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The aim was the evaluation of the biochemical and physiological responses of green- (GP) and red-leafed (RP) Prunus cerasifera mature leaves to 20 d of polyethylene glycol (PEG 6000)-induced water stress in order to elucidate a possible ameliorative role exerted by anthocyanins. At 10 d, the anthocyanin content remained unchanged in RP water-stressed leaves. Photosynthetic rate was lower in GP than that of RP (83.4 vs. 76.5%, respectively), paralleled by a higher degree of photoinhibition (Fv/Fm) in GP leaves. Leaves of GP accounted for higher content of soluble sugars at 10 d, when RP only showed a slight sucrose increase. At 20 d of stress, both morphs recovered their Fv/Fm values, suggesting the ability of both genotypes to adjust their photosynthetic metabolism under conditions of water stress. In conclusion, besides the sunscreen role served by anthocyanins, the carbon sink by these flavonoids might have further prevented sugar accumulation and the consequent sugar-promoted feedback regulation of photosynthesis in drought-stressed red leaves.

Trees play a pivotal role in the urban environment alleviating the negative impacts of urbanization, and for this reason, local governments have promoted strongly tree planting policies. However, poor soil quality and neglect tree maintenance (e.g., irrigation and fertilization) can seriously mine the plant health status during the tree establishment phase. The use of biochar to provide long-lasting C to the soil and, at the same time, improving soil properties (e.g., improved water holding capacity), soil enzymes activities and NPK concentrations, is a promising research field. Therefore, with a two-step experiment, the study aimed to assay the physiological responses of a commonly used urban tree species (Tilia × europaea L.) to 1.5 % (w/w) biochar amendment (B), and secondly, to assess the ability of trees, grown in biochar amended soil, to tolerate a period of drought. Biochar amendment increased P and K availability in the soil, resulting in higher P and K concentrations in B than control leaves, according to the leaf stage. This induced B trees, higher values in both total biomass than controls (+22 %) in well-watered plants. Moreover, the higher water availability in soil amended with biochar helped B trees to tolerate water stress, with better leaf photosynthetic performances and a faster recovery than stressed controls after the re-watering. This study highlights the dual function of the biochar, improving CO

Selected light wavebands promote plant development and/or the biosynthesis of targeted metabolites. This work offers new insights on the effects of red (R), green (G), blue (B), and white (W - R:G:B; 1:1:1) LED light supplementation on physiochemical traits of strawberry leaves. Gas exchange and chlorophyll fluorescence parameters, photosynthetic pigments, and superoxide anion (*O2-) content were analysed in plants grown for 1 (T1) and 17 (T17) d with light supplementations. At T1, light supplementations resulted in the enhancement of the de-epoxidation state of xanthophylls and nonphotochemical quenching, but no changes were observed in maximal photosynthetic rate (PNmax), irrespective of light spectra. At T17, xanthophyll contents remained higher only in R-supplemented plants. Overall, W light resulted in higher photosynthesis, whilst R and B light depressed PNmax values and promoted *O2- formation at T17. G light did not induce variations in photosynthetic traits nor induced oxidative stress at both T1 and T17.

The final stage of leaf ontogenesis is represented by senescence, a highly regulated process driven by a sequential cellular breakdown involving, as the first step, chloroplast dismantling with consequent reduction of photosynthetic efficiency. Different processes, such as pigment accumulation, could protect the vulnerable photosynthetic apparatus of senescent leaves. Although several studies have produced transcriptomic data on foliar senescence, just few works have attempted to explain differences in red and green leaves throughout ontogenesis. In this work, a transcriptomic approach was used on green and red leaves of Prunus cerasifera to unveil molecular differences from leaf maturity to senescence. Our analysis revealed a higher gene regulation in red leaves compared to green ones, during leaf transition. Most of the observed DEGs were shared and involved in transcription factor activities, senescing processes and cell wall remodelling. Significant differences were detected in cellular functions: genes related to photosystem I and II were highly down-regulated in the green genotype, whereas transcripts involved in flavonoid biosynthesis, such as UDP glucose-flavonoid-3-O-glucosyltransferase (UFGT) were exclusively up-regulated in red leaves. In addition, cellular functions involved in stress response (glutathione-S-transferase, Pathogen-Related) and sugar metabolism, such as three threalose-6-phosphate synthases, were activated in senescent red leaves. In conclusion, data suggests that P. cerasifera red genotypes can regulate a set of genes and molecular mechanisms that cope with senescence, promoting more advantages during leaf ontogenesis than compared to the green ones.

