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The potential effect of pre-inoculation of processing tomato (Solanum lycopersicum L.) plants with arbuscular mycorrhizal fungi (AMF) on yield and fruit properties was investigated in conventional production. Tomato seeds were sown in seedling trays filled with a substrate non-inoculated (AMF-) or inoculated (AMF+) by selected mycorrhizal strains. Seedlings were transplanted in Terra rossa soil and grown in conditions with mineral fertilization and irrigation. Tomato fruits were sampled at harvest. Tomato plants under both treatments had high levels of mycorrhizal colonization, due to applied inoculum (AMF+) or indigenous (AMF-) inoculum present in the soil. Applied AMF+ treatment increased P and decreased K content in tomato fruits. Content of trace elements such as As and V significantly increased, while Pb content significantly decreased in the fruits of AMF+ when compared to the AMF- treatment. No significant effect of AMF+ treatment was observed on yield, fruit quality (soluble solids, pH, total acidity, fruit firmness), lycopene and antioxidant activity of tomato fruits. The overall results suggest that processing tomato is highly susceptible to the indigenous AMF, while seedlings inoculation with selected AMF improves only total phenolic and P fruit content. This means that AMF have a potential application in commercial processing tomato production, however a targeted adaptation of management decissions is required for more extensive results.

This study investigates the effect of combined sulfur (S) and nitrogen (N) foliar fertilization on leaf S and N concentration, as well as on the growth of olive fruit and on the quantity and quality of olive oil, obtained from two olive cultivars ‘Istarska bjelica’ and ‘Leccino’ in two consecutive years. S and N are some of the most important nutrients, and both play a crucial role in plant oil production. The here-reported fertilization program significantly increased S concentration in leaves without affecting N concentration, which led to an increase in fruit yield and improvement of all fruit morphological parameters. The best oil yield per tree was obtained under the treatment with the highest S/N dose. Oil quality was not affected by S and N supply, and this allowed us to classify all our oil samples as extra virgin (EVOO). Regarding the content of total phenols (TPC) and composition of fatty acid methyl esters (FAME), they remained unaltered under the applied treatments. All investigated fruit morphological parameters, as well as fruit and oil yield, were highly cultivar-dependent. ‘Istarska bjelica’ was characterized as a cultivar with higher fruit mass and pulp percentage, while its stone parameters were lower than those of ‘Leccino’. Consequently, the extraction oil yield obtained from ‘Istarska bjelica’ fruits was much higher. Moreover, environmental conditions had a great impact on fruit and oil quantity. The here-obtained results led us to the conclusion that supply of S and N can enhance oil production without affecting its nutritional quality, a finding that could generate large long-term effects on economic growth in the olive oil sector.

Copper (Cu) locally contaminates soils and might negatively affect growth and yield of crops. A better understanding of plant copper tolerance and accumulation is needed in order to breed more Cu-tolerant or Cu-efficient crops. Cu tolerance was evaluated in different varieties of seven species (Brassica carinata, B. juncea, B. napus, Cynara cardunculus, Helianthus annuus, Nicotiana tabacum and Raphanus sativus) exposed to a series of CuSO4 concentrations (0.1–8 μM CuSO4) in the nutrient solution. Plants were further exposed to 0.1 μM CuSO4 and to their variety-specific concentrations that reduced root growth to 50% of the maximum rate (EC50). Among all the varieties of all the species the EC50 varied from 0.7 up to 3.1 μM Cu. B. carinata was significantly more Cu-sensitive than the other species, which were not significantly different among each other, and B. carinata and H. annuus accommodated significant intra-specific, inter-varietal variation. There were significant differences between species in Cu uptake efficiency and nutrient status. When under EC50 exposure, all the Brassicaceae, except B. carinata, maintained low Cu concentrations in shoots, whereas the other species and B. carinata exhibited significantly increased shoot Cu concentrations, compared to the control. There was no apparent relationship between Cu tolerance and Cu accumulation in roots and shoots, suggesting that the observed variation in tolerance, both between and within species, is not explained by differential exclusion capacity. Discriminant analysis and treatment comparisons suggest possible contribution of lignin, saturated fatty acids, manganese (Mn) and zinc (Zn) in tolerance to high Cu concentrations in shoot.

