Use of molecular identification techniques for the study of parasitoids of the chestnut gall wasp

The chestnut gall wasp Dryocosmus kuriphilus Yasumatsu (Hymenoptera, Cynipidae) is considered as a major pest of Castanea species worldwide. A three-year monitoring of the indigenous parasitoids of this pest was performed by collecting specimens inside the galls. Each specimen was processed by molecular analysis. DNA was analysed by amplification and sequencing of the COI gene, coding for cytochrome c oxydase subunit 1. Each sequence was compared with reference sequences from adults sampled in Sardinia and those present both in GenBank and Barcode of Life Database (BOLD). This procedure enabled us to identify all immature life stages, included larvae and pupae that cannot be identified otherwise. The identified species belong to 7 genera of the superfamily Chalcidoidea: Eupelmus (Eupelmidae), Eurytoma and Sycophila (Eurytomidae), Ormyrus (Ormyridae), Mesopolobus (Pteromalidae), Megastigmus and Torymus (Torymidae). Among the identified taxa we found a few unknown species and also some sibling ones. These findings will make it possible to elucidate the relationships between the indigenous parasitoids and the host pest and to verify the spreading of the introduced exotic antagonist Torymus sinensis in order to plan new control strategies

Quality of life aspects of a low protein diet using GMP in patients with phenylketonuria

Objective: To assess some quality of life (QOL) aspects of a low protein diet, using glycomacropeptide (GMP) as a protein substitute in patients with phenylketonuria (PKU). Methods: This was a multicentre, prospective observational cohort, study. Metabolic control, nutritional parameters, and dietary adherence were assessed in patients with PKU before (T0), and six months after (T6) starting a low protein diet using GMP. Selected items from the PKUQOL questionnaire were used to assess patients’ acceptance of their modified diet. Results: 18 patients from three Italian Centres, completed the study. With the exception of LDL-cholesterol and vitamin 25OH-D concentrations, there were no differences between T0 and T6 in metabolic or nutritional parameters. Data suggested that patients have a good acceptance of protein substitutes containing GMP, probably because of their improved palatability. Conclusions: According to our patients’ responses to items related to dietary regimen, GMP based protein substitutes do not appear to significantly affect QOL

First report of Neofusicoccum australe associated with grapevine cordon dieback in Italy

This is the first report of Neofusicoccum australe associated with grapevine dieback in Italy. Fungal isolates obtained from symptomatic tissues were identified on the basis of morphological and cultural characteristics as well as ITS sequence data. Pathogenicity was verified by inoculation of excised green grapevine shoots from cv. Cannonau under controlled laboratory condition

The ocular albinism type 1 protein, an intracellular G protein-coupled receptor, regulates melanosome transport in pigment cells

The protein product of the ocular albinism type 1 gene, named OA1, is a pigment cell-specific G protein-coupled receptor exclusively localized to intracellular organelles, namely lysosomes and melanosomes. Loss of OA1 function leads to the formation of macromelanosomes, suggesting that this receptor is implicated in organelle biogenesis, however the mechanism involved in the pathogenesis of the disease remains obscure. We report here the identification of an unexpected abnormality in melanosome distribution both in retinal pigment epithelium (RPE) and skin melanocytes of Oa1-knock-out (KO) mice, consisting in a displacement of the organelles from the central cytoplasm towards the cell periphery. Despite their depletion from the microtubule (MT)-enriched perinuclear region, Oa1-KO melanosomes were able to aggregate at the centrosome upon disruption of the actin cytoskeleton or expression of a dominant-negative construct of myosin Va. Consistently, quantification of organelle transport in living cells revealed that Oa1-KO melanosomes displayed a severe reduction in MT-based motility; however, this defect was rescued to normal following inhibition of actin-dependent capture at the cell periphery. Together, these data point to a defective regulation of organelle transport in the absence of OA1 and imply that the cytoskeleton might represent a downstream effector of this receptor. Furthermore, our results enlighten a novel function for OA1 in pigment cells and suggest that ocular albinism type 1 might result from a different pathogenetic mechanism than previously thought, based on an organelle-autonomous signalling pathway implicated in the regulation of both membrane traffic and transport