In the context of global warming, mild winter temperatures could compromise the fulfilment of the chilling requirement (CR) for overcoming flower bud endodormancy, impacting on the yields of perenn...

Current climate change negatively impacts on key seasonal biological processes of perennial plants causing erratic productions and, consequently, significant yield reductions. Being flowering time of fruit crops one of the most widely used indicators for climate change studies, the present research aimed to assess, over a long-term period (1973–2016), the climatic trend and its influence on blooming date and intensity of 40 apricot cultivars (Prunus armeniaca L.) grown in central Italy. Over the autumn-spring seasons, the main climatic parameters (temperature, rainfall) were acquired, and calculation of chill accumulation according to the Chilling Units model (CU) was performed. Results showed significant trends in warming of autumn-winter monthly minimum and average temperatures, particularly since the 1990s. During the critical period for overcoming of flower bud endodormancy, a dramatic loss of CUs was recorded. Most of the examined cultivars, belonging to Italian and foreign germplasm and opportunely selected for different flowering time, showed important blooming delays and blooming intensity decreases. In particular, the early-blooming cultivars showed the highest average shift of around 12 days and a loss in blooming intensity score which fell to levels of around 50% with respect to previous periods. The CUs, negatively correlated with blooming time and positively correlated with blooming intensity, seem to be crucial for apricot floral biology. The irregular autumn-winter cold rate of recent years may mean that substantial impacts can be expected in the future with possible geographic shifts of the apricot cultivation areas towards more potentially suitable areas located in the northern Italian and European regions, with considerable socioeconomic inference.

Global climate change represents a moving target for plant acclimation and/or adaptation, especially in the Mediterranean basin. In this study, the interactions of severe drought (20% of the effective daily evapotranspiration) and O3 fumigation (80 ppb, 5 h day−1, for 28 consecutive days) on (i) photosynthetic performance, (ii) cell membrane stability, (iii) hydric relations, (iv) accumulation of compatible solutes, and (v) lipophilic antioxidant compounds were investigated in young Quercus cerris plants. In addition to the typical drought-induced stomatal closure, imposition of water withholding dramatically influenced the profile of stress-associated metabolites, i.e., abscisic acid (ABA), proline, and lipophilic antioxidants. However, plants were not able to delay or prevent the negative effects of water deficit, the greatest impacting factor in this study. This translated into a steep decline of photosynthetic efficiency, leaf hydration, and membrane fluidity and permeability. When water stress was coupled with O3, plants orchestrated cross-talk among ABA, proline, and sugar in fully-expanded mature leaves, partially leading to a premature senescence.

A new frontier of nondestructive measurement exploitation is explored in this paper as concerns the food traceability and control arena. Presented is a method for nondestructive automated peach tree rootstock classification by means of high spectral resolution spectroscopy and multivariate signal processing. Many studies have shown that rootstock has significant impact on the quality and maturity of peach fruits. Rootstock knowledge not only enables fruit traceability but also helps in selecting the best storage condition and marketing channel. A novel automated method is presented to classify peach fruits with respect to their rootstock based on multivariate signal processing of fruit skin reflectance spectra, which are highly affected by physical and biochemical phenomena associated with fruit quality and maturity. The experimental results exploiting measurements of fruit skin reflectance spectra acquired in the visible and near infrared ranges with a high-resolution spectrometer show that automated rootstock classification by spectroscopic measurements and signal processing techniques is feasible and effective and has great potential in horticultural engineering.

