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In this study, we identified three novel compound classes with potent activity against Plasmodium falciparum, the most dangerous human malarial parasite. Resistance of this pathogen to known drugs is increasing and compounds with different modes of action are urgently needed. One promising drug target is the enzyme 1-deoxy-D-xylulose-5-phosphate synthase (DXPS) of the methylerythritol 4-phosphate (MEP) pathway for which we have previously identified three active compound classes against Mycobacterium tuberculosis. The close structural similarities in the active sites of the DXPS enzymes of P. falciparum and M. tuberculosis prompted investigation of its antiparasitic action, displaying good cell-based activity for all classes. Through structure-activity relationship studies we increased their antimalarial potency, and two classes also show good metabolic stability and low toxicity against human liver cells. The most active compound 1 inhibits the growth of blood-stage P. falciparum with an IC50 of 600 nM. The results from three different methods for target validation of compound 1 suggest intracellular polypharmacy. Similarity-based searches revealed two other possible target enzymes for this compound, which were further analyzed by docking calculations. All inhibitor classes are active against chloroquine resistant strains, confirming a new mode of action.

A survey on the incidence of onion yellow dwarf virus (OYDV) and iris yellow spot virus (IYSV) was carried out over three production cycles of onion ‘Rossa di Tropea’ in Calabria, Italy. OYDV was found to be the prevalent virus. ‘Rossa di Tropea’ seedbeds adjacent to OYDV-infected green onion field had seedlings with 1.76% infection rate determining 36.2% and 98.67% infected plants in the bulbs and in the subsequent seed harvesting times, respectively. When seedbeds were at least one km away from other onion crops seedlings and bulb cultivation had the infection rate close to zero. OYDV was detected in whole plants except the roots and outer desiccated bulb skins. Seed transmission was not detected in ‘Rossa di Tropea’. Early OYDV infection significantly reduced the number and weight of seeds/inflorescence compared to late season infection, while the weight of 100 seeds was not different in the two early and late OYDV infected plants. IYSV was never found in seedbeds. It was always detected first in seed crops (April) than in bulb crops (June), and the final infection rate was higher in seed (2.67%–3.33%) than in bulb crops (0%–0.87%), suggesting there was an internal source of viral inoculum in the field. IYSV was detected in 3/123 apex bulbs randomly collected from stored bulbs and in 12/12 apex fresh bulbs collected at harvest time from infected plants, suggesting the role of bulbs as IYSV inoculum source. On the contrary, randomly collected bulbs (N = 109) from warehouse and bulbs of infected plants (N = 22), transplanted after storage, did not result in IYSV-infected plants.

Histone deacetylases (HDACs) are epigenetic enzymes which participate in transcriptional repression and chromatin condensation mechanisms by removing the acetyl moiety from acetylated ε-amino group of histone lysines and other non-histone proteins. In recent years, HDAC8, a class I HDAC, has emerged as a promising target for different disorders, including X-linked intellectual disability, fibrotic diseases, cancer, and various neuropathological conditions. Selective HDAC8 targeting is required to limit side effects deriving from the treatment with pan-HDAC inhibitors (HDACis); thus, many endeavours have focused on the development of selective HDAC8is. In addition, polypharmacological approaches have been explored to achieve a synergistic action on multi-factorial diseases or to enhance the drug efficacy. In this frame, proteolysis-targeting chimeras (PROTACs) might be regarded as a dual-targeting approach for attaining HDAC8 proteasomal degradation. This review highlights the most relevant and recent advances relative to HDAC8 validation in various diseases, providing a snapshot of the current selective HDAC8is, with a focus on polyfunctional modulators.

Onion yellow dwarf virus (OYDV) is one of the most important viral pathogens of onion. In particular, on 'Rossa di Tropea' onion, granted with Protected Geographical Indication (PGI) trademarks, this pathogen represents the most limiting biotic stress in terms of spread, severity of symptoms and damage, and its detection is necessary to preserve high quality standards and avoid yield losses. A reverse transcription-loop mediated isothermal amplification (RT-LAMP) assay was developed for detection of OYDV. The specificity, sensitivity, repeatability and reproducibility of the assay were validated according to EPPO standard PM7/98 (2). Diagnostic specificity, diagnostic sensitivity and diagnostic accuracy were determined in both leaf and bulb tissues. To enhance the feasibility of a LAMP-based method for field diagnosis, several nucleic acid extraction methods were compared to simplify sample preparation. The results showed the reliability of the method for OYDV detection, with a limit of detection (LOD) comparable to real time reverse transcription polymerase chain reaction (RT-qPCR). The ease of sample preparation, and the more than acceptable LOD, indicated that the RT-LAMP assay could be used in plant pathology laboratories with limited facilities and resources, as well as directly in the field. This work was carried out in the frame of "SI.ORTO" project.

