Influence of film wrapping and fludioxonil application on quality of pomegranate fruit

Pomegranates are sensitive to low temperatures. When fruit are exposed to temperatures below 5–6 °C chilling injury appears as pitting of the skin, browning of the white segments separating the arils and discoloration of the arils, and husk scald, which generally is more severe at temperatures of 6–10 °C. The main objective of this work was to assess the effectiveness of individual film packaging, applied as a stand alone treatment or in combination with fludioxonil, on reducing the occurrence of husk scald, weight loss and decay. Fruit were dipped in an aqueous mixture containing 600 mg L^?1 fludioxonil, wrapped or not wrapped with a polyolephinic heat-shrinkable film and stored at 8 °C and 90% RH for 6 or 12 weeks plus one additional week of simulated shelf-life at 20 °C and 65–70% RH. Respiration rate decreased both in cold storage and at 20 °C. Ethylene production was not detected during cold storage; its rate increased upon transfer to 20 °C, but results were inconsistent. Control fruit deteriorated at a very high rate, due to excessive weight loss, skin browning and decay. Film wrapping almost completely inhibited weight loss and husk scald and preserved fruit freshness for the whole storage time. There was no statistical difference in decay incidence between wrapped and control fruit after 6 or 12 weeks of storage and after the first shelf-life, while after the second shelf-life, wrapped fruit had significantly higher decay levels. By contrast, fludioxonil, both alone and in combination with wrapping, effectively controlled mold development, resulting in 50–67% less decay than control fruit after 12 weeks at 8 °C plus one week shelf-life. Control fruit showed minor changes in nutritional compounds as well as in total polyphenols, anthocyanins and antioxidant activity, while higher losses were detected in film-wrapped fruit during storage at 20 °C.     

Detection of helicobacter candidatus suis by PCR in oesophagogastric ulcers of swine in Italy

The aim of this study was to evaluate by PCR the presence of Helicobacter spp. in gastric mucus from the fundic region of the stomach and to investigate its role in oesophagogastric ulcers in swine bred and regularly slaughtered in Piedmont (Northern Italy). Stomachs from 595 regularly slaughtered swine were subjected to gross pathological examination in order to evaluate the presence of gastric ulcers (revealed in 75 cases, 12.6%). Histopathological examination was performed to better characterise erosions and ulcers. DNA extracted from gastric mucus collected from all the ulcer-affected and from 25 normal stomachs was submitted to PCR using Helicobacter spp. 16S rRNA gene target primers. Sixty-three percent (47/75) of the affected stomachs was positive as well as 24% (6/25) of the non-affected ones. Sequence analysis from 5 positive samples showed 99% homology with Helicobacter candidatus suis 16S ribosomal RNA gene.     

Logistic regression modeling of cropping systems to predict fumonisin contamination in maize

The aims of this research were to monitor the presence of fumonisins in maize crops in northern Italy over a 6 year period, to study the role of the cropping system on fumonisin levels, and to contribute to the development of a predictive system for fumonisin contamination. In the 6 year period from 2002 to 2007, 438 maize samples were collected in five regions, supported by agronomic data, and analyzed for fumonisin content. Fumonisin was detected in almost all of the grain samples, but 2007 was less and 2005 more contaminated compared to the other years. Preceding crop, maturity class of hybrids, nitrogen fertilization, sowing and harvest week, and grain moisture significantly affected the level of contamination. The logistic regression developed explained around 60% of variability with major roles for longitude, maturity class, and growing weeks. The function can be used to quantify the effect of these factors in a predictive system.     

The pathology of mitral valve prolapse in dogs

The authors present investigations of the prolapse of the mitral valves in dogs. In 18 cases there were dogs with a prolapse, in 6 dogs there was a prolapse of the tricuspid valves, and in 3 cases a prolapse of both valves was observed. In all cases prolapse occurred together with endocardiosis of the valves or as a consequence of it.     

Epidemiology of Toxin-Producing Fungi and Ochratoxin a Occurrence in Grape

Fungi responsible for ochratoxin A (OTA) production have been studied especially on cereals, where Penicillium verrucosum and Aspergillus ochraceus are to be considered the main producers. Until 1998, these fungi were also believed to be responsible for the production of the toxin in grape, but OTA-producing A. carbonarius and A. niger were identified in dried vine fruits in 1999. Further studies pointed out that mycoflora potentially responsible for the presence of OTA in grapes are present in the field. Aspergilli are dominant to Penicillia, and among these Aspergilli section Nigri. A. carbonarius probably plays an important role because of the high percentage of positive strains and the amount of OTA produced. Aspergilli section Nigri are present on grape bunches early in the season and their frequency increases during later growth stages. At early veraison and ripening, the incidence of colonised berries is more related to the year than to the growth stage, but not to visible symptoms, since it is normal to isolate fungi from intact berries. Differences in ochratoxin content of berries have been detected between years, when the same vineyards, managed in the same way, showed high levels (1999) or the absence (2000) of the toxin. The results suggest that meteorological differences between years and grape-growing areas are responsible for differences in OTA levels, but the data are at present insufficient to draw firm conclusions.     

Effects of fungicide application on physiological and molecular responses of grapevine (Vitis vinifera L.): a comparison between copper and sulfur fungicides applied alone and in combination with novel fungicides

BACKGROUND

Chemical products against fungi and oomycetes pose serious environmental issues. In the last decade, the use of less impacting active ingredients was encouraged to reduce chemical inputs in viticulture. In this study, the effect of different antifungal compounds on grapevine agronomic, physiological, and molecular responses in the vineyard was evaluated in addition to protection against powdery and downy mildews.

