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The genetic variability among 181 fig (Ficus carica L.) accessions found in small farms located in Campania, Basilicata, Apulia, Calabria and Sicily was investigated analysing the polymorphism of 18 simple sequence repeat (SSR) markers. The SSR analysis revealed a large genetic diversity among accessions. A total of 117 alleles were detected with a mean of 6.5 locus-1. The average expected (He) and observed heterozygosity (Ho) were 0.56 and 0.66, respectively. The mean polymorphic information content (PIC) was 0.51, suggesting a significant molecular diversity among the fig accessions taken into consideration. The UPGMA cluster analysis discriminated 174 genotypes and allowed to find 8 groups of identity. The genotype ‘Bianca di agosto’ was an “outgroup”. This study showed groups of fig accessions matching with their geographic or cultivation area, but also many genotypes, especially from Campania, with uneven distribution. The research evidenced the richness of the available fig genetic resources in Southern Italy, resolved cases of synonymies and homonymies and helped to characterize fig accessions, an important preliminary work for establishing core collections.

For a considerable period of time chestnuts were a fundamental source of food and economy for the people in the Aspromonte area. After decades in which chestnut cultivation has been neglected as a result of depopulation in mountainous zones, the production capacity in this area has reduced resulting in an erosion of the native germplasm. A survey has been carried out to improve the knowledge about the chestnut germplasm present in this area and to evaluate its qualities with the objective of preserving native genetic resources, safeguarding them from genetic erosion phenomenon and individuating local genotypes of market value which could be used to promote a re-launch of local chestnut cultivation. The research, which was carried out in 2008 on the western slopes of the Aspromonte, has led to the identification of 38 genotypes. The germplasm which was individuated has a considerable rate of variability in that it has different phenological and morphological characteristics. Overall, the 38 genotypes have a ripening period extending from the last 10 days of September until the end of October. With regard to the valuable characteristics of the nuts, the genetic material which was analysed was overall found to be of market value. Most of the genotypes have the characteristics of an episperm which can be easily removed, a seed coat which fails to penetrate the inner kernel or penetrates minimally, and a single embryo. Genotypes with these characteristics will be studied furthermore for creating new chestnut plantations in Calabria.

Summary This study, as a preliminary step toward the definition of a carbon budget model for pistachio trees (Pistacia vera L.), aimed at estimating and evaluating the dynamics of respiration of vegetative and reproductive organs of pistachio tree. Trials were performed in 2005 in a commercial orchard located in Sicily (370 m a.s.l.) on five bearing 20-year-old pistachio trees of cv. Bianca grafted onto Pistachio terebinthus L. Growth analyses and respiration measurements were done on vegetative (leaf) and reproductive (infructescence) organs during the entire growing season (April–September) at biweekly intervals. Results suggested that the respiration rates of pistachio reproductive and vegetative organs were related to their developmental stage. Both for leaf and for infructescence, the highest values were observed during the earlier stages of growth corresponding to the phases of most intense organ growth. The sensitivity of respiration activity to temperature changes, measured by Q10, showed an increase throughout the transition from immature to mature leaves, as well as during fruit development. The data collected were also used to estimate the seasonal carbon loss by respiration activity for a single leaf and a single infructescence. The amount of carbon lost by respiration was affected by short-term temperature patterns, organ developmental stage and tissue function.

The genus Pistacia is a dioecious species staminate and pistillate inflorescences born on different trees and are wind pollinated. In pistachio orchards, female and male flowering periods are often not synchronized. In fact, male trees spread their pollen before the flowers of female trees become receptive. Pollination is commonly devoted to spontaneous males of P. terebinthus. In this research authors refer to the results obtained observing the phenology of the blooming period of monoicous genotypes of P. terebinthus discovered in the Rhodope Mountains (Bulgaria). In some selected trees phenological stages have been observed in situ. The blooming date is influenced by local environmental conditions and the relative data have been correlated with the seasonal temperature time course. The male inflorescences selected had a flowering period that overlaps the female inflorescences in the third decade of April. During male and female inflorescences development of P. terebinthus trees, buds samples were collected to describe microscopic changes during sporogenesis of pistachio inflorescence.