Fresh-cut products (FCP) business has globally grown rapidly in the last decades. The success of FCP is mainly due to their practicality. Being them ready to eat, they perfectly meet the needed of people living in industrialized countries where the frenetic rhythms of life reduce the time devoted to food preparation. FCP also maintain high nutraceutical values, not too far from those of fresh fruits and vegetables. Cutting process negatively influences the shelf life of FCP and the many efforts concentrated to counteract the losses of product. Here, we summarize the strength and weakness of FCP and some new strategies to preserve them. Finally, some achievements of our research team are reported, especially those focused on the strategies to preserve the nutraceutical value of some FCP, and others intended to control the browning phenomenon with particular attention to the role of endogenous ascorbate as browning-preventing compound.

a b s t r a c t The concentrations of different metabolites in olive (Olea europaea (L.)) fruit at harvest can be affected by water availability, with significant consequences on the composition and the quality of the resulting oil. The aim of the present study was to profile the metabolic composition of ripe olives (cv. Cipressino) grown under water-stress and irrigated conditions applied during the last part of the fruit developmental cycle (from pit hardening to commercial harvest). The imposed conditions resulted in a moderate water stress (−3.5 MPa) at the end of the experimental period. Samples (pulp + skin) of fruit collected at the stage of complete epicarp pigmentation were analyzed by means of GC-MS. In total, 176 metabolites were detected, of which 57 were identified. Principal component analysis (PCA) of stress and non-stress treatments resulted in clearly separated profiles with the first principal component (PC1) mostly corre- lated with the organic acid content. Of the 57 compounds identified, 19 metabolites (organic acids, fatty acids, soluble sugars, and terpens) accumulated differently in the two sets of samples. A reduction in soluble sugars and unsaturated fatty acids was detected in water stressed samples, suggesting an accel- eration of the ripening process. These results highlighted the validity of metabolic profiling to study the effects of water stress in terms of both fruit composition and physiology.

Concerns about global warming led to the calculation of the carbon footprint (CF) left by human activities. The agricultural sector is a significant source of greenhouse gas (GHG) emissions, though cropland soils can also act as sinks. So far, most LCA studies on agricultural products have not considered changes in soil organic matter (SOM). This paper aimed to: (1) integrate the Henin–Dupuis SOM model into the CF study and (2) outline the impacts of different vineyard soil management scenarios on the overall CF. A representative wine chain in the Maremma Rural District, Tuscany (Italy), made up of a cooperative winery and nine of its associated farms, was selected to investigate the production of a non-aged, high-quality red wine. The system boundary was established from vineyard planting to waste management after use. The functional unit (FU) chosen for this study was a 0.75-L bottle of wine, and all data refer to the year 2009. The SOM balance, based on Henin–Dupuis’ equation, was integrated and run using GaBi4 software. A sensitivity analysis was performed, and four scenarios were developed to assess the impact of vineyard soil management types with decreasing levels of organic matter inputs. SOM accounting reduced the overall CF of one wine bottle from 0.663 to 0.531 kg CO2-eq/FU. The vineyard planting sub-phase produced a loss of SOM while, in the pre-production and production sub-phases, the loss/accumulation of SOM was related to the soil management practices. On average, soil management in the production sub-phase led to a net accumulation of SOM, and the overall vineyard phase was a sink of CO2. Residue incorporation and grassing were identified as the main factors affecting changes in SOM in vineyard soils. Our results showed that incorporating SOM accounting into the wine chain’s CF analysis changed the vineyard phase from a GHG source to a modest net GHG sink. These results highlighted the need to include soil C dynamics in the CF of the agricultural product. Here, the SOM balance method proposed was sensitive to changes in management practices and was site specific. Moreover, we were also able to define a minimum data set for SOM accounting. The EU recognises soil carbon sequestration as one of the major European strategies for mitigation. However, specific measures have yet to be included in the CAP 2020. It would be desirable to include soil in the new ISO 14067—Carbon Footprint of Products.