The potential effect of pre-inoculation of processing tomato (Solanum lycopersicum L.) plants with arbuscular mycorrhizal fungi (AMF) on yield and fruit properties was investigated in conventional production. Tomato seeds were sown in seedling trays filled with a substrate non-inoculated (AMF-) or inoculated (AMF+) by selected mycorrhizal strains. Seedlings were transplanted in Terra rossa soil and grown in conditions with mineral fertilization and irrigation. Tomato fruits were sampled at harvest. Tomato plants under both treatments had high levels of mycorrhizal colonization, due to applied inoculum (AMF+) or indigenous (AMF-) inoculum present in the soil. Applied AMF+ treatment increased P and decreased K content in tomato fruits. Content of trace elements such as As and V significantly increased, while Pb content significantly decreased in the fruits of AMF+ when compared to the AMF- treatment. No significant effect of AMF+ treatment was observed on yield, fruit quality (soluble solids, pH, total acidity, fruit firmness), lycopene and antioxidant activity of tomato fruits. The overall results suggest that processing tomato is highly susceptible to the indigenous AMF, while seedlings inoculation with selected AMF improves only total phenolic and P fruit content. This means that AMF have a potential application in commercial processing tomato production, however a targeted adaptation of management decissions is required for more extensive results., Potencijalni utjecaj inokulacije presadnica industrijske rajčice (Solanum lycopersicum L.) selekcioniranim arbuskularnim mikoriznim gljivama (AMF), na prinos i svojstva ploda, istražen je u konvencionalnoj proizvodnji. Sjeme rajčice posijano je u polistirenske kontejnere s neinokuliranim (AMF-) ili mikorizama inokuliranim (AMF+) supstratom. Presadnice su posađene u crvenicu, u proizvodnim uvjetima s mineralnom gnojidbom i navodnjavanjem. Uzorkovanje plodova industrijske rajčice provedeno je u berbi. Kod oba tretmana utvrđen je visoki postotak kolonizacije selekcioniranim mikorizama (AMF+) i nativnim vrstama (AMF-) prisutnim u tlu. Plodovi rajčice s AMF+ biljaka imali su veći sadržaj P i manji sadržaj K u odnosu na AMF- tretman. Sadržaj As i V bio je signifikantno veći, dok je sadržaj Pb bio signifikantno manji u AMF+ u usporedbi s AMF- tretmanom. Signifikantan učinak tretmana AMF+ na prinos, kvalitetu ploda (suha tvar, pH, ukupna kiselost, čvrstoća ploda), likopen i antioksidacijsku aktivnost je izostao. Temeljem dobivenih rezultata možemo zaključiti da je industrijska rajčica podložna nativnim AMF, dok je ciljana inokulacija presadnica AMF značajno povećala ukupni sadržaj fenola i P. Dobiveni rezultati ukazuju na potencijalnu primjenu AMF u komercijalnoj proizvodnji industrijske rajčice, međutim prethodna prilagodba uzgojnih uvjeta je neophodna za postizanje značajnijih rezultata.

The effects of different fertilisation treatments with arbuscular mycorrhizal fungi (AMF) inoculation on AMF root colonisation, fruit yield, nutrient and total phenol contents, volatile compound composition, and sensory attributes of tomato (Solanum lycopersicum L.) were investigated. Mineral, organic, and mineral + organic fertiliser application positively affected tomato yield (35%–50%) and phosphorus concentration (24%–29%) compared with controls. AMF application had a significant impact on the total nitrogen (+9%), manganese (+12%), and hydrophilic phenol (+8%) contents in the fruit. Volatile compounds were affected by the interactive effects of fertilisation and AMF application. The response of tomato fruit sensory quality indicators was relatively modest, with only a few sensory characteristics affected to a lesser extent. Although tomato showed susceptibility to field-native AMF, particular combinations of fertilisation and AMF inoculation were more effective at improving the quality parameters of tomatoes under field conditions applied in this study.

For two years, the tomatoes (cv. ‘Belle’ and ‘Clarabella’), ungrafted, self-grafted and grafted onto the ‘He-man’ rootstock, were grown under two irrigation regimes, i.e., partial-root zone drying (PRD) and fully irrigated (FI), to investigate whether grafting can alleviate drought stress and promote water-use efficiency (WUE). The grafted plants under the FI regime had the highest vegetative growth, which was the result of more leaves and greater leaf area and were only significantly different from the PRD grown ungrafted plants. The grafted plants had the highest yield as a result of the greater number of larger fruits and the yield did not differ between the irrigation treatments. No differences were found in the leaf NPK concentrations, while the Ca and Mg were higher under the PRD regime. The ungrafted plants under the PRD regime had the highest total soluble solids and acidity in the fruit juice. The grafted plants had a significantly higher WUE, more pronounced in the PRD regime. The different types of irrigation did not influence the vegetative growth and the yield in the greenhouse grown grafted tomato. The PRD and rootstock effects should be additionally investigated with deficit irrigation.

