193 research outputs found

    Major and Emerging Fungal Diseases of Citrus in the Mediterranean Region

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    This chapter deals with major endemic and emerging fungal diseases of citrus as well as with exotic fungal pathogens potentially harmful for citrus industry in the Mediterranean region, with particular emphasis on diseases reported in Italy and Maghreb countries. The aim is to provide an update of both the taxonomy of the causal agents and their ecology based on a molecular approach, as a preliminary step towards developing or upgrading integrated and sustainable disease management strategies. Potential or actual problems related to the intensification of new plantings, introduction of new citrus cultivars and substitution of sour orange with other rootstocks, globalization of commerce and climate changes are discussed. Fungal pathogens causing vascular, foliar, fruit, trunk and root diseases in commercial citrus orchards are reported, including Plenodomus tracheiphilus, Colletotrichum spp., Alternaria spp., Mycosphaerellaceae, Botryosphaeriaceae, Guignardia citricarpa and lignicolous basidiomycetes. Diseases caused by Phytophthora spp. (oomycetes) are also included as these pathogens have many biological, ecological and epidemiological features in common with the true fungi (eumycetes)

    Spiroplasma spp.: A Plant, Arthropod, Animal and Human Pathogen

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    Mollicutes is a class of smallest and free-living bacteria. They have no cell wall and their plasma membrane contains cholesterol; nevertheless, cellular organization does not differ from that of other prokaryotes. They are used as simple model systems for studying general biological problems, such as those concerning membrane structure and functions, symbiosis between arthropods and microrganisms, animal and plant pathogens. Mollicutes includes the family of Spiroplamataceae, which contains Spiroplasma genus, a group of species associated, in different manner, with arthropods (insects, mites, crustaceans). Spiroplasma species can be commensals or parasites and even be involved in more close symbiosis, such as synergism or mutualism. Out of 38 described Spiroplasma species, only three have been associated with plant diseases and three with arthropod diseases. Moreover, some species have been related to animal diseases, such as transmissible spongiform encephalopathy (TSE), and their role in human disease has been assessed. The chapter describes the taxonomic situation of the genus and reports the most important diseases due to the presence of Spiroplasma in different living organisms with special emphasis on citrus in which it causes one of the most economically damaging infectious diseases in a number of citrus growing areas worldwide

    DNA Metabarcoding and Isolation by Baiting Complement Each Other in Revealing Phytophthora Diversity in Anthropized and Natural Ecosystems

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    Isolation techniques supplemented by sequencing of DNA from axenic cultures have provided a robust methodology for the study of Phytophthora communities in agricultural and natural ecosystems. Recently, metabarcoding approaches have emerged as new paradigms for the detection of Phytophthora species in environmental samples. In this study, Illumina DNA metabarcoding and a conventional leaf baiting isolation technique were compared to unravel the variability of Phytophthora communities in different environments. Overall, 39 rhizosphere soil samples from a natural, a semi-natural and a horticultural small-scale ecosystem, respectively, were processed by both baiting and metabarcoding. Using both detection techniques, 28 out of 39 samples tested positive for Phytophthora. Overall, 1,406,613 Phytophthora internal transcribed spacer 1 (ITS1) sequences and 155 Phytophthora isolates were obtained, which grouped into 21 taxa, five retrieved exclusively by baiting (P. bilorbang; P. cryptogea; P. gonapodyides; P. parvispora and P. pseudocryptogea), 12 exclusively by metabarcoding (P. asparagi; P. occultans; P. psycrophila; P. syringae; P. aleatoria/P. cactorum; P. castanetorum/P. quercina; P. iranica-like; P. unknown sp. 1; P. unknown sp. 2; P. unknown sp. 3; P. unknown sp. 4; P. unknown sp. 5) and four with both techniques (P. citrophthora, P. multivora, P. nicotianae and P. plurivora). Both techniques complemented each other in describing the variability of Phytophthora communities from natural and managed ecosystems and revealing the presence of rare or undescribed Phytophthora taxa

    First Report of Root and Basal Stem Rot Caused by Phytophthora cryptogea and P. inundata on Dwarf Banana in Italy

