Combined effect of curing followed by acetic acid vapour treatments improves postharvest control of Penicillium digitatum on mandarins

In recent years several alternatives to the chemical control of postharvest decay have been examined but satisfactory levels of control, with a single system, have not been achieved yet. In the present study the results of an integrated postharvest approach are reported. Early and late harvested hybrid mandarin fruit “Fremont” and “Fairchild”, inoculated with Penicillium digitatum (Pers.:Fr.) Saccardo, were cured at 36 °C for 36 h with 95% RH and then fumigated with 0, 5, 15, 25, 50, 75 and 100 μL/L of acetic acid (AAC) vapours for 15 min. Following the treatments, fruit was stored at 20 °C and 80% RH to simulate a marketing period, and after 2 weeks the decay incidence and the visual appearance were evaluated. Curing or fumigations performed alone reduced decay with respect to untreated fruit, but the best control was achieved with combined treatments. For early harvested fruit the lowest decay percentage was obtained by using 75 μL/L with 8.3% and 2.1% of rots for “Fremont” and “Fairchild”, respectively, whereas for late harvested fruit the highest efficacy was observed using 50 μL/L (1.4% and 6.6%). Rind damage as pitting was observed only if fruit was treated with AAC alone at 100 μL/L.     

Natural trematode infestation in feral Nebrodi Black pigs: Pathological investigations

Few studies describe the parasites of pigs bred in the wild state, although pigs are a known reservoir of trematode infestation. This article reports the results of a retrospective study carried out from January 2003 to June 2007 on 3021 Nebrodi Black male and female pigs, regularly slaughtered, aged between 8 months and 4 years. Fasciola hepatica and Dicrocoelium dendriticum flukes were detected in 143 (4.37%) of 3021 livers. The predominant histological features were multifocal to diffuse chronic hepatitis, with fibrosis and severely thickened walls of the bile ducts and chronic parietal, sometimes nodular inflammation. F. hepatica infestation was frequently associated with marked hyperplasia and hypertrophy of the submucosal glands. The study results confirm the important role swine play in the transmission of trematode infestations, indicate the prevalence of these parasites in the Nebrodi Park area, and draw attention to the need for a prophylaxis plan to prevent the spread of infestation to ruminants and humans living in the area.     

Persistent effects of fire-induced vegetation change on energy partitioning and evapotranspiration in ponderosa pine forests

We compared energy fluxes between a site converted from ponderosa pine (Pinus ponderosa) forest to sparse grassland by a severe wildfire 10 years ago and a nearby, unburned forest. We used eddy covariance and associated instruments to measure total radiation, net radiation, albedo, and fluxes of energy into latent heat, sensible heat, and the soil. Total radiation, vapor pressure deficit, and air temperature were similar for each site. Compared to the unburned site, net radiation efficiency (net radiation/total radiation) was 30% lower and albedo 30% higher at the burned site. The magnitude of sensible and latent heats varied seasonally at both sites. Sensible heat was the major component of the energy balance in cold or dry seasons, whereas latent heat was the major component in the warm and wet season. Soil heat flux was the smallest in magnitude of the measured energy fluxes. Compared with the unburned forest, the burn-created grassland generally had lower sensible and latent heats, but greater soil heat flux for both soil cooling in winter and warming in summer. The grassland had similar maximum air temperature as the forest, and warmer surface soil temperature during the summer. Thus, the lower albedo and greater sensible heat of the forest did not produce a warmer site compared with the grassland, apparently because of the cooling effect of greater latent heat in the forest. Our results suggest only small changes in site air temperature, but larger changes in site surface soil temperature by shifts from forest to grassland caused by severe fire in northern Arizona ponderosa pine forests.     

Production of Gynogenetic Plants of Onion (Allium cepa L.) after Crossing with Irradiated Pollen

The possibility of producing gynogenetic plants with pollen inactivated by irradiation was explored for the onion (Allium cepa L.). Two successive experiments included the use of cytoplasmic male sterility, recessive nuclear markers in the female plants and pollen irradiation of 150 Gy. Pollinations were achieved with the aid of flies and all seeds were harvested without the use of embryo rescue. Plantlets with recessive characters could be detected and they contained haploid and diploid cells. The development of these plantlets until flowering was observed under agronomic conditions. The use of doubled haploid (DH) plants in onion breeding is discussed.     

Evaluation of the effect of ranitidine on gastroduodenal contractile activity and gastric emptying in horses

Objective-To determine the effect of ranitidine on gastric emptying in horses. Animals-11 adult horses. Procedures-In vitro, isolated muscle strips from the pyloric antrum and duodenum of 5 horses were suspended in baths and attached to isometric force transducers. Once stable spontaneous contractions were observed, ranitidine or diluent was added at cumulative increasing concentrations. Isometric stress responses were compared. In vivo, 6 horses were assigned to a group in a prospective randomized crossover study design with a wash-out period of 2 weeks between trials. Ranitidine (2.2 mg/kg) or saline (0.9% NaCl) solution was administered IV, and 15 minutes later, acetaminophen (20 mg/kg), diluted in 400 mL of water, was administered via nasogastric tube to evaluate the liquid phase of gastric emptying. Serum acetaminophen concentration was measured at several time points for 3 hours by use of liquid chromatography tandem mass spectrometry. Frequency of defecation was recorded during the 3 hours of the study. Results-Ranitidine increased the contractile activity of the pyloric antrum smooth muscle at a concentration of 10(4) M. No significant effect of ranitidine on plasma kinetics of acetaminophen was identified. Frequency of defecation did not differ between groups. Conclusions and Clinical Relevance-Ranitidine did increase gastric motility in vitro, but no effect on liquid phase gastric emptying was identified in healthy horses by use of the acetaminophen absorption model. Results do not support the use of ranitidine to promote gastric emptying.     

Sodium carbonate treatment induces scoparone accumulation, structural changes, and alkalinization in the albedo of wounded citrus fruits

Following sodium carbonate treatment, accumulation of scoparone (6,7-dimethoxycoumarin) but not scopoletin (6-methoxy-7-hydroxycoumarin) was found in the albedo of wounded fruit from different Citrus sp. and cultivars. Treating wounded mandarin fruit cv. Fairchild with 5% Na(2)CO(3) (SC) lead to a scoparone accumulation in the albedo of 310, 361, and 382 microg g(-1) fresh weight after 7, 10, and 15 days, respectively. Scoparone accumulation was associated with a decrease in decay severity. When oranges cv. Biondo comune wounded and treated with 5% SC were inoculated with Penicillium digitatum or Penicillium italicum conidia 3 days posttreatment, the decay percentage as compared to untreated wounds was reduced by 97.2 and 93.9%, respectively. Observations by scanning electron microscopy of wounded Citrus fruits treated at 20 degrees C with 2, 3, 4, or 5% (w/v) solutions of sodium carbonate showed structural modifications to the albedo as well as damage to 24-48 h old mycelia of P. digitatum, the cause of citrus green mold. Modifications were more evident in orange, lemon, and grapefruit as compared to mandarin fruit. The efficacy of the treatment was strictly related to the SC interaction with the albedo tissue that, in addition to structural changes, significantly increased tissue pH, affecting P. digitatum pathogenicity. The SC remaining as a film on unwounded flavedo had no effect in preventing contact infection by the Penicillia.