Bacterial stem rot in greenhouse pepper (<i>Capsicum annuum</i> L.) in Sardinia (Italy): occurrence of <i>Erwinia carotovora</i> subsp. <i>carotovora</i>

An unusual bacterial disease was observed in pepper plants during research carried out in greenhouses in central-north Sardinia. The characteristics were: the presence of lesions and exudates on stems, soft rot of the pith, and a brownish-black colour in the petioles and leaf-veins. Only two isolates of 21 were pathogens. One was obtained from exudate present on the stem and the other from pith. Experimental infections revealed that the bacterial isolates were particularly aggressive in the stems and fruit of pepper and tomato. Biochemical, physiological and serological tests in conjunction with fatty acid profile analysis confirmed that they were Erwinia carotovora subsp. carotovora (Jones) Bergey et al. The product of 434 bp polymerase chain reaction (PCR) enabled a preliminary identification of isolates to be made. Restriction fragment length polymorphism (RFLP) analysis of amplification products showed that the isolates DPP 23ef and DPP 24m, strain type CFBP 2046 and DPP 281, isolated from pepper fruit, belonged to the RFLP group 12, whereas DPP 29, also isolated from pepper fruit, was included in RFLP group 1. Measures to prevent and control this recently introduced disease are suggested in the conclusion of this paper

Phenotypic and genetic characterization of <i>Erwiniua carotovora</i> spp. <i>carotovora</i> (Jones) Bergey <i>et al.</i> isolates from grafted tomato in Sardinia, Italy

A disease symptomatically similar to that caused by Erwinia carotovora occurred on “Cuore di Bue” and “Cencara” tomato plants grafted on “Beaufort” and “He-Man”, or ungrafted, in greenhouses in Sardinia (Italy). Symptoms were: dark brown/black longitudinal stem lesions, soft stem rot, pith breakdown of the stems, hollow stems, vascular tissue discoloration, wilting and collapse of the plants. Numerous bacterial colonies from stem tissues were isolated on yeast extract salts (YS) medium. Seven isolates (DPP As-1, DPP As-2, DPP As-3, DPP As-14, DPP Pu6, DPP Pu7 e DPP Pu8) were selected on the basis of their ability to cause rot on potato pieces and a hypersensitivity reaction in “White burley” tobacco leaves. Pathogenicity tests revealed that five of these isolates infected artichoke, basil, dwarf bean, fennel, marrow, melon, pepper, eggplant, grafted and ungrafted tomato, and white cabbage. Of the remaining two isolates, one (DPP As-1) did not infect white cabbage, and the other (DPP Pu8) did not infect basil, marrow or white cabbage. Phenotypic properties and ELISA, also performed on naturally infected tissues, revealed that all the isolates were E. c. ssp. carotovora (Jones) Bergey et al. PCR-RFLP analysis placed two (DPP As-2 and DPP As-3) of the seven isolates in RFLP group 8. Five isolates belonged to a hitherto unknown RFLP group. Prevention and control measures for this disease are suggested

Identification and characterization of Burkholderia isolates obtained from bacterial rot of saffron (<I>Crocus sativus</I> L.) grown in Italy

