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Leaf water potential (LWP) is widely used to assess plant water status and it is commonly used by growers to make immediate crop and water management decisions. However, LWP measurement via direct method presents challenges as it is labour, time intensive and represents leaf-level conditions for sampling of small vineyard block. An alternative approach is using pigment concentration as a proxy for the canopy’s water status. Spectral data methods have been applied to monitor and evaluate crops’ biophysical variables. In this study, a model to predict LWP using via UAS equipped with a VIS-NIR multispectral camera and trained machine learning algorithm, is developed and tested. The model was tested on three dates in 2020 in a commercial vineyard in the Tufo Wine Region. Three modelling approaches (partial least square regression PLSR, support vector machine SVM, artificial neural network ANN) and two input datasets (combining spectral data and spectral vegetation indices) were used to estimate LWP. All approaches predicted LWP-based on spectral data classified from high to low; the results were consistent in direct proportion to the laboratory results and performed the best results. This research shows the potential for estimating LWP at a vineyard scale based on UAS information, represents a good and relatively cheap solution to assess plant status spatial distribution and therefore it could provide a direct way to achieve precise agricultural vineyard.

Currently, the main goal of agriculture is to promote the resilience of agricultural systems in a sustainable way through the improvement of use efficiency of farm resources, increasing crop yield and quality, under climate change conditions. This last is expected to drastically modify plant growth, with possible negative effects especially in arid and semi-arid regions of Europe on the viticultural sector. In this context, the monitoring of spatial behavior of grapevine during the growing season represents an opportunity to improve the plant management, winegrowers’ incomes, and to preserve the environmental health, but it has additional costs for the farmer. Nowadays UAS equipped with a VIS-NIR multispectral camera (blue, green, red, red-edge, and NIR) represents a good and relatively cheap solution to assess plant status spatial information (by means of a limited set of spectral vegetation indices), representing important support in precision agriculture management during the growing season. While differences between UAS-based multispectral imagery and point-based spectroscopy are well discussed in the literature, their impact on plant status estimation by vegetation indices is not completely investigated in depth. The aim of this study was to assess the performance level of UAS-based multispectral (5 bands across 450-800nm spectral region with a spatial resolution of 5cm) imagery, reconstructed high-resolution satellite (Sentinel-2A) multispectral imagery (13 bands across 400-2500 nm with a spatial resolution of Keywords: precision agriculture, vineyard monitoring, spectral measurements, CNN applied to viticulture, UAS.

In a soilless long-term salt-stress experiment, we tested the differences between the commercial sweet pepper cultivar “Quadrato d’Asti” and the landrace “Cazzone Giallo” in the structure and function of PSII through the JIP test analysis of the fast chlorophyll fluorescence transients (OKJIP). Salt stress inactivated the oxygen-evolving complex. Performance index detected the stress earlier than the maximum quantum yield of PSII, which remarkably decreased in the long term. The detrimental effects of salinity on the oxygen evolving-complex, the trapping of light energy in PSII, and delivering in the electron transport chain occurred earlier and more in the landrace than the cultivar. Performance indexes decreased earlier than the maximum quantum yield of PSII. Stress-induced inactivation of PSII reaction centers reached 22% in the cultivar and 45% in the landrace. The resulted heat dissipation had the trade-off of a correspondent reduced energy flow per sample leaf area, thus an impaired potential carbon fixation. These results corroborate the reported higher tolerance to salt stress of the commercial cultivar than the landrace in terms of yield. PSII was more affected than PSI, which functionality recovered in the late of trial, especially in the cultivar, possibly due to heat dissipation mechanisms. This study gives valuable information for breeding programs aiming to improve tolerance in salt stress sensitive sweet pepper genotypes.