BACKGROUND: We investigated the effects of the foliar and fruit application of sodium selenate on selenium (Se) accumulation, fruit growth and ripening in peach and pear. Trials were conducted in two growing seasons. In 2008 selenate was applied at a rate of 0.1 and 1.0 mg Se L−1 to the leaves of peach. In 2009 selenate was applied at a rate of 1 mg Se L−1 via foliar (LT) or fruit (FT) application to peach and pear. RESULTS: The foliar addition of selenate to peach resulted in an increase in Se concentration both in leaves and fruit. The higher Se content in fruit resulted in an increase in flesh firmness and a decrease in soluble solid content. LT significantly increased the Se content in the leaves and fruit of peach and pear, and leaves showed the highest Se concentrations. FT increased the fruit Se concentration in both crops, and it was more effective than LT in increasing Se content. After storage, flesh firmness decreased in all treatments, but it was significantly higher in FT compared to LT and control samples. CONCLUSION: Foliar and fruit selenium spraying appeared effective in increasing the Se content of fruit in peach and pear. The enhanced Se concentration affected the shelf life of fruit, delaying the reduction in flesh firmness and fruit ripening, thus positively affecting fruit storage. Copyright © 2011 Society of Chemical Industry

In recent years, there has been an increasing interest from retailers, industries and environmental associations in estimating the life cycle of greenhouse gases emitted in the atmosphere from everyday products and services, also known as carbon footprint (CF). Life cycle assessment (LCA) is the most common methodology used to evaluate the environmental impact of a product. This approach was largely used in many industrial sectors and was also recently applied to quantify the environmental impact of the agri-food chain. Within agri-food products, wine is one of the most analysed, both for its importance in economic production and in the world distribution market. The present study is a part of the Carbon Label Project carried out in the wine production chain in the Maremma rural district (Tuscany, Italy). The project assesses the greenhouse gas (GHG) emissions from wine production for labelling purposes. Here, we evaluated the environmental performances of four high quality wines for carbon labelling. The international standards ISO 14040 and ISO 14044, and the Product Category Rules (PCR) Wine from Fresh Grapes (except sparkling wine) and Grape Must for the Environmental Product Declaration (EPD) certification, specifically for Climate Declaration, were used in order to carry out our analyses. The functional unit (FU) used here was one 0.75 L bottle of wine. The system boundaries were set from the vineyard planting to the distribution and waste disposal. The global warming potential (GWP) of four investigated wines was found to lie between 0.6 and 1.3 kg CO2-eq./bottle, showing a value comparable with literature. With all the four wines analysed, the agricultural phase covered, on average, 22% of the total GWP/bottle, while the main impact was in the production of the glass bottle. The results showed that the vineyard-planting phase has a significant impact on the wine CF, thus it has to be considered in the life cycle, while in literature it is frequently omitted. On the contrary, the pre-production phase did not present a relevant impact. The use of nitrogen fertilisers, the grapes’ yield and N2O emissions were the parameters that mostly affected the carbon footprint in the agricultural phase, as underlined by the sensitivity analysis.

A pot experiment was conducted with two Prunus genotypes (GF 677 and Mr.S.2/5, commercial rootstocks for peach), which are widely used in Italy and other European countries. Selenium (Se) was added as sodium selenate to 3-month-old micropropagated plants at a rate of 0 (control), 1.0, 2.5, and 5.0 mg Se (kg soil) -1 . Plant growth, gas exchange, and Se accumulation were studied. Selenium added at a rate of 2.5 and 5.0 mg Se kg -1 appeared to be highly toxic for the two young peach rootstocks. Thirty-three days after the treatment, the plants showed a high mortality rate. The fast growing rootstock, GF 677, appeared to be more sensitive to Se toxicity, the mortality rate reaching 52%. The higher the Se concentration in the soil, the higher it also was in the plant. In general, both genotypes were able to take up Se and to translocate high amounts from root to leaf. After selenate addition to the soil, both GF 677 and Mr.S.2/5 plants showed reduced plant growth with the highest Se treatments. Furthermore, Se induced a partial stomatal closure, as evidenced by the values of stomatal conductance, resulting in a reduction in net assimilation, and thus a decrease in dry-matter production. Selenate applied at a low rate (1 mg Se kg -1 ) stimulated plant growth in GF 677. One year after the Se treatment, a remobilization of Se from the storage organs to the young shoots was detected. This study demonstrates genotypic variation in Se uptake and accumulation in peach rootstocks.