In this study 20 accessions of loquat (Eriobotrya japonica Lindl.) that originated from Sicily and other countries were characterized phenotypically and genotyped using seven microsatellite markers. The microsatellites clearly distinguished 14 accessions; three pairs of local accessions were not differentiated, and three accessions from abroad can be considered bud sport mutations of the main Spanish cultivar ‘Algerie’. The mean alleles per locus was four, ranging from two with the marker EJ075 and five with EJ012 and EJ271; the mean Polymorphic Information Content was 0.53; the average expected and observed heterozygosities resulted 0.62 and 0.59, respectively. These values revealed a low level of genetic diversity and high relatedness among the accessions studied. The UPGMA dendrogram based on genetic distances grouped the accessions according to their geographic origin and pedigree.

Olive (Olea europaea L.) shows alternate bearing, with unreliable cropping patterns and inconsistent fruit size and quality every year. In many countries, thinning with naphthaleneacetic acid (NAA) is used to minimise alternate bearing behavior in olives. However, in Italy, growers are reluctant to employ this practice and no detailed knowledge is available for specific cultivars. We evaluated the effects of spraying NAA on various dates on the productive and vegetative characteristics of the main Italian table olive cultivar'Nocellara del Belice'. Trunk cross-sectional area, fruit set, fruit drop, fruit size, pit size, yield per tree, crop density and flesh to pit ratio were analysed. The NAA treatment applied on the earliest of the dates selected increased fruit weight and flesh to pit ratio, by reducing crop density and enhancing the leaf to fruit ratio, without reducing yield. Two distinct negative relationships were found between fruit weight and crop density during "on" and "off" years, but a unique relationship between pit weight vs. crop density in both years, suggested that the pit is the strongest sink. Fruit size and quality of'Nocellara del Belice' can be enhanced by NAA application, thereby increasing economic returns in the "on" year.

Hazelnut (Corylus avellana L.) is a traditional nut crop in southern Europe. Germplasm exploration conducted on-farm in five countries (Portugal, Spain, Italy, Slovenia, and Greece) identified 77 landraces. The present work describes phenotypic variation in nut and husk traits and investigates genetic relationships using ten simple sequence repeat (SSR) markers among these landraces, 57 well-known references cultivars, and 19 wild accessions. Among the 77 landraces, 42 had unique fingerprints while 35 showed a SSR profile identical to a known cultivar. Among the 42 unique landraces, morphological observations revealed high phenotypic diversity, and some had characteristics appreciated by the market such as nut round and caliber. Analysis of genetic relationships and population structure allowed investigation of the origin and spread of the cultivated germplasm in southern Europe. Our results indicate the existence of three primary centers of diversity in the Mediterranean basin: northwestern Spain (Tarragona) and southern Italy (Campania) in the West and Black Sea (Turkey) in the East. Moreover, the data suggest the existence of secondary gene pools in the Iberian (Asturias) and Italian (Liguria and Latium) Peninsulas, where local varieties were recently domesticated from wild forms and/or from introduced ancient domesticated varieties.

In Sicily, the chestnut (Castanea sativa Mill.) grows in limited areas of the South eastern Mt. Etna volcano and of the Northern Mountains, namely Madonie and Nebrodi. In the Island, chestnut can be considered as a neglected species, because of the modest importance recognized to it for horticultural and forestry exploitation. Recently, the Sicilian regional government founded the 'Horticultural Forestry' project to promote the cultivation of chestnut as possible fruit tree for local city farmer markets, where typical products are usually sold. The project was developed in five steps, carried out during three years by the Dipartimento di Colture Arboree of Palermo University: identification of the main growing areas; selection, during the ripening season, of the most vigorous and highly productive trees observed in each area; selection of the best genotypes, among the accessions collected, on the basis of the carpological traits, choosing the ones that presented the best fruits. The morphological characterization of husks and fruits was done referring to the UPOV descriptors list. Only 47 accessions, among hundreds of accessions observed, were chosen on the basis of the carpological traits and were studied in situ. Husk and fruit traits were recorded in the laboratory and analysed statistically, leading to a further selection of only 25 'superior' accessions. These genotypes were analysed at the molecular level using six microsatellite or SSR (Simple Sequence Repeat) primer pairs (ENICs: 4, 15, 32 and 38, CsCat: 4 and 6). SSR markers enabled the discrimination of 23 genotypes and showed low genetic distance among them. Further observations, carried out on both tree and fruit traits, led to the selection of Il 'superior' genotypes, having important carpological traits (big fruit size, absence of adherence of the seed coat to the kernel; absence of penetration of the seed coat into the embryo; mono embryonic fruit, etc.). This study could be a good start to compare autochthonous genotypes to weli know international cultivars, under the prevailing environmental conditions of the main Sicilian growing areas.