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    In Sicily (southern Italy) local cultivars of dwarf banana (Musa acuminata) are cultivated for edible fruit and as ornamental plants. During the summer of 2015, in an ornamental nursery of Aci San Filippo (Catania province), eastern Sicily, ten out of forty mature plants of dwarf banana grown in the field showed leaf chlorosis, wilt and sudden collapse of the entire plant associated with root and basal stem rot. Two Phytophthora species (overall 24 and 22 isolates, respectively) were consistently recovered directly from rotted roots and stems on BNPRA-HMI selective medium (Masago et al. 1977). Pure cultures of both species were obtained by single-hypha isolations. The first species formed slight petaloid colonies on potato dextrose agar (PDA) and slightly fluffy colonies on V-8 juice agar (V8A). It grew between 2 and 30°C, with an optimum of 25°C. On V8A discs flooded with non-sterile soil extract this species produced persistent, ovoid to obpyriform, non-papillate, internally proliferating sporangia (35 ..

    Phytophthora Ă— pelgrandis Causes Root and Collar Rot of Lavandula stoechas in Italy.

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    In 2007, Phytophthora isolates with atypical morphological and biological characteristics were found associated with root and collar rot of potted plants of Stoechas lavender (Lavandula stoechas) in an ornamental nursery in Italy. A polyphasic approach, including morphological and cultural observations, sequencing the ITS-rDNA region, the Pheca and the mitochondrial coxI genes, multiplex PCRs with primers specific for P. nicotianae or P. cactorum, as well as random amplified polymorphic DNA–polymerase chain reaction, was used to characterize these isolates. On the basis of morpho-cultural and molecular analyses, the isolates from Stoechas lavender were identified as Phytophthora × pelgrandis, a natural hybrid of P. nicotianae × P. cactorum previously reported in other European countries, the Americas, and Taiwan, as a pathogen of ornamentals and loquat plants. In pathogenicity tests using potted plants of Stoechas lavender, the P. × pelgrandis isolates, similarly to the parental species P. nicotianae, induced the symptoms observed on plants with natural infections and were reisolated only from artificially inoculated plants. Dispersal of P. × pelgrandis on this host could exacerbate the damage caused by Phytophthora root and collar rot, of which the main causal agent presently is P. nicotianae on lavender in Europe. Application of hygienic measures is important to reduce the proliferation and spread of the Phytophthora hybrids

    Italian Physicians' Perceptions about the Role of Asciminib in Later Lines Chronic Myeloid Leukemia in Clinical Practice: A GIMEMA Survey

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    Unmet needs remain in later lines chronic myeloid leukemia (CML): the response rate and the overall survival of resistant patients in the chronic phase who changed a second-generation TKI in the second line with another TKI with similar action are usually poor, while the off-target toxicities and the potential development of mutations increase. The recent approval of asciminib, a STAMP inhibitor, in the third line, has the potential to soon change the therapeutic algorithm for this subset of patients. Here, we report the results of a GIMEMA survey assessing the number of patients currently treated in the third line in Italy, the current approach in later lines by Italian physicians, and the future role of this drug according to the reason to switch to asciminib (resistance and/or intolerance), as well as the perceptions about the future position of this agent

    Benefits of glucocorticoids in non-ambulant boys/men with Duchenne muscular dystrophy: A multicentric longitudinal study using the Performance of Upper Limb test

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    The aim of this study was to establish the possible effect of glucocorticoid treatment on upper limb function in a cohort of 91 non-ambulant DMD boys and adults of age between 11 and 26 years. All 91 were assessed using the Performance of Upper Limb test. Forty-eight were still on glucocorticoid after loss of ambulation, 25 stopped steroids at the time they lost ambulation and 18 were GC naive or had steroids while ambulant for less than a year. At baseline the total scores ranged between 0 and 74 (mean 41.20). The mean total scores were 47.92 in the glucocorticoid group, 36 in those who stopped at loss of ambulation and 30.5 in the naive group (p <0.001). The 12-month changes ranged between -20 and 4 (mean -4.4). The mean changes were -3.79 in the glucocorticoid group, -5.52 in those who stopped at loss of ambulation and -4.44 in the naive group. This was more obvious in the patients between 12 and 18 years and at shoulder and elbow levels. Our findings suggest that continuing glucocorticoids throughout teenage years and adulthood after loss of ambulation appears to have a beneficial effect on upper limb function. (C) 2015 The Authors. Published by Elsevier B.V
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