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Salix acmophylla Boiss. has a traditional role in several regions of the Middle East and the Indian subcontinent. As with many other woody species, the development of methods for fast propagation and ex situ conservation of this species is needed. We describe for the first time a micropropagation protocol of three S. acmophylla ecotypes. The best results for shoot proliferation were obtained by culturing the shoot explants on Woody Plant Medium (WPM) containing benzyladenine (BA) 5 μM, but it was also observed that proliferation can be further enhanced by the separation of the shoot tip from the underlying internodes, followed by their respective culture on BA- or activated-charcoal-containing medium. Thidiazuron or zeatin did not enhance shoot proliferation. The rooting of shoots occurred spontaneously, but for the ecotype with a lower propensity for rooting, treatment with 5 μM indolebutyric acid (IBA) increased rooting percentage. Genetic differences were evident in rooting success, but not in shoot development of the tested ecotypes in response to in vitro cultural conditions.

L'uso del carbone attivo è piuttosto diffuso nella coltura in vitro (Pan e Van Staden, 1998; Thomas, 2008); il suo impiego, infatti, è associato al miglioramento dei risultati in alcune fasi di crescita di diverse tecniche, quali micropropagazione ed embriogenesi somatica, rivelandosi di particolare utilità per numerose specie, soprattutto arboree (Bon et al., 1988; Mohamed-Yasseen, 1994; Dumas e Monteuuis, 1995; Capuana e Debergh, 1997; Andrade e Merkle, 2005; Sul e Korban, 2005; Zouine et al., 2005; Sosa-Rodriguez et al., 2014). Recentemente è stato proposto, come alternativa all'uso del carbone attivo, il biochar, prodotto ottenuto da un processo di rapida pirolisi di sostanze organiche, comprendenti anche residui di origine agricola o forestale. Il suo impiego è stato finora sperimentato quasi esclusivamente in pieno campo, con risultati di notevole interesse (Yamato et al., 2006; Chan et al., 2007; Blackwell et al., 2009; Baronti et al., 2010; Gaskin et al., 2010). Sono stati perciò avviati alcuni studi per verificare le possibilità di un suo utilizzo nella coltura in vitro (Di Lonardo et al., 2013). Si tratta di indagini preliminari in un ambito alquanto ristretto, per cui non possono ancora essere fornite indicazioni definitive circa la sua efficacia e/o convenienza; le prime osservazioni disponibili, comunque, fanno ritenere la sua utilizzazione un'alternativa possibile e promettente per diversi aspetti.

Embryogenic cultures of horse chestnut (Aesculus hippocastanum L.) can be obtained from different organs and tissues. We describe here the induction from stamen filaments and the procedures applied for the successive phases of somatic embryo development and maturation. Embryogenic tissues are obtained on Murashige and Skoog medium containing 9.0 µM 2,4-dichlorophenoxyacetic acid. Somatic embryos develop after transfer to hormone-free medium enriched with glutamine. Maturation and germination of isolated embryos are achieved by transfer to medium containing polyethylene glycol 4000 and activated charcoal, successive desiccation treatment and cold storage at 4°C for 8 weeks.

Redwood (Sequoia sempervirens (D. Don.) Endl.) is an evergreen conifer tree of the Sequoia genus. The reddish-brown lumber of the tree is highly valued, not only for its beauty, but also for its light weight, resistance and wood quality, making the tree the most attractive species for timber and plywood production. Present study aimed to develop medium- and long-term conservation approaches for redwood germplasm. For medium-term conservation, in vitro shoot cultures were maintained at 4°C, in darkness, up to 15 months ('slow growth storage'). Study evaluated the effects of different medium compositions on survival and regrowth of the material following the storage at low temperature. Outcomings of the study demonstrated that cold storage could be prolonged to 12 months on QL-based media without any significant decrease in the survival and regrowth potential of the cultures. Elongated and etiolated shoots, obtained after storage, were highly vigorous and multiplication could be re-initiated easily. MS-based media, however, were less effective, permitting 9 months of storage when the medium was hormonefree. As for long-term conservation, following cold hardening of in vitro shoot cultures and sucrose preculturing of excised buds, cryopreservation was performed by using droplet vitrification method. Post-thaw recovery was possible for a large range of PVS2 exposure, 135 min treatment providing 18 and 22% recovery of apical and basal buds, respectively.