RESULTS

In 2 years and in two Vitis vinifera cultivars (Nebbiolo and Arneis), a conventional crop protection approach, based on traditional fungicides (sulfur and copper), was compared to combined strategies. A well-known resistance inducer (potassium phosphonate), Bacillus pumilus strain QST 2808 and calcium oxide, both active ingredients whose biological interaction with grapevine is poorly characterized, were applied in the combined strategies in association with chemical fungicides. Despite a genotype effect occurred, all treatments optimally controlled powdery and downy mildews, with minimal variations in physiological and molecular responses. Gas exchange, chlorophyll content and photosystem II efficiency increased in treated plants at the end of season, along with a slight improvement in the agronomic performances, and an activation of molecular defense processes linked to stilbene and jasmonate pathways.

CONCLUSION

The disease control strategies based on potassium phosphonate, Bacillus pumilus strain QST 2808 or calcium oxide combined with traditional chemical compounds did not cause severe limitations in plant ecophysiology, grape quality, and productive yields. The combination of potassium phosphonate and calcium oxide with traditional fungicides can represent a valuable strategy for reducing copper and sulfur inputs in the vineyards, including those organically managed. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

Comparison of integrated field programmes for the reduction of fumonisin contamination in maize kernels

Fusarium verticillioides is a common maize pathogen which causes diseases on ears and synthesis of the mycotoxins, fumonisins, in kernels. Fumonisin production is influenced by both environmental conditions and agricultural inputs during growth and maturation of the maize plant. The aim of this research was to evaluate the effect of crop management techniques on fumonisin contamination in maize kernels. Experiments were conducted in Northern Italy during 2006 and 2007 using two maize hybrids with different precocity. Factors evaluated were seed planting time (March versus May), plant density (65,000 plants versus 80,000 plants per ha), N fertilization (200 kg N versus 400 kg N per ha), and chemical treatment to control European maize borer (ECB) (yes versus no). These factors were analyzed were as follows: (T1) May sowing, high plant density and N fertilization, (T2) March sowing time, high plant density and N fertilization, (T3) March sowing time, low plant density and balanced N fertilization, (T4) the same agronomic techniques as T3 plus a chemical treatment to control European maize borer. Ears were analyzed morphologically for ECB incidence and severity. Subsequently, kernels were analyzed chemically for fumonisins. Fumonisin contamination was reduced by 57%, 69% and 86% for T2, T3 and T4, respectively, compared to T1. This study clearly underlines that the application of good agricultural practices (GAP) in crop management strategies can effectively control fumonisin contamination of maize kernels.     

Effect of foliar treatments to durum wheat on flag leaf senescence, grain yield, quality and deoxynivalenol contamination in North Italy

Since the production of durum wheat in the drier areas of the Mediterranean Basin is characterized by high variability in terms of yield and grain quality, there is also considerable interest in developing durum wheat in the northern regions, where the pedo-climatic conditions can offer the possibility of obtaining grain yields with higher technological quality and stability. However, the climatic conditions in the northern regions make durum wheat more prone to fungal foliar disease, particularly to Septoria Tritici Blotch (Septoria tritici Rob.) and to Fusarium Head Blight (Fusarium graminearum Petch and Fusarium culmorum Sacc.), with the consequent occurrence of DON in grains.Field experiments have been conducted over two growing seasons at four sites in North West Italy to evaluate the effect of fungicides and foliar nitrogen fertilizer application on durum wheat yield and grain quality. Five combinations of foliar application were compared at each site and each year (untreated control, azole fungicide application at heading, strobilurin fungicide at the stem elongation stage and/or at heading, the addition of a foliar N fertilizer to a fungicide programme). The following parameters were analysed: Septoria Tritici Blotch (STB) severity, flag leaf greenness using a chlorophyll meter, grain yield, test weight, grain protein content, ash content, vitreousness, Fusarium Head Blight (FHB) incidence and severity and deoxynivalenol (DON) contamination. The collected data underline that the cultivation of durum wheat at the climatic conditions of North Italy is actually risky and needs a direct control of fungal disease, which would be able to reduce the development of both foliar and head attacks. The double treatment, with a strobilurin application during the stem elongation stage and azole at heading, results to be an essential practice and showed advantages in terms of the delay of flag leaf senescence (+27%), STB control (+31), FHB control (+11%), yield (+32%) and DON contamination (−45%), compared to the untreated control. Other foliar treatments at heading, such as strobilurin or foliar N fertilizer applications, do not seem to provide any further advantage, for either grain yield or quality. No significant effect of fungicide or foliar N fertilizer application was recorded on the protein or ash concentration or vitreousness.     

A decision tool for evaluating the agronomic risk of exposure to fumonisins of different maize crop management systems in Italy

Fumonisins constitute a group of carcinogenic metabolites produced mainly by Fusarium verticillioides, the most common fungi associated with maize grain. The limits fixed for fumonisins in maize for food and feed by the European Union (EU) could represent a serious problem for maize areas in the south of Europe where F. verticillioides encounters extremely favourable meteorological and environmental conditions for its life cycle. Prevention strategies through pre-harvest agronomic management can achieve the quality and safety standards required by EU regulations.On the basis of results from agronomic field trials conducted in the North of Italy, the first version of an agronomic decision tool has been created to help farmers, collectors and processors manage fumonisin contamination in order to respect the EU fumonisin limits and the constraints required by a given market outlet. The tool is based on the concept of agronomic exposure to fumonisin risk (AEFR), which is a qualitative evaluation of the impact that a crop management system can have on fumonisin contamination.The validation has shown the validity of the decision tool, which was able to correctly classify the crop management systems of real farms according to their agronomic exposure to fumonisin risk: increasing levels of fumonisin contamination corresponded to increasing AEFR levels.