Five different methods of determining sap flow (SF), three based on heat pulse (compensation heat pulse, New Zealand�cHP�NZ; compensation heat pulse, Greenspan/Australia�cHP�G (South oriented), and cHP�G�EW (East and West oriented, average); non-compensation heat pulse, Ariel/Israel�ncHP), one based on stem heat balance (Dynamax/USA�SHB), and another based on heat dissipation (Granier/France�HD) were compared in an experiment performed on peach trees in Northeast Spain. Two irrigation treatments (drip-irrigated) were applied: a control and a stress treatment, the latter consisting of withholding water from day 190 to 199. Between 1 and 3 different systems were installed in some trees of both, the control and stress treatments. All the techniques reflected the evolution of water stress in the stressed trees with a very similar tendency and in agreement with the evolution of predawn water potential (?p). ?p correlated well with sap flow (SF) determined with all the systems (r2 > 0.65) in the stress treatment, indicating that all the SF techniques detected changes in tree water status. The cHP�NZ system was the first to detect a SF reduction through the outer xylem vessels, as a response to water withholding. In control trees, daily SF rates provided by the three heat pulse and heat balance methods were well correlated with ETo and somewhat less with global radiation; all regressions improved on an hourly basis. Daily pattern and magnitude of mean SF rates monitored by the three heat pulse systems were quite similar in control trees. This was reflected by high regression coefficients when compared with each other. Higher SF rates recorded by ncHP methods in comparison with cHP�G and cHP�NZ might be attributed to technical limitations and to different sensor orientation. In an accompanying experiment, substantial differences between East and West location of the cHP�G sensors were observed, but when taking the mean value of those daily SF rates, differences between ncHP and cHP�G�EW were lower. Mean monthly crop coefficients, calculated by using SF data computed with ncHP method and soil evaporation as determined with microlysimeters, were 0.64 in July and 0.67 in August. SF systems can be used to detect plant water stress related to control, and might be useful for irrigation scheduling based on plant water status. The SF techniques analysed showed potential to better determine actual plant water necessities than other traditional methods, but a preceding calibration is needed

Summary Eleven peach cultivars (white- and yellow-flesh peaches, nectarines and canning clingstone peaches) were assayed for their antioxidant capacity and their content of some important organic compounds as well as vitamin C, carotenoids and phenols. Antioxidant capacity, determined by FRAP assay, varied between genotypes. Those with the highest value of Ferric Reducing Antioxidant Power (FRAP) were Federica and Springcrest. Antioxidant capacity was correlated to the amount of organic components with significant differences among the cultivars. In some case, antioxidant capacity was related to phenol content, as in yellow–flesh peaches. These results suggest the importance of genotype for determining antioxidant capacity, which, in turn, is related to the organic constituents, such as phenols, vitamin C and carotenoids.

In 2004 growing season, at the experimental vineyard of the DCDSL of the Pisa University, located at Colignola (Pisa, Italy), two grapevine genotypes, ‘Cabernet Sauvignon’ and ‘Sangiovese’, were subjected to different water treatments (irrigated and non irrigated) under field conditions. Time-course measurements of pre-dawn leaf water potential, as well as of both leaf gas exchange performance and net carbon gain were conducted. Changes in the content and composition of leaf polyphenols were also evaluated. Identification and quantification of hydroxycinnamates and flavonoid glycosides were performed using both HPLC-DAD and HPLC-MS analyses. We show that the share of newly assimilated carbon for the synthesis of phenylpropanoids increased because of moderate water deficit. The flavonoid to hydroxycinnamate ratio markedly increased passing from well-watered to drought-stressed plants, while the quercetin to kaempferol ratio slightly increased because of drought stress. We argue that the tested genotypes did not actually suffer from a severe oxidative damage under the attempt to impose a drought stress.