Citrus tristeza virus (CTV) is a severe threat to the citrus industry. Disease symptoms and severity may vary depending on the CTV isolates. These are responsible for the decline of trees grafted on sour orange rootstock, or stem pitting on some citrus commercial cultivars regardless of rootstock. In the Calabria region (Italy), CTV was first reported on cultivars imported from other countries. However, recent observations suggested that natural spread of CTV was occurring and a study was needed to determine the epidemiological status and aphid transmission of CTV in Calabria. The role played by local A. gossypii in the spread of CTV was analyzed in the laboratory using various viral acquisition, inoculation periods with three different CTV isolates. Single aphid vectors acquired CTV after a minimum of 30 min acquisition access period (AAP) and were able to transmit the virus after a 60 min inoculation access period (IAP) to healthy plants. A minimum of four aphid vectors were needed to reach 50% transmission probability. The results suggested that the three tested strains are transmitted by A. gossypii in a semi-persistent mode. The results demonstrated that local A. gossypii population can acquire and transmit efficiently the tested virus isolates with serious implications on the virus spread.

Plant volatile compounds induced by herbivore attack have been demonstrated to provide a signal to herbivore enemies such as parasitic wasps that use these volatiles to locate their hosts. However, in addition to herbivore-induced volatiles, plants often release volatiles constitutively. We assessed the interaction between herbivore-induced and constitutively released volatiles of maize in the attraction of the wasp Cotesia marginiventris that parasitizes herbivorous lepidopteran larvae feeding on maize. Experiments were carried out with olfactometers in which the sources of volatiles were transgenic Arabidopsis thaliana plants overexpressing maize sesquiterpene synthases that produce blends of herbivore-induced or constitutive compounds. We found that the constitutive volatiles of maize terpene synthase 8 (TPS8) were attractive to C. marginiventris, just like the herbivore-induced volatiles of TPS10 studied earlier. A mixture of both the TPS8 and TPS10 volatile blends, however, was more effective in parasitoid attraction, indicating that constitutively released sesquiterpenes enhance the attraction of those induced by herbivores. While C. marginiventris did not distinguish among the volatiles of TPS8, TPS10, nor those of another maize sesquiterpene synthase (TPS5), when these blends were combined, their attractiveness to the wasp appeared to increase with the complexity of the blend.

Among the 15 virus species detected in olive trees, Olive leaf yellowing associated virus (OLYaV) is found with high incidence and frequency in Southern Italy in particular. Effects of OLYaV on virgin olive oil yield and quality of Leccino and Ottobratica cultivars in the Calabria region (Southern Italy) are analyzed. Oil yield, free acidity, number of peroxides, spectrophotometric indices, total content of chlorophylls and carotenoids, total phenol content, composition of the fatty acids, total tocopherols, and total sterols content are determined on oil obtained from olive fruits collected in healthy/virus‐free and OYLaV‐infected trees. Almost all analyzed oil parameters are not statistically different with some exceptions. Oils derived from ‘Ottobratica’ OLYaV‐infected plants have free acidity significantly lower than oil from healthy plants. K₂₃₂ of oil from virus‐free ‘Leccino’ trees is significantly lower than oil from infected trees. Even though some quality parameter differences between healthy and OLYaV‐infected oils are found, it is important to highlight that all oils can be considered in extra virgin olive oil category, within the UE maximum limit acceptance range. Results suggest a no negative interference by OYLaV in oil yield and quality, except for K₂₃₂ values, whereas surprisingly suggest a positive effect of virus infection on free acidity parameter. Practical Applications: Based on the evidence that OYLaV does not interfere negatively in oil yield and quality parameters, it seems appropriate that the European Union Council Directives (2014/96/EU, 2014/97/EU, 2014/98/EU) introduced in the last olive certification scheme only ArMV, CLRV, and SLRSV. The application of compulsory EU directive, in Italy as in other countries, will improve the facilities of olive plants commercialization, guaranteeing enough their sanitary status. The findings here reported support the suggestion that the Italian Ministry of Agriculture could be less restrictive in voluntary Italian regulation (D.M. 20/11/2006). Olive leaf yellowing associated virus (OLYaV) is found with high incidence and frequency especially in Southern Italy. Effects of OLYaV on virgin olive oil yield and quality of Leccino and Ottobratica cultivars in the Calabria region (Southern Italy) are analyzed, including free acidity, number of peroxides, spectrophotometric indexes, total content of chlorophylls, carotenoids and phenol, composition of the fatty acids, total tocopherols and total sterols.