Sono riportati i risultati di una ricerca sulla conservazione a medio termine di Castanea sativa coltivato in vitro e conservato alle temperature di 4° e 8° C.

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An efficient cryopreservation protocol for the safe storage of Fraxinus excelsior L. embryogenic callus cultures is reported. The cryopreservation methods tested included one-step freezing by means of (i) encapsulation-vitrification; or (ii) encapsulation-dehydration; and (iii) slow cooling using the Nalgene Freezing container, Mr Frosty (R), which produces a temperature decrease of about 1 degrees C min(-1) when placed in a -70 degrees C freezer. None of the one-step freezing techniques was effective for cryopreservation of encapsulated callus masses, irrespective of the cryoprotective treatment applied, i.e., treatment with the PVS2 vitrification solution or physical dehydration with silica gel before direct immersion in liquid nitrogen. On the contrary, when a slow cooling protocol was applied to embryogenic callus which had been pretreated for 60 min with a 210 g l(-1) (0.61 M) sucrose-7.5% DMSO cryoprotective solution, up to about 1.3 g per Petri dish of proliferating callus was observed 42 days after recovery from liquid nitrogen, and cultures were able to produce somatic embryos 8 weeks after transfer to semi-solid medium. TTC staining of callus cultures provided a fast evaluation of culture viability.

The work was focused on the in vitro screening for the selection of Populus alba clones for phytoremediation purposes. Tolerance, accumulation and translocation of some heavy metals were investigated in three poplar clones .

The application of three different vitrification-based freezing strategies for the cryostorage of white poplar (Populus alba L.) and hybrid aspen (P. tremula L. x P. tremuloides Michx.) have been assessed. The PVS2 vitrification protocol was Successfully applied to two white poplar in vitro clones stored for more than 6 months in slow-growth conditions (4 degrees C, in darkness) and showing clear signs of explant etiolation and decay. After 60 min of PVS2 treatment, P. alba L. (cv. Villafranca) explants isolated from axillary buds demonstrated significantly better potential for post-freeze regrowth (64%) compared to those obtained from apical buds (17%). Similarly, a high level of survival (78%) of the frozen hybrid aspen shoot tips was recorded following the application of the same technique. Using the 'encapsulation-vitrification' procedure, no toxic effects of the PVS2 treatment were noticed after 120 min exposure, however none of the cryopreserved (poplar and aspen) explants survived after 3 weeks. In contrast, the 'droplet-vitrification' technique appeared to be very efficient in the cryopreservation of white poplar shoot tips, which increases the opportunities for wider application of this method in other woody species.

In vitro rooting of Populus alba after treatment with different concentrations of some heavy metals.

Clonal propagation of myrtle can be successfully achieved by micropropagation and, for many reasons related also to this, it would be of interest to make a method available for medium-term conservation of in vitro cultures. In our work we investigated the effect of low-temperature storage on the survival and proliferation capacity of microshoots. The influence of pre-treatments with abscisic acid and of conservation on mannitol-containing media were also investigated. It was found that myrtle can be easily stored for at least 6 months at 8°C, recovering its proliferation capacity after this period.

Isolation of bacteria from Fraxinus spp. seeds

An effective procedure for the cryopreservation of horse chestnut (Aesculus hippocastanum L.) embryogenic callus by vitrification/one-step freezing is described here. In particular, the study focused on the possibility of recovering the full proliferation potential of the embryogenic lines after storage in liquid nitrogen. The developmental stage of the embryogenic lines was shown to play an important role. Ninety-min. incubation in PVS2 and conservation at -196 °C of callus samples, containing a prevalence of embryogenic masses at an advanced stage of somatic embryo maturation (i.e. the torpedo stage) gave optimum regrowth of healthy and proliferating embryogenic callus. Moreover, raising the thawing temperature to 45°C yielded the maximum survival (94%) of torpedo-stage embryogenic samples, recovery of proliferation and, in more than 70% of cases, maturation to the cotyledonary stage. This study opens the way to the possibility of safe, long-term storage in liquid nitrogen of valuable embryogenic lines of horse-chestnut, avoiding repeated subculturing.

