Wood hydraulic and mechanical properties induced by low water availability on two ornamental species Photinia × fraseri var. Red Robin and Viburnum opulus L.

Deficit irrigation at the nursery stage induces drought acclimation through the establishment of avoiding mechanisms and hardening processes. In this experiment, we hypothesized that water deficit would affect wood hydraulic conductivity and mechanical properties with effects on the leaf water potentials of two ornamental species, Photinia × fraseri var. Red Robin and Viburnum opulus L.The experiment was conducted in a nursery (Pistoia, Italy) during summer 2011. Individuals were arranged in three plots under three watering regimes. The control plot (C) received an amount of water replacing that lost via evapotranspiration, while two plots were maintained under severe water deficit (SWD = 33% C) and moderate water deficit (MWD = 66% C).Water deficits reduced stem diameter in both species without changing wood density (D). Concerning mechanical properties, stiffness (E) and strength (YS) of Photinia resulted higher in Photinia than in Viburnum, which did not show differences between treatments in either E or YS, whereas in Photinia, E was lower in SWD (P < 0.05) than in C. Photinia was also characterized by higher k without significant differences between treatments while Viburnum showed a lower conductivity and a significant reduction of k_h under SWD (P < 0.05). Despite this, in field conditions the two species had similar behaviour concerning the leaf water status, showing a reduction of Ψ under SWD.A longer acclimation period would probably be necessary to induce major changes in wood mechanical properties, but the similarity of responses on leaf water status in MWD and C might indicate that a reduction to 66% of water need might be sufficient to maintain the level of turgor necessary for plant physiological functioning.     

Degradation of dicarboximidic fungicides in wine. Part II: Isolation and identification of the major breakdown products of chlozolinate,vinclozolin and procymidone

The main degradation products formed from the dicarboximidic fungicides chlozolinate, vinclozolin and procymidone in wine have been isolated and identified using spectroscopic and chromatographic methods. The fungicides were added to wine after fermentation. Chlozolinate underwent a rapid hydrolytic loss of the ethoxy-carbonyl substituent, to give an oxazolidine that underwent hydrolytic cleavage to give 3′,5′-dichloro-2-hydroxypropanilide. The oxazolidine ring of vinclozolin underwent a similar hydrolysis to give the corresponding anilide 3′,5′-dichloro-2-hydroxy-2-methylbut-3-enanilide. Both these anilides were stable in wine for 150 days. A different degradation behaviour was observed with procymidone and led to the formation of 3,5-dichloroaniline (3,5-DCA), which, in turn, broke down but the derivatives could not be isolated. After consideration of the different behaviours of the fungicides on degradation in wine and in aqueous ethanol at pH4, together with their kinetic data, breakdown pathways are proposed.     

Classification and class-modeling of "Riviera Ligure" extra-virgin olive oil using chemical-physical parameters

The Protected Designation of Origin (PDO) "Riviera Ligure" for extra-virgin olive oils from Liguria specifies three additional geographical mentions corresponding to three different geographical areas. To obtain a complete characterization of this typical Italian product, 217 samples of olive oils produced in this North Italian region during 1998/99 and 1999/2000 were analyzed. For each sample 31 variables were determined by chemical-physical analyses, and the data were subjected to a multivariate statistical analysis. For the 1998/99 crop, characterized by favorable climatic conditions, class-models of the three geographical areas were obtained with good predictive ability, also considering the influence of the month of olive harvesting. The oil samples from the 1999/2000 crop were similarly studied, but bad climatic conditions and a widespread Dacus oleae infestation leveled out the peculiar features of the oils produced in the three areas.     

LC/DAD/ESI/MS method for the determination of imidacloprid, thiacloprid, and spinosad in olives and olive oil after field treatment

The behavior in the field and the transfer from olives to olive oil during the technological process of imidacloprid, thiacloprid, and spinosad were studied. The extraction method used was effective in extracting the analytes of interest, and no interfering peaks were detected in the chromatogram. The residue levels found in olives after treatment were 0.14, 0.04, and 0.30 mg/kg for imidacloprid, thiacloprid, and spinosad, respectively, far below the maximum residue levels (MRLs) set for these insecticides in EU. At the preharvest interval (PHI), no residue was detected for imidacloprid and thiacloprid, while spinosad showed a residue level of 0.04 mg/kg. The study of the effect of the technological process on pesticide transfer in olive oil showed that these insecticides tend to remain in the olive cake. The LC/DAD/ESI/MS method showed good performance with adequate recoveries ranging from 80 to 119% and good method limits of quantitation (LOQs) and of determination (LODs). No matrix effect was detected.     