• Salt- and light-induced changes in morpho-anatomical, physiological and biochemical traits were analysed in Myrtus communis and Pistacia lentiscus with a view to explaining their ecological distribution in the Mediterranean basin. • In plants exposed to 20 or 100% solar radiation and supplied with 0 or 200 mM NaCl, measurements were conducted for ionic and water relations and photosynthetic performance, leaf morpho-anatomical and optical properties and tissuespecific accumulation of tannins and flavonoids. • Net carbon gain and photosystem II (PSII) efficiency decreased less in P. lentiscus than in M. communis when exposed to salinity stress, the former having a superior ability to use Na + and Cl – for osmotic djustment. Morpho-anatomical traits also allowed P. lentiscus to protect sensitive targets in the leaf from the combined action of salinity stress and high solar radiation to a greater degree than M. communis . Salt and light-induced increases in carbon allocated to polyphenols, particularly to flavonoids, were greater in M. communis than in P. Lentiscus, and appeared to be related to leaf oxidative damage. • Our data may conclusively explain the negligible distribution of M. communis in open Mediterranean areas suffering from salinity stress, and suggest a key antioxidant function of flavonoids in response to different stressful conditions.

Growth, gas exchange and water relations have been studied on hydroponically grown peach (cv. Armking) plants, grafted on GF677 (Arm/GF) and Mr.S.2/5 (Arm/MrS), exposed to 0, 40, 80 and 120 mM NaCl concentration, over a four-week period. Plant performance was also evaluated during a subsequent four-week period of relief from stress, by supplying the plants with a complete nutrient solution. Salinity stress reduced growth and net assimilation rate to a greater extent in Arm/GF than in Arm/MrS plants. Salt-induced water stress was more severe in Arm/GF than Arm/MrS leaves, and particularly during the first two weeks of treatment. On the other hand, leaf osmotic potential at full turgor (ΨπFT) of salt-treated Arm/MrS received a markedly greater contribution from Na+ and Cl− than salt-treated Arm/GF plants. By contrast, divalent cations and K+ made a substantially greater contribution to leaf ΨπFT of salt-treated Arm/GF than to the corresponding ΨπFT of Arm/MrS plants. Salinity stress markedly altered leaf carbohydrate composition and led to a preferential accumulation of sorbitol, independent on the scion/rootstock combination. Salt-treated Arm/GF but not Arm/MrS plants stored most of the Na+ and Cl− loaded in the shoot, into basal (old) leaves. The rootstock ability to control the accumulation of salt in the scion leaves during the salinity stress, determined striking differences in the recovery of photosynthetic performances, during the relief period. A full recovery of A and gs was detected in both 40 and 80 mM salt-treated Arm/GF leaves, but only in 40 mM salt-treated Arm/MrS, at the end of the relief treatment. These data indicate a greater efficiency of GF677 than Mr.S.2/5 in protecting peach plants from the deleterious effects of NaCl stress.

Three Prunus species, characterised by different levels of growth vigour, were used as rootstocks for peach [Prunus persica (L.) Batsch] grafting and compared for their hormone transport rates in the sap extracted from both the grafted scions and the ungrafted rootstocks. Two of these species were hybrid rootstocks widely used in peach orchards, while the third was a commercial cultivar, which was used both as rootstock and as scion. The xylem exudates were analysed for the concentrations of indoleacetic acid and for the main cytokinins, namely zeatin, zeatin riboside, isopentenyl-adenine and isopentenyl-adenosine. In ungrafted rootstocks the growth potential was positively correlated with both indoleacetic acid and zeatin riboside transport rates. In the xylem sap of peach scions grafted on the same rootstocks, the growth potential and the zeatin riboside levels were also positively correlated, while a negative correlation was found with indoleacetic acid levels. The results are discussed in view of the most widely accepted hypothesis concerning the control exerted by rootstocks on scion growth.

The behaviour of myrtle (Myrtus communis L.) plantlets during the last phase of in vitro culture before transplanting was studied. Myrtle plants were sampled from Mediterranean shrubland vegetation. In vitro growth of myrtle microcuttings was evaluated during the rooting phase using 500 cm3 containers fitted with two different types of closures. The number of gas exchanges and time in which aerated and closed vessels lose half of their gas content were calculated. Both types of vessel closure allowed photosynthetic activity in myrtle cultures even though the higher aeration rate induced higher net photosynthetic rate (PN) during all the culture. In vitro morphogenetic and rooting of myrtle microcuttings were affected by the different environment conditions inside the culture vessels: plantlet growth and root formation of myrtle explants increased in aerated vessels in comparison with closed ones. The well developed root system, the higher PN and dry mass accumulation during the pre-acclimatization phase in aerated vessels induced a better ability to face the transplant stress.