Control of potato powdery scab caused by Spongospora subterranea by foliage cover and soil application of chemicals under field conditions with naturally infested soil

Powdery scab (PS), caused by Spongospora subterranea, reduces the quality and marketability of potatoes worldwide. Disease symptoms include lesions on the tuber surface and root galling, which may lead to yield losses. In the current study we report a sustainable approach to reduce PS by manipulating soil temperature during tuber initiation. Plant cover with nonwoven fabric significantly reduced PS on tubers by 54%–69% in 2017 and 84%–93% in 2019, compared to the control, and root galling by 96% in 2019, due to an increased average minimum and maximum soil temperature of 1.8 and 4.2 °C in respective years. Additional preplanting soil treatments were also evaluated in naturally infested soil. In 2017, disease incidence and severity were significantly reduced using 2.5 or 5 L a.i./ha fluazinam in broadcast application or in-furrow, and by 0.375 or 0.75 L a.i./ha flusulphamide applied in-furrow. In 2019, disease incidence and severity were significantly reduced by the broadcast application of fluazinam, and 75 kg/ha calcium cyanamide, but the latter had a negative impact on yield. Soil fumigation with metam sodium resulted in a 98% reduction in PS. Root galling was significantly reduced by calcium cyanamide, metam sodium, and fluazinam in the 2019 trial only. Foliar application of resistance-inducing phosphonates combined with fluazinam application had no additive effect on PS incidence and severity. Integrated approaches such as tolerant cultivars, soil testing, preplanting fungicide application, and sustainable means of control such as foliage cover for a short period may be implemented in order to control the disease and minimize damage.     

Phosphate sorption to matrix and fracture wall materials in a Glossaqualf

Phosphate retaining properties of macropore wall materials may influence the extent of phosphate leaching via preferential flow. Phosphate sorption to soil matrix material has been compared with sorption to fracture wall materials consisting of inner iron-oxide depleted albic coatings rimmed by reddish iron-oxide enriched quasicoatings. The latter contains 15 times as much Fe oxide, 2 times as much Al (hydr)oxide and 5–6 times as much total P than the albic material, which represent the most P-depleted material in the profile. Oxalate extractable P (P_o) amounts to of the total P contents of the samples. Smectite predominates in the fracture walls and acid subsoils, but has partly transformed into hydroxy-interlayered smectite (HIS) in the upper limed soil horizons. Langmuir parameters derived from phosphate sorption isotherms show no correlation for sorption to whole soil samples and the corresponding clay fractions. The phosphate sorption capacity at a threshold equilibrium concentration of 10 μM (P_ads^t (10 μM)) is measured as the content of P_o plus the amount of phosphate sorbed during 7 days, and can be related to Al_o+Fe_o: P_ads^t (10 μM)=(0.0404±0.0046)·(Al_o+Fe_o)***+3.569. The P_ads^t (10 μM) values vary between 4 and 14 mmol P kg⁻¹, lowest in the albic fracture walls and highest in the iron enriched quasi-coatings. The sorption capacity of the metal oxide free clay does not appear to correlate with smectite or HIS contents. In total, the clay fraction contributes with about 50% of the whole soil sorption capacity in agreement with 40–60% of the total soil Al_o+Fe_o being present in the clay fraction. At a solution phosphate concentration of 10 μM, the Ap horizon is found to be almost phosphate saturated whereas subsoil horizons including the fractures have phosphate saturations ≤50% and, hence, can strongly sorb P. The low phosphate saturation of fracture walls indicates that they do not act as major sinks of phosphate-rich solutions from topsoil horizons, either due to kinetic constraints, or due to a flow pattern not allowing P-rich solution to percolate fractures.     

