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ecosystem functions in the invaded regions, (iii) predict the ability of this species to invade European and transoceanic coastal waters, (iv) identify knowledge gaps that should be addressed to better understand the biology and ecology of this species both in its native and non-native habitats, which would improve our ability to predict H. stipulacea's potential to expand into new areas in the future. Considering the predicted climate change scenarios and exponential human pressures on coastal areas, we stress the need for coordinated global monitoring and mapping efforts that will record changes in H. stipulacea and its associated communities over time, across its native, invasive and prospective distributional ranges. This will require the involvement of biologists, ecologists, economists, modelers, managers, and local stakeholders.

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Artemia spp. is an historically popular biological model still requiring an official internationally based standardization. Several endpoints are currently available. Short-term acute endpoints include biomarker (acetylcholinesterase; heat stress proteins; lipid peroxidation; thiobarbituric acid reactive substances; thioredoxin reductase; glutathione-peroxidase; glutathione S-transferase; glutathione reductase; aldehyde dehydrogenase; and adenylpyrophosphatase and Fluotox), hatching (dry biomass, morphological disorders and size), behavioral (swimming speed and path length), teratogenicity (growth), and immobilization (meaning mortality after 5-30 s observation). Long-term chronic tests focus on growth, reproduction and survival or mortality after 7-28 d exposure from larval to adulthood stage. We analyzed each test looking at its endpoint, toxicant and experimental design including replicates, exposure time, number of exposed cysts or organisms and their relative life stage, exposure conditions during hatching and testing (salinity, pH, light intensity, aeration dilution media, and food supply), type of testing chambers, and quality assurance and quality control criteria. Similarities and differences between the identified approaches were highlighted. Results evidenced that hatching 24 h short-term and 14 d longterm mortality are the most promising Artemia spp. protocols that should go forward with international standardization.

Halophila stipulacea is a small tropical seagrass species. It is the dominant seagrass species in the Gulf of Aqaba (GoA; northern Red Sea), where it grows in both shallow and deep environments (1–50 m depth). Native to the Red Sea, Persian Gulf, and Indian Ocean, this species has invaded the Mediterranean and has recently established itself in the Caribbean Sea. Due to its invasive nature, there is growing interest to understand this species’ capacity to adapt to new conditions, which might be attributed to its ability to thrive in a broad range of ecological niches. In this study, a multidisciplinary approach was used to depict variations in morphology, biochemistry (pigment and phenol content) and epiphytic bacterial communities along a depth gradient (4–28 m) in the GoA. Along this gradient, H. stipulacea increased leaf area and pigment contents (Chlorophyll a and b, total Carotenoids), while total phenol contents were mostly uniform. H. stipulacea displayed a well conserved core bacteriome, as assessed by 454-pyrosequencing of 16S rRNA gene reads amplified from metagenomic DNA. The core bacteriome aboveground (leaves) and belowground (roots and rhizomes), was composed of more than 100 Operational Taxonomic Units (OTUs) representing 63 and 52% of the total community in each plant compartment, respectively, with a high incidence of the classes Alphaproteobacteria, Gammaproteobacteria, and Deltaproteobacteria across all depths. Above and belowground communities were different and showed higher within-depth variability at the intermediate depths (9 and 18 m) than at the edges. Plant parts showed a clear influence in shaping the communities while depth showed a greater influence on the belowground communities. Overall, results highlighted a different ecological status of H. stipulacea at the edges of the gradient (4–28 m), where plants showed not only marked differences in morphology and biochemistry, but also the most distinct associated bacterial consortium. We demonstrated the pivotal role of morphology, biochemistry (pigment and phenol content), and epiphytic bacterial communities in helping plants to cope with environmental and ecological variations. The plant/holobiont capability to persist and adapt to environmental changes probably has an important role in its ecological resilience and invasiveness.

Ancient parchments are commonly attacked by microbes, producing purple spots and detachment of the superficial layer. Neither standard cultivation nor molecular methods (DGGE) solved the issue: causative agents and colonization model are still unknown. To identify the putative causal agents, we describe the 16 S rRNA gene analysis (454-pyrosequencing) of the microbial communities colonizing a damaged parchment roll dated 1244 A.D. (A.A. Arm. I-XVIII 3328, Vatican Secret Archives). The taxa in damaged or undamaged areas of the same document were different. In the purple spots, marine halotolerant Gammaproteobacteria, mainly Vibrio, were found; these microorganisms are rare or absent in the undamaged areas. Ubiquitous and environmental microorganisms were observed in samples from both damaged and undamaged areas. Pseudonocardiales were the most common, representing the main colonizers of undamaged areas. We hypothesize a successional model of biodeterioration, based on metagenomic data and spectroscopic analysis of pigments, which help to relate the damage to a microbial agent. Furthermore, a new method (Light Transmitted Analysis) was utilized to evaluate the kind and entity of the damage to native collagen. These data give a significant advance to the knowledge in the field and open new perspectives to remediation activity on a huge amount of ancient document.

The phytopathogen Pseudomonas syringae pv. actinidiae (Psa) is the causal agent of bacterial canker of kiwifruit. In the last years, it has caused severe economic losses to Actinidia spp. cultivations, mainly in Italy and New Zealand. Conventional strategies adopted did not provide adequate control of infection. Phage therapy may be a realistic and safe answer to the urgent need for novel antibacterial agents aiming to control this bacterial pathogen. In this study, we described the isolation and characterization of two bacteriophages able to specifically infect Psa. fPSA1, a member of the Siphoviridae family, is a temperate phage with a narrow host range, a long latency, and a burst size of 178; fPSA2 is a lytic phage of Podoviridae family with a broader host range, a short latency, a burst size of 92 and a higher bactericidal activity as determined by the TOD value. The genomic sequence of fPSA1 has a length of 51,090 bp and a low sequence homology with the other siphophages, whereas fPSA2 has a length of 40 472 bp with a 98% homology with Pseudomonas putida bacteriophage gh-1. Of the two phages examined, fPSA2 may be considered as a candidate for phage therapy of kiwifruit disease, while fPSA1 seems specific toward the recent outbreak's isolates and could be useful for Psa typing.Abbreviations: PSA -Pseudomonas syringae pv. actinidiae; MOI -multiplicity of infection; PFU -plaque forming unit; TE -tris-EDTA; CFU -colony forming unit; TOD -time of death; OD 600 -at 600 nm wavelength Introduction Pseudomonas syringae pv. actinidiae (Psa), the causal agent of bacterial canker of kiwifruit, is currently damaging both Actinidia deliciosa and A. chinensis worldwide with severe economic losses [1]. On these crops, a pandemic population of the pathogen, most probably originated in China [2,3], incites different kinds of symptoms such as leaf spotting, twig wilting, flower necrosis, reddening of the lenticels, cankers along the leader and trunk as well as exudates oozing out from the canker. This Psa population differs from the one that caused relevant damages to the green-fleshed kiwifruit (i.e., A. deliciosa) in Japan and South Korea in the 1980-1990 period [4-7]. Control measures aiming to reduce the incidence, severity, and spreading of the disease, have been undertaken in all areas of cultivation. A common practice applied everywhere is the cutting and the subsequent destruction of the infected plants or plant parts to reduce the inoculum pressure of the pathogen. Different control strategies have followed in different countries. In New Correspondence: Gustavo Di Lallo, Dipartimento di Biologia, Universita' di Roma "Tor Vergata", I-00133, Rome, Italy E-mail: dilallo@uniroma2.it Phone: þ39 6 72594243 Fax: þ39 6 2023500 Environment Health TechniquesBacteriophages infecting P. syringae pv. actinidiae 1 ß