Three-dimensional (3D) target reconstruction provides a more specific description of target features, which would be beneficial for the classification process. In this paper a 3D imaging technique of non-cooperative target acquired by airborne radar system is presented. Traditional two-dimensional (2D) single channel inverse SAR (ISAR) imaging locates each target scattering center in range and Doppler. The third point scatterer coordinate that allows to reconstruct the target in a 3D space is estimated using interferometric phases of two non-parallel baselines and Doppler point scatterer location. The accuracy of the 3D reconstruction depends on the length of the baselines and on the focusing achieved by the 2D imaging process for each channel. The relative movement between the target and the airborne system increases the difficulty to form a well-focused 2D image. The radial component of both radar and target motion affects the image focusing. Moreover traditional image formation method as range/Doppler algorithm introduces further blurring due to the wideband situation. To improve the image quality resulting from standard radial motion compensation techniques and range/Doppler image formation, a method for 2D image processing based on range/velocity data formatting is additionally applied.

Genetic variability and population structure ofCercospora beticola, the causal agent of Cercospora leaf spot in sugarbeet, from four sugarbeet-growing regions of Greece were investigated using growth rate, pathogenicity, and mini- and microsatellite DNA fingerprinting. Mycelial growth and pathogenicity were very diverse within and between groups, and no correlation was found between these features and the geographic origin of the isolates. High diversity was found by micro- and minisatellite fingerprinting, with an average gene diversity of 0.21, and no significant differences among populations. Among the 46 isolates, 45 different genotypes were identified, showing a high degree of genotype diversity. Analysis of the genetic profiles provided no evidence for regional patterns of variation (ΦFST=0.01, P=0.261) and the analysis of molecular variation (AMOVA) revealed that genetic variability was due mainly to variations within (99%) rather than between (1%) populations. Such a low level of genetic differentiation is reflected by a migration rate value Nm of 4.7. The high migration rate cannot be referred to splash dispersed conidia. To justify the absence of a regional structure in these C.beticola populations, we must suppose the existence of a long-distance means of dispersal, such as seed transmission and/or man mediated transmission.

The evolution of citrus tristeza virus (CTV) from outbreaks occurred in Calabria, Italy, was compared with that of CTV outbreaks reported previously in another two proximal Italian regions, Sicily and Apulia. Examination of four genomic regions (genes p20, p25 and p23, and one fragment of open reading frame 1) showed two recombination events, and phylogenetic analysis disclosed two divergent CTV groups in Calabria: one formed by severe and the other by mild isolates. This analysis, together with others involving population genetic parameters, revealed a low migration rate of CTV between the three Italian regions, as well as significant differences in selective pressures, epidemiology and demography, all affecting the genetic structure of CTV populations., This research was carried out in the frame of the national project "Armonizzazione della diagnosi e valutazione del rischio di patogeni da quarantena e nocivi ai vegetali e ai prodotti vegetali (ARNADIA-ARON)", supported by the Italian Ministry of Agriculture. A. Fontana has been the recipient of a postdoctoral fellowship from "Progetto cofinanziato POR Calabria FSE 2007/2013-Obiettivo Operativo M2", and D. E. Debreczeni the recipient of a FPU predoctoral fellowship from the Spanish Ministry of Education and Science.

Exhaustive chromatographic separation of the chloroform portion of the ethanolic extract obtained from Paulownia tomentosa (Thunb). Steud. (Paulowniaceae) fruits has led to isolation of ten C-6 geranylated flavanones tomentodiplacone C–I and mimulone C–E, featured by 3′-methoxy and 4′-hydroxy or 4′-hydroxy substitution of the B-ring of the flavonoid, respectively. The structures of these compounds were determined by using mass spectrometry (including HRMS) and 1D and 2D NMR spectroscopy. The absolute configurations of the compounds at C-2 were determined using circular dichroism. The obtained compounds showed the presence of a geranyl moiety functionalized by a carbonyl, hydroxyl or methoxyl group, or by formation of tetrahydrofuran or fused-pyrane ring, respectively. All of the flavanones described were isolated for the first time from a natural source. The antibacterial activities of selected compounds isolated along with the previously isolated geranylated flavanones were evaluated against a common panel of microbes and MRSA strains. The selected isolated compounds were tested for their ability to affect eukaryotic translation initiation via dual-luciferase reporter assay (firefly and renilla).