Effects of agrochemical treatments on the occurrence of Fusarium ear rot and fumonisin contamination of maize in Southern Italy

The efficacy of agrochemical treatments, based on three different fungicides combined with an insecticide, was tested in southern Italy for two years on three maize hybrids to control Fusarium ear rot of maize and the accumulation in the maize kernels of the carcinogenic mycotoxins fumonisins. Insect damage incidence and severity, disease incidence and severity, identification of Fusarium species and levels of fumonisin contamination in kernels were determined. Field trials showed in both years that natural colonization of maize kernels by the fumonisin producing species Fusarium proliferatum and F. verticillioides (up to 81.5 and 26.5%, respectively) and total fumonisin contamination (up to 68.2 μg g⁻¹) were highly severe. For all hybrids and in both years, the treatment with the insecticide applied alone reduced the insect damage severity consistently and the content of fumonisins in the kernel only in half of the cases, whereas fungicide treatments applied in combination with the insecticide showed a further significant reduction of fumonisin contamination in the three hybrids and in both years.     

Chlorophyll a fluorescence analysis along a vertical gradient of the crown in a poplar (Oxford clone) subjected to ozone and water stress

An experiment in open-top chambers was carried out in summer 2008 at Curno (Northern Italy) in order to study the effects of ozone and mild water stress on poplar cuttings (Oxford clone). In this experiment direct fluorescence parameters (JIP-test) were measured in leaves from different sections of the crown (L: lower; M: medium; U: upper parts of the crown). The parameters considered were calculated at the different steps of the fluorescence transient, and include maximum quantum yield efficiency in the dark-adapted state (F(v)/F(M)); the L-band, at 100?∝?s, that expresses the stability of the tripartite system reaction centre-harvesting light complex-core antenna; the K-band, at 300?∝?s, that expresses the efficiency of the oxygen-evolving complex; the J-phase, at 2 ms, that expresses the efficiency with which a trapped exciton can move an electron into the electron transport chain from Q(A)(-) to the intersystem electron acceptors; the IP-phase, which expresses the efficiency of electron transport around the photosystem 1 (PSI) to reduce the final acceptors of the electron transport chain, i.e., ferredoxin and NADP; and finally the performance index total (PItot) for energy conservation from photons absorbed by PSII to the reduction flux of PSI end acceptors. The main results are: (i) different dynamics were observed between leaves in the lower section, whose PItot decreased over time, and those in the upper sections in which it increased, with a dynamic connected to the leaf age; (ii) ozone depressed all the considered fluorescence parameters in basal leaves of well-watered plants, while it had little or no damaging effect on medium-level or upper-section leaves; (iii) PItot and IP-phase increased in upper leaves of plants subjected to ozone stress, as well as the net photosynthesis; (iv) water stress increased PItot of leaves in all levels of the crown. The results suggest that ozone-damaged poplar plants compensate, at least partially, for the loss of photosynthesis with higher photosynthetic rates in young leaves (in the upper section of the crown), more efficient to fix carbon.     

