298 research outputs found

    Phloem cytochemical modification and gene expression following the recovery of apple plants from apple proliferation

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    Recovery of apple trees from apple proliferation was studied by combining ultrastructural, cytochemical, and gene expression analyses to possibly reveal changes linked to recovery-associated resistance. When compared with either healthy or visibly diseased plants, recovered apple trees showed abnormal callose and phloem-protein accumulation in their leaf phloem. Although cytochemical localization detected Ca2+ ions in the phloem of all the three plant groups, Ca2+ concentration was remarkably higher in the phloem cytosol of recovered trees. The expression patterns of five genes encoding callose synthase and of four genes encoding phloem proteins were analyzed by quantitative real-time reverse transcription- polymerase chain reaction. In comparison to both healthy and diseased plants, four of the above nine genes were remarkably upregulated in recovered trees. As in infected apple trees, phytoplasma disappear from the crown during winter, but persist in the roots, and it is suggested that callose synthesis/deposition and phloem-protein plugging of the sieve tubes would form physical barriers preventing the recolonization of the crown during the following spring. Since callose deposition and phloem-protein aggregation are both Ca2+-dependent processes, the present results suggest that an inward flux of Ca2+ across the phloem plasma membrane could act as a signal for activating defense reactions leading to recovery in phytoplasma-infected apple trees.L'articolo é disponibile sul sito dell'editore: http://www.apsjournals.apsnet.or

    My Health Diary, a School-Based Well-Being Program: A Randomized Controlled Study.

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    Background: A positive transition to adulthood entails developing the individual and social skills needed to cope with critical situations. The “My Health Diary” program was designed as a school-based and teacher-led intervention focusing on the active engagement of 12- to 13-year-old pre-adolescents. The study analyzes the role of several primary variables (psychological well-being, psychosomatic symptoms, health status), secondary variables (health-risk behaviors, prosocial behavior, academic success, physical and verbal aggression), and mediator variables of emotional and social skills in terms of empathic and social self-efficacy, and satisfaction with school. Methods: Sixty schools were involved, divided into control groups (N = 29) and intervention groups (N = 31). The program was administered only to the intervention group. Of the 2306 students at the baseline, 2078 were still involved at post-intervention 6 months later. Results: The program was not found to have significant effects on the primary outcome variables and most of the secondary variables. For the mediators, however, the association was stronger for the girls in the intervention group, and there was a statistically significant difference in the empathic skills shown by girls, who reported higher levels than boys. Conclusions: The program was found to have encouraging effects on some mediators and in enhancing socio-relational and emotional skills among pre-adolescents

    Molecular characterization of ‘Candidatus Phytoplasma prunorum’ in Cacopsilla pruni insect vector

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    Recent investigations on molecular characterization of the ‘Candidatus Phytoplasma prunorum’ (16SrX-B subgroup), causal agent of the European Stone Fruit Yellows (ESFY) syndrome, on the non ribosomal tuf gene resulted in the finding of two groups of isolates, named ‘type a’ and ‘type b’, both with a distinctive geographical distribution in Italian stone fruit growing areas (Ferretti et al., 2007 and 2008). Considering the role of Cacopsylla pruni (Scopoli) in the epidemiological cycle of the disease, the presence of the two groups of isolates has also been investigated in infected psyllid individuals from different Italian areas. Both types have been identified in C. pruni specimens collected on apricot, plum and wild Prunus species, confirming the geographical distribution and the percentages of spread of the two isolates

    Molecular characterization of ‘Candidatus Phytoplasma prunorum’ in Cacopsilla pruni insect vector

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    Recent investigations on molecular characterization of the ‘Candidatus Phytoplasma prunorum’ (16SrX-B subgroup), causal agent of the European Stone Fruit Yellows (ESFY) syndrome, on the non ribosomal tuf gene resulted in the finding of two groups of isolates, named ‘type a’ and ‘type b’, both with a distinctive geographical distribution in Italian stone fruit growing areas (Ferretti et al., 2007 and 2008). Considering the role of Cacopsylla pruni (Scopoli) in the epidemiological cycle of the disease, the presence of the two groups of isolates has also been investigated in infected psyllid individuals from different Italian areas. Both types have been identified in C. pruni specimens collected on apricot, plum and wild Prunus species, confirming the geographical distribution and the percentages of spread of the two isolates.Keywords: ESFY, phytoplasma, characterization, tuf gene, insect vecto

