. Specifically, DNA of plant origin is mainly found in the pollen collected by honey bees from the same flowers where they collected nectar. The European chestnut ( Castanea sativa , Miller) is highly valued in beekeeping for its abundant nectar production. In this study, we gathered insights on the genetic variability of C. sativa by analyzing DNA extracted from 21 chestnut monofloral honey samples produced in four regions in Northern Italy. The DNA was amplified using six C. sativa microsatellite markers commonly used for genotyping chestnut tree genetic resources. All eDNA‐derived samples successfully amplified the microsatellite loci, showing a high level of genetic variability, with a total of 35 different alleles, averaging 23.95 ± 2.09 alleles per honey sample. Some unexpected and rare C. sativa alleles were also identified in several honey samples. Genetic diversity of C. sativa was evaluated using honey‐derived microsatellite fingerprints by categorizing honey samples based on their production region and comparing their profiles using the fixation index F _ST . The highest F _ST value was observed between honey samples from Emilia‐Romagna and Trentino‐Alto Adige regions, while the lowest F _ST value was between Veneto and Trentino‐Alto Adige samples. Cluster analysis and Principal Component Analysis using microsatellite data indicated distinct geographically defined groups corresponding to the honey production regions. The findings suggest that honey eDNA can be utilized to assess the genetic variability of chestnut accessions, aiding in determining the geographical origin of chestnut honey samples, thus indirectly supporting their geographic authentication.

ISHS International Symposium on Breeding and Effective Use of Biotechnology and Molecular Tools in Horticultural Crops Characterization of the genetic diversity of red-fleshed pear accessions from the Emilia-Romagna region

Climate change is deeply impacting the food chain production, lowering quality and yield. In this context, the international scientific community has dedicated many efforts to enhancing resilience and sustainability in agriculture. Italy is among the main European producers of several fruit trees; therefore, national research centers and universities undertook several initiatives to maintain the specificity of the ‘Made in Italy’ label. Despite their importance, fruit crops are suffering from difficulties associated with the conventional breeding approaches, especially in terms of financial commitment, land resources availability, and long generation times. The ‘new genomic techniques’ (NGTs), renamed in Italy as ‘technologies for assisted evolution’ (TEAs), reduce the time required to obtain genetically improved cultivars while precisely targeting specific DNA sequences. This review aims to illustrate the role of the Italian scientific community in the use of NGTs, with a specific focus on Citrus, grapevine, apple, pear, chestnut, strawberry, peach, and kiwifruit. For each crop, the key genes and traits on which the scientific community is working, as well as the technological improvements and advancements on the regeneration of local varieties, are presented. Lastly, a focus is placed on the legal aspects in the European and in Italian contexts.

The genus Pyrus is characterized by an S-RNase-based gametophytic self-incompatibility (GSI) system, a mechanism that promotes outbreeding and prevents self-fertilization. While the S-genotype of the most widely known pear cultivars was already described, little is known on the S-allele variability within local accessions. The study was conducted on 86 accessions encompassing most of the local Sicilian varieties selected for their traits of agronomic interest and complemented with some accessions of related wild species (P. pyrifolia Nakai, P. amygdaliformis Vill.) and some national and international cultivars used as references. The employment of consensus and specific primers enabled the detection of 24 S-alleles combined in 48 S-genotypes. Results shed light on the distribution of the S-alleles among accessions, with wild species and international cultivars characterized by a high diversity and local accessions showing a more heterogeneous distribution of the S-alleles, likely reflecting a more complex history of hybridization. The S-allele distribution was largely in agreement with the genetic structure of the studied collection. In particular, the “wild” genetic background was often characterized by the same S-alleles detected in P. pyrifolia and P. amygdaliformis. The analysis of the S-allele distribution provided novel insight into the contribution of the wild and international cultivars to the genetic background of the local Sicilian or national accessions. Furthermore, these results provide information that can be readily employed by breeders for the set-up of novel mating schemes.

This work investigated the genetic diversity of 134 Castanea sativa Mill. accessions present in the Italian region of Emilia-Romagna. Samples were taken from three collection fields (Granaglione, Zocca and Paloneta) in the Tuscan-Emilian Apennines. The accessions were analyzed by using 16 microsatellite markers (SSR). Genetic distances among accessions, calculated through the DICE coefficient, were used to construct an UPGMA cluster analysis. One major genotype (named “Marroni”) was identified across the three investigated collection fields; this variety corresponds to a sweet chestnut cultivar that has been propagated and widely diffused in the Emilia-Romagna region. Other genotypes were represented by different varieties of Italian chestnuts. The results of this study will be used to define and share guidelines for the characterization and varietal certification of the chestnut varieties in the Emilia-Romagna region.

ISHS II International Workshop on Floral Biology and S-Incompatibility in Fruit Species Data mining for apple S-RNase alleles in resequencing datasets

ISHS II International Workshop on Floral Biology and S-Incompatibility in Fruit Species Use of semi-compatible crosses in breeding for apple scab resistance