Some aspects related to the rooting of cuttings of Cupressus sempervirens were examined in this work. They are of both scientific and practical relevance, dealing with the genetic variability of the rooting ability, the expression of this character in different periods of the year and the efficiency of the modality of hormone supplying. A greater efficiency of indole-butyric acid given to the cuttings in the form of either potassium salt solution or talcum dispersion were found, compared to the alcoholic solution. The different treatments did non affect the number of adventitious roots per cutting and the mean root length. A strong variability in the rootability of cuttings was found among different genotypes. In an experiment performed on April with 20 selected clones, the rooting percentage of the K-IBA-treated cuttings ranged between 0% and 88%, with most of the clones showing a rooting potential below 30%; in the same trial the best-rooting clone gave 34% rooting of nontreated cuttings. In another experiment performed on December the rooting was very poor for all the clones tested, whether for the treated or for the untreated cuttings. With three clones characterised by a different rooting potential, the rootability of cuttings was detected, along the best rooting season, making a series of tests in which cuttings were collected at short intervals. A characteristic trend in the ability to root, in terms of natural and induced root potential and, particularly, in the expression of this potential along the period studied was observed in the clones tested.

Exogenous ethylene production was determined in common cypress (Cupressus sempervirens) shoots cultured in vitro in the presence of canker-inducing Seiridium cardinale culture filtrates. Cypress clones 322 and 318, which show resistance to cortical canker, were found to produce higher amounts of ethylene as compared with non-infected control shoots, whereas susceptible clones 394 and 819 did not differ from the control in exogenous ethylene production, suggesting that differential ethylene production could be useful in early screening of cypress genotypes resistant to canker.

A mutual impact of gastrointestinal tract (GIT) and central nervous system (CNS) functions has been recognized since the mid-twentieth century. It is accepted that the so-called gut-brain axis provides a two-way homeostatic communication, through immunological, hormonal and neuronal signals. A dysfunction of this axis has been associated with the pathogenesis of some diseases both within and outside the GIT, that have shown an increase in incidence over the last decades. Studies comparing germ-free animals and animals exposed to pathogenic bacterial infections, probiotics or antibiotics suggest the participation of the microbiota in this communication and a role in host defense, regulation of immunity and autoimmune disease appearance. The GIT could represent a vulnerable area through which pathogens influence all aspects of physiology and even induce CNS neuro-inflammation. All those concepts may suggest the modulation of the gut microbiota as an achievable strategy for innovative therapies in complex disorders. Moving from this background, the present review discusses the relationship between intestinal microbiota and CNS and the effects in health and disease. We particularly look at how the commensal gut microbiota influences systemic immune response in some neurological disorders, highlighting its impact on pain and cognition in multiple sclerosis, Guillain-Barrè Syndrome, neurodevelopmental and behavioral disorders and Alzheimer's disease. In this review we discuss recent studies showing that the potential microbiota-gut-brain dialogue is implicated in neurodegenerative diseases. Gaining a better understanding of the relationship between microbiota and CNS could provide an insight on the pathogenesis and therapeutic strategies of these disorders.

In this study, the efficiency of three vitrification-based cryopreservation techniques, i.e. vitrification, encapsulation-vitrification and droplet-vitrification were compared for cryopreserving Sequoia sempervirens apical and basal buds sampled from in vitro shoot cultures. The effect of cold-hardening of mother-plants and of bud culture medium and sucrose preculture was also investigated. Culture of apical and basal buds sampled from cold-hardened mother-plants on Quoirin and Lepoivre medium with activated charcoal had a positive effect on regrowth. Only droplet-vitrification ensured survival and regrowth after cryopreservation. After cryopreservation, regeneration of apical buds was possible for PVS2 exposure durations between 90 and 180 min but it remained low, with a maximum of 18% after 135 min treatment. With basal buds, regeneration after cryopreservation was possible over a larger range of PVS2 treatment durations, between 30 and 180 min. The highest regeneration percentage was slightly higher (22%) than that measured with apical buds, and was also achieved after 135 min PVS2 exposure.