    Prediction of the kiwifruit decline syndrome in diseased orchards by remote sensing

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    Eight years after the first record in Italy, Kiwifruit Decline (KD), a destructive disease causing root rot, has already affected more than 25% of the area under kiwifruit cultivation in Italy. Diseased plants are characterised by severe decay of the fine roots and sudden wilting of the canopy, which is only visible after the season's first period of heat (July-August). The swiftness of symptom appearance prevents correct timing and positioning for sampling of the disease, and is therefore a barrier to aetiological studies. The aim of this study is to test the feasibility of thermal and multispectral imaging for the detection of KD using an unsupervised classifier. Thus, RGB, multispectral and thermal data from a kiwifruit orchard, with healthy and diseased plants, were acquired simultaneously during two consecutive growing seasons (2017-2018) using an Unmanned Aerial Vehicle (UAV) platform. Data reduction was applied to the clipped areas of the multispectral and thermal data from the 2017 survey. Reduced data were then classified with two unsupervised algorithms, a K-means and a hierarchical method. The plant vigour (canopy size and presence/absence of wilted leaves) and the health shifts exhibited by asymptomatic plants between 2017 and 2018 were evaluated from RGB data via expert assessment and used as the ground truth for cluster interpretation. Multispectral data showed a high correlation with plant vigour, while temperature data demonstrated a good potential use in predicting health shifts, especially in highly vigorous plants that were asymptomatic in 2017 and became symptomatic in 2018. The accuracy of plant vigour assessment was above 73% when using multispectral data, while clustering of the temperature data allowed the prediction of disease outbreak one year in advance, with an accuracy of 71%. Based on our results, the unsupervised clustering of remote sensing data could be a reliable tool for the identification of sampling areas, and can greatly improve aetiological studies of this new disease in kiwifruit

    Hypo- and hyper-virulence in apricot trees infected by European stone fruit yellows

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    An apricot orchard, located in an area of north eastern Italy under serious pressure from European stone fruit yellows (ESFY) infection, has been monitored since the year it was planted (1990). During this time, most of the trees displayed symptoms or were shown by PCR analyses to be infected. Two groups of apricot trees were particularly interesting: some trees were asymptomatically infected while others recovered from the symptoms but not from the pathogen. In order to isolate those strains of the phytoplasma characterised by varying virulence, each of the two groups was used as mother plants and propagated. The new trees were used to constitute experimental orchards, where they were observed for the presence of symptoms and in part were tested by PCR, starting in 2003. The results obtained confirmed the presence of strains of the pathogen characterised by varying virulence. The strains originally present in infected apricot trees which recovered from the symptoms of ESFY were seen to be hypovirulent; none of the propagated infected trees ever showed symptoms of the disease. Surprisingly, the strains present in asymptomatic apricot mother plants were hypervirulent and the propagated trees always displayed severe symptoms. In the propagated trees, the transmission of the pathogen was higher in the hypervirulent strains than in the hypovirulent ones. A graft transmission trial carried out in the greenhouse using some of the identified hypo- and hypervirulent strains, confirmed the results obtained in open field. Real time PCR analyses showed that in the trees infected by hypovirulent strains the colonisation of the pathogen was lower than in those infected by the hypervirulent strains. It is possible to affirm that the hypovirulent strains were present in those mother plants which had originally recovered. The research will continue with the aim of verifying the possibility of cross protection among the identified hypo- and hypervirulent strains.Keywords: ‘Candidatus Phytoplasma prunorum’, real-time PCR, Prunu

    Hypo- and hyper-virulence in apricot trees infected by European stone fruit yellows

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    An apricot orchard, located in an area of north eastern Italy under serious pressure from European stone fruit yellows (ESFY) infection, has been monitored since the year it was planted (1990). During this time, most of the trees displayed symptoms or were shown by PCR analyses to be infected. Two groups of apricot trees were particularly interesting: some trees were asymptomatically infected while others recovered from the symptoms but not from the pathogen. In order to isolate those strains of the phytoplasma characterised by varying virulence, each of the two groups was used as mother plants and propagated. The new trees were used to constitute experimental orchards, where they were observed for the presence of symptoms and in part were tested by PCR, starting in 2003. The results obtained confirmed the presence of strains of the pathogen characterised by varying virulence. The strains originally present in infected apricot trees which recovered from the symptoms of ESFY were seen to be hypovirulent; none of the propagated infected trees ever showed symptoms of the disease. Surprisingly, the strains present in asymptomatic apricot mother plants were hypervirulent and the propagated trees always displayed severe symptoms. In the propagated trees, the transmission of the pathogen was higher in the hypervirulent strains than in the hypovirulent ones. A graft transmission trial carried out in the greenhouse using some of the identified hypo- and hypervirulent strains, confirmed the results obtained in open field. Real time PCR analyses showed that in the trees infected by hypovirulent strains the colonisation of the pathogen was lower than in those infected by the hypervirulent strains. It is possible to affirm that the hypovirulent strains were present in those mother plants which had originally recovered. The research will continue with the aim of verifying the possibility of cross protection among the identified hypo- and hypervirulent strains