<p>Twenty five isolates of <em>Burkholderia gladioli</em>, the causal agent of a bacterial disease recently reported on saffron (<em>Crocus sativus </em>L.) grown in central Sardinia (Italy), were characterized using different approaches. The characteristic symptoms of the disease on saffron plants were rot of emerging shoots and leaves and spots on leaves and corms. In the field, the disease was destructive and reduced flowering by about 80%. Two types of colonies of bacteria cultured from affected plants were selected on the basis of their characteristic morphology and pigment production on nutrient-glucose-agar. One type was round, wrinkled, and producing yellowish pigment; while the second was round, smooth and without pigment. All 25 selected isolates were pathogenic on saffron leaves and corms. Ten were pathogenic on gladiolus and lily leaves. None of the tested isolates was pathogenic on onion plants. The isolates were characterized by conventional tests, Biolog, PCR and PCR-RFLP analysis. Conventional tests and PCR identified all isolates as <em>B. gladioli</em>. PCR-RFLP analysis of 16S rDNA products digested with the three restriction enzymes <em>Alu </em>I, <em>Dde </em>I and <em>Bss </em>KI, identified ten of the isolates as <em>B. gladioli </em>pv. <em>gladioli</em>. Sequencing and comparison of the 16S rDNA PCR products confirmed that ten of of the isolates were <em>B. gladioli </em>and the remaining 15 were an unidentified <em>Burkholderia </em>species. Sequencing the gene encoding for b-subunit polypeptide of DNA gyrase (<em>gyrB</em>) did not assist identification of these isolates. This study suggests that other <em>Burkholderia </em>species are involved with bacterial softrot of saffron in Sardinia, and further studies are in progress to verify this hypothesis.</p

Identification and characterization of Burkholderia isolates obtained from bacterial rot of saffron (Crocus sativus L.) grown in Italy

Twenty five isolates of Burkholderia gladioli, the causal agent of a bacterial disease recently reported on saffron (Crocus sativus L.) grown in central Sardinia (Italy), were characterized using different approaches. The characteristic symptoms of the disease on saffron plants were rot of emerging shoots and leaves and spots on leaves and corms. In the field, the disease was destructive and reduced flowering by about 80%. Two types of colonies of bacteria cultured from affected plants were selected on the basis of their characteristic morphology and pigment production on nutrient-glucose-agar. One type was round, wrinkled, and producing yellowish pigment; while the second was round, smooth and without pigment. All 25 selected isolates were pathogenic on saffron leaves and corms. Ten were pathogenic on gladiolus and lily leaves. None of the tested isolates was pathogenic on onion plants. The isolates were characterized by conventional tests, Biolog, PCR and PCR-RFLP analysis. Conventional tests and PCR identified all isolates as B. gladioli. PCR-RFLP analysis of 16S rDNA products digested with the three restriction enzymes Alu I, Dde I and Bss KI, identified ten of the isolates as B. gladioli pv. gladioli. Sequencing and comparison of the 16S rDNA PCR products confirmed that ten of of the isolates were B. gladioli and the remaining 15 were an unidentified Burkholderia species. Sequencing the gene encoding for b-subunit polypeptide of DNA gyrase (gyrB) did not assist identification of these isolates. This study suggests that other Burkholderia species are involved with bacterial softrot of saffron in Sardinia, and further studies are in progress to verify this hypothesis

Studio della comunità ectomicorrizica di una sughereta della Sardegna = Study of the ectomycorrhizal community in a cork oak stand of Sardinia

The research was carried out in order to characterise the ectomycorrhizal community of a cork oak stand in Sardinia, composed by plants of Quercus suber, some plants of Q. ilex and shrubby species, mainly Arbutus unedo, Cistus spp. and Erica spp. In the cork oak 20 areal transepts were done in order to map the vegetal species forming ectomycorrhizae, including also those of the genus Erica. A soil sample was taken from the centre of each transept in order to analyse the ectomycorrhizal fungal community. In total 4700 colonized root tips were examined and ascribed to 75 different morphotypes on the basis of morpho-anatomic and biomolecular analyses. 69 of these morphotypes were identified at family, genus or species level by sequencing of the ITS region. Data obtained in this study allowed us to describe the structure of the ectomycorrhizal community and to estimate the efficiency of the sampling method, the correlation between the biodiversity of the two symbiont communities and the richness in species. The fungal community is dominated by Cenococcum geophilum; other widespread species are Lactarius chrysorrheus and one species of Thelephoraceae, whereas several other species are present occasionally. The most representative genera were Lactarius, Russula, Sebacina and Tomentella. The dominant families were Cortinariaceae, Russulaceae, Sebacinaceae, Thelephoraceae and to a less extent Tuberaceae