Mycelium of Tuber magnatum was obtained in pure culture from mycorrhizas of Tilia cordata, Quercus robur and Corylus avellana . Fifteen mycelia were isolated, which had the same characteristics and behaviour. Among these, one was chosen to be used for growth experiments in solid and liquid media. The best substrate for growth of the mycelium was a modified Melin-Norkrans medium at pH 6. The ability of the isolated mycelium to form mycorrhizas was verified by mycorrhizal synthesis with Populus alba .

Arbuscular mycorrhizal fungi can strongly influence the metabolism of their host plant, but their effect on plant defense mechanisms has not yet been thoroughly investigated. We studied how the principal direct defenses (iridoid glycosides) and indirect defenses (volatile organic compounds) of Plantago lanceolata L. are affected by insect herbivory and mechanical wounding. Volatile compounds were collected and quantified from mycorrhizal and non-mycorrhizal P. lanceolata plants that underwent three different treatments: 1) insect herbivory, 2) mechanical wounding, or 3) no damage. The iridoids aucubin and catalpol were extracted and quantified from the same plants. Emission of terpenoid volatiles was significantly higher after insect herbivory than after the other treatments. However, herbivore-damaged mycorrhizal plants emitted lower amounts of sesquiterpenes, but not monoterpenes, than herbivore-damaged non-mycorrhizal plants. In contrast, mycorrhizal infection increased the emission of the green leaf volatile (Z)-3-hexenyl acetate in untreated control plants, making it comparable to emission from mechanically wounded or herbivore-damaged plants whether or not they had mycorrhizal associates. Neither mycorrhization nor treatment had any influence on the levels of iridoid glycosides. Thus, mycorrhizal infection did not have any effect on the levels of direct defense compounds measured in P. lanceolata. However, the large decline in herbivore-induced sesquiterpene emission may have important implications for the indirect defense potential of this species.

Tuber magnatum Pico is an ectomycorrhizal fungus whose mycorrhizas can be barely distinguished morphologically from those of other related white truffles. Here we describe the use of specific primers based on the T. magnatum ITS sequence for screening mycorrhizas from a large number of growth chambers, greenhouse and nursery samples taken in a long-term survey. This molecular identification technique enabled a new morphological characterization to be set up for T. magnatum mycorrhizas.

Summary The morphology of Ginkgo biloba L. vesicular-arbuscular mycorrhizas (VAM) was investigated in natural conditions and after innoculation with Glomus epigaeum Daniels and Trappe. Morphological features of the infections were similar. The most interesting morphological feature was the presence of abundant intracellular hyphae; intercellular hyphae were rare. Synthesis tests showed the complete Glomus epigaeum life cycle, with the production of sporocarps. Natural infection of Ginkgo biloba roots is considered to be a common phenomenon, and Glomus epigaeum inoculation in controlled conditions increased growth of seedlings.

Concentrations of free and bound amino acids were determined in 1) the mycorrhizal fungus Boletus variegatus Fr. 2) nonmycorrhizal root systems of aseptically grown Pinus sylvestris L. seedlings, and 3) mycorrhizal root systems of seedlings developed aseptically using the two symbionts. Arginine (total) was the major amino acid constituent in the mycelium of B. variegatus (18%–22%) during the exponential phase of growth. While 59%–86% of the available arginine was bound during the acceleration phase of growth, in the logarithmic phase 63%–75% was in the free pool. There were differences in the proportions between the individual amino acids in the bound fraction at different stages of growth suggesting production of diverse proteins. Twenty per cent of the amino acid content of uninfected P. sylvestris root systems was arginine. Infection of the root systems by the fungal symbiont did not result in an increase but a slight decrease in the free arginine content of the composite structure. Almost all other amino acids in the free pool were found in higher concentrations in the mycorrhizal root system. It is suggested that arginine synthesis in B. variegatus is repressed by the arginine available in the host. The mycorrhizal fungus possibly metabolizes the host arginine pool ultimately resulting in more efficient protein synthesis in both the partners.

Anthopsis deltoidea n.gen. et n.sp. of dematiaceous Hyphomycetes, isolated from horticultural soil in Italy, is described. The new fungus is characterized by a peculiar conidial apparatus and by triangular conidia.

(1969). Ectomycorrhizae Formed by Endogone Lactiflua with Species of Pinus and Pseudotsuga. Mycologia: Vol. 61, No. 2, pp. 412-414.