    A Cloud Based Service for Management and Planning of Autonomous UAV Missions in Smart City Scenarios

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    Cloud Robotics is an emerging paradigm in which robots, seen as abstract agents, have the possibility to connect to a common network and share on a complex infrastructure the information and knowledge they gather about the physical world; or conversely consume the data collected by other agents or made available on accessible database and repositories. In this paper we propose an implementation of an emergency-management service exploiting the possibilities offered by cloud robotics in a smart city scenario. A high-level cloud-platform manages a number of unmanned aerial vehicles (quadrotor UAVs) with the goal of providing aerial support to citizens that require it via a dedicated mobile app. The UAV reaches the citizen while forwarding a realtime video streaming to a privileged user (police officer),connected to the same cloud platform, that is allowed to teleoperate it by remote

    Rare and Insidious Toxicities from New Combination Therapies in Metastatic Renal Cell Cancer: Lessons Learned from Real-Practice

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    The advent of immune checkpoint inhibitors in combination with multitarget tyrosine kinase inhibitors has become a standard first-line treatment for metastatic renal cell cancer. Along with survival improvement, new toxicities have emerged. Such adverse events are still complex to be managed and some of them are rare and could be insidious or even fatal. Medical oncologists dispose of guidelines about the management of toxicities from immune checkpoint inhibitors but not for combinations. Therefore, it is still difficult to properly attribute and manage additive or overlapping adverse events. We report two clinical cases regarding rare treatment-related endocrine toxicities—hypophysitis and thyroiditis—with particular focus on their management. To this purpose, immune checkpoint-related toxicities guidelines represent the starting point. However, their implementation with additional measures is needed, considering the increasing complexity of current clinical scenarios. The goal is to correctly recognize adverse events and address side effects, so as not to discontinue effective treatments. We, therefore, aim at discussing the points of proper management of toxicities and individuating potential areas of improvement

    Investigating Genomic Variability and Molecular Mechanisms of Pathogenesis in ‘Candidatus Phytoplasma solani’

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    ‘Candidatus Phytoplasma solani’ (CaPsol) is a phloem-limited bacterium associated in Europe and the Mediterranean basin with bois noir (BN) disease of grapevine and with stolbur diseases of tomatoes, potatoes and other solanaceous crops. Its ecology is highly intricate, involving various insect vectors, primarily the planthopper Hyalesthes obsoletus, and a diverse range of host plants within agroecosystems. Developing effective control measures requires understanding the complex interactions between the phytoplasma and its hosts. CaPsol pathogenicity relies on effector proteins that disrupt plant hormone signaling, cell cycle regulation, and immune defenses, facilitating colonization, spread, and symptom development. The main aim of this work is to (i) type CaPsol strains from BN-affected grapevines by multiple gene (tufB, stamp, vmp1) sequence analyses and to investigate differences in their virulence studying their prevalence in grapevines exhibiting a range of symptom severity; and (ii) identify genes encoding for phytoplasma secreted effectors from the genomes of nine genetically distinct CaPsol strains to evaluate their expression variations in grapevine. CaPsol genome analysis was performed to identify protein-coding sequences (CDS) using PRODIGAL. Putative effector prediction was done using SignalP and TargetP, focusing on cleavage sites and signal peptides via neural networks and Markov models. InterProScan classified proteins into families and identified functional domains. Molecular typing results showed a high variability and diversity of CaPsol strains infecting grapevines showing severe and mild symptoms. Genome analysis identified 30 effectors, categorized by localization within or outside sequence variable mosaic (SVM) regions. Primers for qPCR were designed to evaluate effector gene expression in grapevine. Findings would improve our understanding of CaPsol-plant interactions, aiding sustainable control strategies
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