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The long-lived and evergreen olive tree dominates the Mediterranean landscape, representing an agroecological and cultural symbol and a genetic heritage of inestimable value. Sicily, for historical, geographical, and cultural reasons, has a very rich and distinctive olive germplasm. In this work, a large survey was conducted to discover, collect, and characterize the genetic diversity of centennial monumental olive trees from historical sites, such as the Greek Temple Valley (Agrigento), ancient gardens, or farmland present in the western part of the island. Trees were chosen based on their height, trunk, stump size, and presumed age; particularly, only olive trees with an age estimated at more than 400 years old were taken into consideration. For the morphological characterization, the leaf, fruit, and endocarp traits were analyzed. For the molecular characterization, 11 polymorphic microsatellite markers largely used for fingerprinting analysis were used. Reference cultivars were included in the analysis for comparison. Nuclear DNA was extracted from different parts of the plant (young leaves of shoots taken from the canopy and young leaves taken from suckers, which arose from the basal part of the tree) to check if the trees were grafted and to explore their diversity. Most of the monumental trees have been grafted at least one time during their long life, and some genotypes showed unique genetic profiles combined with peculiar phenotypic traits. Suckers (rootstock of the trees) showed a strict genetic relationship with an ancient monumental oleaster tree, also included in the study. “Patriarch” (original mother plants) trees of local cultivars were also identified. This research revealed a high level of the still unexplored genetic diversity of the Sicilian olive germplasm and highlighted its importance as a gene reservoir, which could support new breeding programs for the evaluation and possible selection of traits linked to putative resilience to abiotic and biotic stresses (particularly Xylella fastidiosa subsp. pauca ST53 or soil- borne diseases or insects). The results will be useful for improving the conservation process, enriching existing collections of olive genetic resources, and supporting on-farm conservation projects.

It is well known that autophagy is a major intracellular pathway for the degradation and recycling of cytosolic components, in both basal and stress conditions. We have recently demonstrated the activation of autophagy in P. lividus embryos: at high levels, after a stress induced by cadmium, and at basal levels, during the physiological development (1) (2). Here we report ours recent data about autophagy during oogenesis and segmentation. In order to detect autophagolysosomes (AVOs) and autolysosomes, we respectively performed incubation in vivo with acridine orange (AO), and in situ immunofluorescence (IF) with the anti-LC3 antibody (autophagy marker). All observations were carried out by Confocal Laser Scanning Microscopy. In this way we studied the trend of autophagy during oocytes maturation, after fertilization and during early developmental stages and results showed that, in all cases, the autophagic markers have specific and peculiar localizations. Furthermore we observed that the treatment with bafilomycin A1 (an inhibitor of autophagy) for 2 hours, after fertilization, generates developmental delays and morphologic anomalies, especially visible after 24 hours of development, demonstrating that autophagy is essential during the early developmental stages. This data showed the occurrence of autophagy in oocytes and during segmentation, in the first case probably for the recycling of cellular components that accumulate during oogenesis and for the elimination of the germinal vesicle, in the second case, perhaps for the removal of cellular components, between one cleavage and the following. (1) CHIARELLI R. et al. (2011) Sea urchin embryos as a model system for studying autophagy induced by cadmium stress. Autophagy. 7(9): 1028-34. (2) KLIONSKY D. et al. (2012) Guidelines for the use and interpretation of assays for monitoring autophagy (Review). Autophagy. 8(4): 1–100.

A new criterion for fatigue crack growth, whose accuracy was previously tested in the literature with the Finite Element Method, is here adopted with a Dual Boundary Element formulation. The fatigue crack growth of an elliptical inclined crack, embedded in a three dimensional cylindrical bar, is analyzed. In this way in addition to the propagation angle estimated by the Sih’s criterion, it is possible to take into account a twist propagation angle. The two propagation criteria are compared in terms of shape of the propagated crack and in terms of SIFs along the crack front. The efficiency of the Dual Boundary Element Method in this study is highlighted.