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Rapid growth of human pressure on natural resources has led profound changes in the natural environment. Habitat destruction, fragmentation and isolation are widespread and resulting in human-dominated landscapes. Many species have suffered local extinctions due to fragmentation and loss of natural habitats, while their ability to expand and re-colonize is hampered by the low degree of connectivity between the landscape fragments. Biodiversity conservation depends, therefore, on the maintenance of functional ecological networks and on the specific capacity of adaptation in fragmented habitats. Initiatives aimed at sustainability and preservation of agro-forestry resources are needed to halt biodiversity loss and to restore habitat connectivity. Understanding the complex interactions between biological, physical and socio-cultural components that shaped the current landscape, has stimulated the development of interdisciplinary methods. They consider the landscape, and all the variables associated with it, as a fundamental element of analysis. Research in the landscape ecology field has improved understanding of both the causes and the consequences of spatial heterogeneity, and how these vary with scale, coming to an effective influence on management of both natural and human-shaped landscapes. An abundance of spatially-explicit datasets and GIS technology supply critical tools for exploring spatial variation in several ecological variables. GIS spatial analysis functions are now essential to investigate the spatial relationships among biological, physical and anthropic landscape components. In this study, we explored the possibility to combine spatial analysis techniques with analytical tools coming from different research fields, providing new insights in sustainability and conservation study of agro-forestry resources. Landscape genetics approach (Manel et al. 2003) that combine data and methods of landscape ecology and population genetics, was applied to understand the spatial genetic structure of forest species populations and the effects of the landscape composition (post-glacial expansion, environmental and physical barriers) on gene flow and genetic variability. We investigated the origin and the processes that have affected the current distribution of Castanea sativa in Europe, and Juglans regia in Asia, through the analysis of the spatial structure and genetic diversity of existing populations, in relation to landscape and environmental variables. We used the overlay technique, described by Holderegger et al. (2010), based on (1) identification of the main clusters of populations (genetic structure by Bayesian clustering), (2) detection of genetic discontinuities or barriers, and (3) interpolation of genetic variables/membership coefficient (Qi) among individuals or populations (kriging, IDW resulting in genetic isolines). The genetic clusters, genetic discontinuities, barriers, or isolines are overlaid on topographical or land cover/land use maps to search for spatial coincidences with landscape elements. Isoscapes, namely joining the terms isotopes and landscapes, are maps that represent spatial variability of isotope composition, as related to biological and biophysical processes. We explored the potential of combining stable isotope analysis techniques (IRMS) and spatial analysis to understand the spatial distribution of isotope ratio variation in rural and forest resources. Starting from a first attempt concerning the integration of isoscapes analysis in traceability studies of biological products, we present future research perspectives.

La Juglans regia (L.) è una specie arborea multi-funzionale, nota per il legno pregiato e i frutti di qualità, che cresce in Italia da 0 a 1500 m s.l.m.. Nelle aree montane e marginali ha svolto a lungo un ruolo importante per la sussistenza della famiglia rurale e per la connotazione paesaggistica e idrogeologica del territorio. In tali aree ancor'oggi esistono molte varietà locali e/o ecotipi, scarsamente conosciuti o negletti, degni di essere riscoperti e valorizzati. Il progetto FIMONT, finanziato dal MiUR, tra i cinque case studies affrontati, ha considerato il "Noce di Montagna" per suggerire informazioni, metodi e strategie che possano incrementare il valore del germoplasma montano di noce. A tal fine si è proceduto a: 1) l'individuazione di una macroarea di studio rappresentativa dei territori montani d'Italia vocati alla nocicoltura; 2) l'analisi dello stato dell'arte delle dinamiche di filiera, delle noci e della frutta secca, all'interno della macroarea di studio; 3) la messa a punto di metodologie per il controllo di provenienza del Noce di Montagna (marcatori molecolari); 4) lo sviluppo di strategie per la valorizzazione del prodotto. L'analisi degli aspetti di filiera ha evidenziato diversi punti critici. Sul mercato tradizionale le produzioni non specializzate di Noci di Montagna non sono economicamente e tecnologicamente competitive nei confronti di produzioni specializzate e internazionali. Le analisi genetiche, però, hanno evidenziato delle particolarità che sembrano collegare le popolazioni di noce, campionate nelle aree appenniniche interne, all'antichissima pratica della transumanza delle greggi. Ulteriori analisi su gruppi di noci campionati lungo il percorso del Regio Tratturo Pescasseroli-Candela sembrano rafforzare l'ipotesi. Gli spostamenti operati dall'uomo nel corso dei secoli hanno influenzato la naturale dinamica di diffusione del noce e hanno determinato, insieme ai fattori ambientali, la selezione di ecotipi genetici particolari che si distinguono nettamente dalle varietà più diffuse nel sud Italia. La ricerca ha così legato il Noce di Montagna al Regio Tratturo e alla transumanza, fornendo una caratteristica fortemente utile a connotare il prodotto Noce di Montagna. Il caso studio Noce di Montagna è un interessante esempio di come metodologie analitiche di laboratorio di tipo genetico e molecolare possano rappresentare uno strumento utile per il controllo e la caratterizzazione del prodotto. I metodi e le strategie seguite possono essere applicati con successo in altre realtà.

In this study the lacking of suitable, cheap and reliable methods for pollen storage and viability and the correspondent difficulty to produce progeny in breeding and research programs using controlled crosses in Juglans genus is presented. In particular Juglans nigra (Eastern Black walnut) and Juglans regia (common or Persian walnut) are highly economically important species in Europe, Asia and North America. Both species are monoecious, heterodichogamous and wind -pollinated. Their mating system is predominantly outcrossing, although under particular environmental conditions self-pollination is possible. Natural hybrids between the two species, Juglans x intermedia (Carr) can occur naturally. Compared to the parental species, most J. × intermedia (J. nigra × J. regia) hybrids show increased vegetative vigor, distinct disease resistance, high wood quality, and greater winter-hardiness. For these reasons there is great demand for J. × intermedia for forestry, especially in Northern Europe. One of the main problem in black, and common walnut production is that breeders have encountered difficulties obtaining sufficient quantities of desired pollen at the time pistillate flowers are receptive because of the dichogamous nature of the species. Several long-term walnut pollen storage techniques were developed but no suitable and simple method is available in Juglans until now. In addition, pistillate flower abortion (PFA), caused by excessive pollen load, has been reported in Persian and black walnut. PFA may severely affects the final nut set. Moreover for production of hybrid progeny it also requested the synchrony of flowering and genetic compatibility between parental trees. Several studies has been focused on biological mechanisms underlying the pistillate flower abortion, the low pollen viability, fertilization and embryogenesis in walnut . In the last two decades the scientists were seeking to overcome practical problems in programs for the genetic improvement of walnut, using open-pollinated progeny tests instead of controlled cross progeny tests. In particular we reported a new method for retrospective identification of hybridogenc walnut trees based on SSR fingerprinting and parentage analysis in order to establish new for seed orchards for hybrid production.

Risultati della sperimentazione impianti di robinia pseudoacacia per produzione di biomassa.