Effect of clove (Eugenia caryophyllus) and cinnamon (Cinnamomum zeylanicum) essential oils in Nile tilapia diets on performance,antioxidant power and lipid oxidation in fillets

This study evaluated the addition (0.35 and 0.70 g/kg feed) of clove (EOcl) or cinnamon (EOci) essential oils to Nile tilapia feed for 45 days to assess animal performance, antioxidant capacity and lipid oxidation in fillets. The design was completely randomised with five treatments and three replicates. Antioxidant capacity was determined by the oxygen radical absorbance capacity (ORAC_FL), 2,2‐diphenyl‐1‐picrylhydrazylhydrate (DPPH), ferric reducing ability power (FRAP) and 2,2’‐azino‐bis (3‐ethylbenzothiazoline‐6‐sulphonic acid) (ABTS) assays, and lipid oxidation was determined by the thiobarbituric acid‐reactive substances (TBARs) assay. Animal performance was not altered by adding the essential oils. The fillets treated with 0.35 g/kg of EOcl presented higher antioxidant capacity in the L‐ORAC_FL assay and a 40.3% reduction in lipid oxidation, whereas the EOci provided a pro‐oxidant effect relative to the control treatment. Based on these results, adding 0.35 g/kg of EOcl to the diet for 45 days before slaughter increased the antioxidant capacity and reduced the lipid oxidation of the fillets, contributing to product quality without altering animal performance.     

Dolphins in a bottle: abundance,residency patterns and conservation of bottlenose dolphins Tursiops truncatus in the semi‐closed eutrophic Amvrakikos Gulf,Greece

• 1. Boat surveys were conducted between 2002 and 2005 to study bottlenose dolphins living in the 400 km² Amvrakikos Gulf, western Greece. During 116 survey days, 4705 km of total effort resulted in the individual photo‐identification of 106 animals, through long‐term natural markings on their dorsal fins.
• 2. Mark–recapture analyses based on the M_th model provided estimates of 82 marked individuals in 2003 (95% CI=80–91), 92 in 2004 (95% CI=86–108) and 98 in 2005 (95% CI=94–110). To include the unmarked portion of the population, the proportion of unmarked individuals was computed based on the number of photographs of marked and unmarked dorsal fins. The mean proportion of unmarked animals in the population was 0.338 (95% CI=0.288–0.389). By adding this to the estimate for marked animals in 2005, considered as the most robust, a total population estimate of 148 individuals (95% CI=132–180) was obtained.
• 3. Dolphin encounter rates in 2003–2005 did not show significant variations, and averaged 7.2 groups per 100 km or 72.5 individuals per 100 km. Encounter rates within the Gulf were about one order of magnitude greater than those found for bottlenose dolphins in nearby eastern Ionian Sea coastal waters.
• 4. Mean dolphin density in the Gulf was 0.37 animals km^?2. This relatively high density, together with high levels of site fidelity shown by most individuals, was thought to be related primarily to prey availability, particularly of epipelagic schooling fish.
• 5. The importance of the semi‐closed Amvrakikos Gulf for bottlenose dolphins and other threatened species encourages the adoption of measures aimed to conserve its valuable ecosystems and raise the naturalistic profile of the area, while promoting environment‐conscious development. Meaningful action includes restoring natural hydrology (e.g. freshwater input from rivers), curtailing pollution from various sources, responsible fisheries and aquaculture management, and control of illegal fishing. Interactions between dolphins and fisheries also deserve careful quantitative investigation.

Copyright © 2007 John Wiley & Sons, Ltd.     

Effect of interstock (M.9 and M.27) on vegetative growth and yield of apple trees (cv “Annurca”)

With the purpose of obtaining apple plants with reduced vigour but deep and expanded root apparatus, more adapted for establishment of apple orchards in dry, windy areas and higher altitudes, different interstem/rootstock combinations were compared, using seedling as rootstock and, alternatively, two weak interstocks (M.9 and M.27). For all treatments the plants were grafted at two height from soil (10 and 20 cm), interposing interstock 10 or 20 cm long. Plants with interstock showed lower vegetative growth in comparison with control plants with a reduction of 80% (M.27) and of 50% (M.9) of canopy growth. Moreover, use of interstock determined, as compared with the control plants, an increase of fruit production and average fruit weight. It was noted that increasing the interstock length, caused reduction of plants vigour and fruit production. The results showed that, the combination “Annurca Rossa del Sud”/M.9 (10 cm long)/seedling rootstock (20 cm high) was the most efficient for productivity, early maturing and plant vigour control.     