Reactions that occur when the plant is subjected to Citrus tristeza virus (CTV) infection often result in triggering numerous defence mechanisms to fight the infection. The reactions vary regarding virus strain, host genotype, time exposure to the infection and environmental conditions. No study has examined, to date and in detail, the consequence of ten-year exposure to CTV infection on biochemical and physiological status of susceptible Mexican lime plants (Citrus aurantifolia). To understand such kind of infection changes in nutrient status, total proteins, enzyme activity involved in scavenging stressed condition, photosynthetic and transpiration rates, chlorophyll content, membrane permeability and water content were analysed between different CTV strains and healthy plants. The activity of superoxide dismutase and polyphenol oxidase significantly decreased in the infected leaves, as well as membrane permeability which were lower in the infected plants. Macro- and micro-nutrient elements were significantly changed: concentrations of leaf nitrogen, zinc, magnesium and iron were elevated but potassium concentration depressed in relation to non-infected control leaves. No changes were found with other analysed nutrient elements, enzymes, photosynthesis and stomatal conductance, chlorophyll content and relative water content. As shown in this study clear physiological changes were found among infected and non-infected control plants but none between different CTV strains. Data suggests that some of the defence mechanism investigated here were supressed due to the continuous and long-term pressure of biotic stress. This article is protected by copyright. All rights reserved.

Food safety is one of the main concerns in the world and in wine it depends mostly on metabolites of microbial origin. The aim of this study was to investigate the occurrence of natural contaminants, ochratoxin A and biogenic amines (cadaverine, histamine, putrescine and tyramine), in Croatian commercial red wines originating from different Croatian wine-making regions. Ochratoxin A was detected in 92.8% of samples, however its concentrations in all samples were more than 10-fold lower than the limit set by the European Union (2 &micro, g/kg), marking these wines as safe for consumption. The frequency of occurrence and measured concentrations of ochratoxin A were higher in wines produced in southern regions with highest values obtained in wines from southern Dalmatian islands. All samples were contaminated with cadaverine and putrescine, while 88.2% and 82.7% were contaminated with histamine and tyramine, respectively. Histamine concentrations ranged from below the limit of detection to 8.5 mg/L. Higher histamine concentrations were measured in wines with higher pH values which coincided with southern geographic origin. These results reinforce the need for routine detection and quantification of biogenic amines in Croatian wines to achieve better control of vinification and minimize their formation.

The present study aimed to examine the effect of foliar (Mn_fol) and soil Zeolite-Mn (Mn_ZA) application on leaf mineral, total phenolic and oleuropein content, and mycorrhizae colonization of self-rooted cv. Leccino plantlets grown on calcareous soil. RESULTS The dissolution of zeolite was 97% when citric acid was applied at 0.05?mM?dm?3, suggesting that organic acids excreted by roots can dissolve modified zeolite (Mn_ZA), making Mn available for plant uptake. The leaf Mn concentration was the highest for Mn_fol treatment at 90 days after transplanting (DAT) (172?mg?kg?1) and 150 DAT (70?mg?kg?1) compared to other treatments. Mn_ZA soil application increased leaf Mn concentration at 150 DAT compared to control and NPK treatments. The oleuropein leaf content was highest for Mn_fol compared to other treatments at 90 DAT and lowest at 150 DAT. Arbuscular mycorrhizal colonization was higher for Mn_fol treatment at 150 DAT compared to all other treatments. CONCLUSION Changes in the arbuscular colonization percentage and oleuropein content may be connected to stress conditions provoked by a high leaf Mn concentration in the Mn_fol treatment at 90 DAT. Mn_ZA application increased leaf Mn concentration at 150 DAT compared to control and NPK treatments. It can be assumed that the dominant mechanism in Mn uptake from modified zeolite is Mn_ZA dissolution through root exudates. ? 2018 Society of Chemical Industry