A SNP mutation affects rhizomania-virus content of sugar beets grown on resistance-breaking soils

Rhizomania is one of the most devastating biotic stresses affecting sugar beet (Beta vulgaris L.). It is caused by Beet necrotic yellow vein virus (BNYVV) vectored by the plasmodiophorid Polymyxa betae K. The only means available to control the disease is the use of genetically resistant varieties. “Rizor” or “Holly” (Rz1) and WB42 (Rz2) have been the most widely used resistance sources in the commercial varieties. Recently, naturally occurring resistance-breaking (RB) rhizomania strains have been identified causing major concerns. The aim of this study was to identify SNP mutations that show associations with resistance to rhizomania in sugar beet plants grown under resistance-breaking (RB)-BNYVV soils. Rhizomania virus content was evaluated by indirect triple-antibody sandwich-ELISA within two F ₂ segregating populations respectively grown on an AYPR and IV-BNYVV strain infected soils. Bulked segregant analysis (BSA) was performed. The resistant and susceptible plants were genotyped with a 384-SNPs panel. Of the 384 SNPs, SNP249 was found to associate with the resistance both to the AYPR strain (R ² = 0.37; P = 0.0004) and to the IV-BNYVV (R ² = 0.09; P = 0.0074). Our results suggested that the SNP249 could be readily applicable for marker-assisted breeding of resistance to AYPR strain of rhizomania.     

Phytate degradation,intestinal microbiota,microbial metabolites and immune values are changed in growing pigs fed diets with varying calcium–phosphorus concentration and fermentable substrates

The present study assessed effects of diets containing varying calcium–phosphorus (CaP) concentration and fermentable substrates on digestibility of diets, intestinal microbiota and immune system using 32 crossbred pigs (initial BW 54.7 kg). In a 2 × 2 factorial arrangement, pigs were fed either a corn–soybean meal (CSB) or corn–field pea (CFP) diet with either low [‐] (4.4 g Ca/kg; 4.2 g total P/kg) or high [+] (8.3 g Ca/kg; 7.5 g total P/kg; supplemented with monocalcium phosphate) CaP content for a period of 9 weeks. In week 8, blood samples were taken, and at the end of the trial, all pigs were euthanized to collect digesta and mesenteric lymphoid tissue. Apparent total tract digestibility (ATTD) of P was greater (p < 0.05) for pigs fed the CaP+ and CFP diets than CaP‐ and CSB diets. The myo‐inositol 1,2,3,4,5,6‐hexakis (dihydrogen phosphate) (InsP₆) concentration in jejunal digesta was higher (p < 0.05) for CaP+ than in CaP‐ fed pigs. In addition, caecal and faecal InsP₅ isomer concentration were greater (p < 0.05) for CSB than CFP diets. In the caecum, gene copy numbers of saccharolytic bacteria, such as Eubacterium rectale and Roseburia spp., as well as SCFA concentration were higher (p < 0.05) for CaP+ than CaP‐ diets. In particular, innate immune cell numbers, such as natural killer cells, dendritic cells, monocytes and neutrophils, were greater (p < 0.05) for CaP+ than CaP‐ fed pigs. Diets high in CaP resulted in higher abundance of potential beneficial bacteria and might promote the first line of defence enhancing the activation of the cellular adaptive immune response, thereby possibly decreasing the risk for intestinal disturbances. These results strongly suggest that both, CaP supply and dietary ingredients differing in fermentability, may beneficially affect gut health through increase in SCFA‐producing bacteria and/or bacteria with anti‐inflammatory properties.     

Using commercial tree nurseries to monitor visible ozone injury—An evaluation

Ozone damage on trees leaves no residue that can be detected analytically; therefore visible assessment is the only easily detectable method for collecting evidence. Here we present an evaluation of an assessment method using damaged detected on trees grown in commercial tree nurseries. The extent of visible ozone injury to susceptible species was investigated on a total of 95 species across 13 nurseries, over four European countries during the 2006 season. Commercial nurseries were chosen because nurseries stock a wide range of accessible, susceptible species which are irrigated when necessary and therefore represent the optimum conditions for assessment of potential risk. Ozone climate at each site was characterised using a combination of passive and active samplers to estimate the accumulated ozone exposure over a threshold of 40 ppb (AOT40). Meteorological and ozone monitoring data were used to calculate cumulative ozone flux using the DO₃SE model (Emberson et al., 2000). Ozone injury was observed in all countries demonstrating that the impacts of ozone are not restricted to countries with higher ozone concentrations; the longer day-length, higher moisture availability and cooler conditions in northern Europe resulted in a greater potential for ozone uptake. Further use of commercial nurseries as an important, unofficial, bioindicator network is warranted.