Study of Biodegradation Processes of BTEX-ethanol Mixture in Tropical Soil

In Brazil, gasoline is currently blended with ethanol and both compounds may contaminate the environment when spills occur. Ethanol preferential biodegradation delays gasoline degradation in the aquifer, as previously observed; in unsaturated soil a delayed recovery of culturable bacteria and removal of residues in the presence of ethanol suggest a similar situation. This study monitors microbial degrading activity in unsaturated soil with BTEX and BTEX-ethanol mixtures under tropical conditions as well as the effects of bioventing on contaminants degradation. Enzymatic activity was quantified by measuring fluorescein-diacetate hydrolysis by microorganisms, which determines total degrading activity in soil. As microbial enhanced activity may alter soil electromagnetic properties, soil dielectric constant shifts were monitored using Time Domain Reflectometry (TDR), while chemical analyses evaluated contamination residues throughout the experiment. Results suggest that ethanol delays BTEX biodegradation and that bioventing may compensate for this delay by providing oxygen for the continuation of microbial activity. Contamination and bioventing stimulated soil microbiota, while culturable populations were inhibited by contamination, showing soil toxicity. The presence of ethanol caused a higher and longer-lasting boost in enzymatic activity; TDR measurements did not follow these activity shifts, proving not to be an adequate tool for evaluating microbial activity in these experimental conditions. Residual BTEX were detected only in ethanol-containing non-ventilated soils after contamination. The set of results suggests that ethanol could delay BTEX degradation because of its constitutive degradation by soil microbiota, but this effect may be bypassed by bioventing.     

Effect of plant phenolics on protein and lipid oxidation in cooked pork meat patties

Rapeseed and pine bark are rich sources of phenolic compounds that have in previous studies been shown to exhibit antioxidant and anti-inflammatory properties. In this study, the antioxidant effect of rapeseed and pine bark phenolics in inhibiting the oxidation of lipids and proteins in meat was tested as a possible functional food application. The cooked pork meat with added plant material was oxidized for 9 days at 5 degrees C under light. The suitable level of plant material addition was first screened by following lipid oxidation only. For further investigations plant materials were added at a level preventing lipid oxidation by >80%. The oxidation was followed by measuring the formation of hexanal by headspace gas chromatography and the formation of protein carbonyls by converting them to 2,4-dinitrophenylhydrazones and measured by spectrophotometer. It was shown that rapeseed and pine bark were excellent antioxidants toward protein oxidation (inhibitions between 42 and 64%). These results indicate that rapeseed and pine bark could be potential sources of antioxidants in meat products.     

Caffeic and chlorogenic acids in Ilex paraguariensis extracts are the main inhibitors of AGE generation by methylglyoxal in model proteins

The present study concentrates on the evaluation of the anti-glycation effect of some bioactive substances present in yerba maté (Ilex paraguariensis): 5-caffeoylquinic acid, caffeic acid and a sapogenin (oleanolic acid). Bovine serum albumin and histones were incubated in the presence of methylglyoxal with or without the addition of 5-caffeoylquinic acid, caffeic acid and oleanolic acid. After the incubation period, advanced glycation end product (AGE) fluorescence spectra were performed and protein structural changes were evaluated by Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis. Chlorogenic acid, caffeic acid are the main substances responsible for the anti-glycation effect of maté tea.     

Output of gastrointestinal nematode eggs in the feces of captive gazelles (Gazella dama mhorr, Gazella cuvieri and Gazella dorcas neglecta) in a semiarid region of southeastern Spain.

Feces from 62 captive African gazelles, including Mhorr gazelles (Gazella dama mhorr), Cuvier's gazelles (Gazella cuvieri), and Dorcas gazelles (Gazella dorcas neglecta), were examined over the course of a year to quantitate nematode egg excretion patterns. Strongyloides sp. eggs appeared only in G. dama during the rainy season. Trichostrongylidae egg excretion showed a marked seasonal variation, with very low levels during the dry and hot period, a finding that is probably attributable to hypobiosis of the predominant species (Camelostrongylus mentulatus). Eggs of the Nematodirus sp., predominantly Nematodirus spathiger, were excreted throughout the year. No seasonal pattern was observed in Trichuris sp. egg excretion.