Currently, the main goal of agriculture is to promote the resilience of agricultural systems in a sustainable way through the improvement of use efficiency of farm resources, increasing crop yield and quality, under climate change conditions. Climate change is one of the major challenges for high incomes crops, as the vineyards for high-quality wines, since it is expected to drastically modify plant growth, with possible negative effects especially in arid and semi-arid regions of Europe. In this context, the reduction of negative environmental impacts of intensive agriculture (e.g. soil degradation), can be realized by means of high spatial and temporal resolution of field crop monitoring, aiming to manage the local spatial variability.The monitoring of spatial behaviour of plants during the growing season represents an opportunity to improve the plant management, the farmer incomes and to preserve the environmental health, but it represents an additional cost for the farmer.The UAS-based imagery might provide detailed and accurate information across visible and near infrared spectral regions to support monitoring (crucial for precision agriculture) with limitation in bands and then on spectral vegetation indices (Vis) provided. VIs are a well-known and widely used method for crop state estimation. The ability to monitor crop state by such indices is an important tool for agricultural management. While differences in imagery and point-based spectroscopy are obvious, their impact on crop state estimation by VIs is not well-studied. The aim of this study was to assess the performance level of the selected VIs calculated from reconstructed high-resolution satellite (Sentinel-2A) multispectral imagery (13 bands across 400-2500nm with spatial resolution of The test site is a portion of vineyard placed in southern Italy cultivated on Greco cultivar, in which the soil-plant and atmosphere system has been monitored during the 2020 vintage also through ecophysiological analyses. The data analysis will follow the methodology presented in a recently published paper (Polinova et al., 2018).The study will connect the method and scale of spectral data collection with in vivo plant monitoring and prove that it has a significant impact on the vegetation state estimation results. It should be noted that each spectral data source has its advantages and drawbacks. The plant parameter of interest should determine not only the VIs type suitable for analysis but also the method of data collection.The contribution has been realized within the CNR BIO-ECO project.

Salt stress is one of the most impactful abiotic stresses that plants must cope with. Plants&rsquo, ability to tolerate salt stress relies on multiple mechanisms, which are associated with biomass and yield reductions. Sweet pepper is a salt-sensitive crop that in Mediterranean regions can be exposed to salt build-up in the root zone due to irrigation. Understanding the physiological mechanisms that plants activate to adapt to soil salinization is essential to develop breeding programs and agricultural practices that counteract this phenomenon and ultimately minimize yield reductions. With this aim, the physiological and productive performances of Quadrato D&rsquo, Asti, a common commercial sweet pepper cultivar in Italy, and Cazzone Giallo, a landrace of the Campania region (Italy), were compared under different salt stress treatments. Quadrato D&rsquo, Asti had higher tolerance to salt stress when compared to Cazzone Giallo in terms of yield, which was associated with higher leaf biomass vs. fruit ratio in the former. Ion accumulation and profiling between the two genoptypes revealed that Quadrato D&rsquo, Asti was more efficient at excluding chloride from green tissues, allowing the maintenance of photosystem functionality under stress. In contrast, Cazzone Giallo seemed to compartmentalize most sodium in the stem. While sodium accumulation in the stems has been shown to protect shoots from sodium toxicity, in pepper and/or in the specific experimental conditions imposed, this strategy was less efficient than chloride exclusion for salt stress tolerance.

Mediterranean tomato landraces adapted to arid environments represent an option to counteract drought, and to address the complexity of responses to water deficit and recovery, which is a crucial component of plant adaptation mechanisms. We investigated physiological, biochemical and molecular responses of two Mediterranean tomato landraces, "Locale di Salina" (Lc) and "Pizzutello di Sciacca" (Pz) under two dehydration periods and intermediate rehydration in greenhouse pot-experiments. Relationship between CO2 assimilation and stomatal conductance under severe water stress (gs < 0.05 mol m-2 s-1 ) indicated the occurrence of stomatal and non-stomatal limitations of photosynthesis. Gas-exchanges promptly recovered within 2-3-day re-hydration. ABA and gs showed a strict exponential relationship. Both leaf ABA and proline peaked under severe water stress. Lc showed higher accumulation of ABA and higher induction of the expression of both NCED and P5CS genes than Pz. PARP increased during imposition of stress, mainly in Lc, and decreased under severe water stress. The two landraces hardly differed in their physiological performance. Under severe water stress, stomatal conductance showed low sensitivity to ABA, which instead controlled stomatal closure under moderate water stress (gs > 0.15 mol m-2 s-1 ). The prompt recovery after re-dehydration of both landraces confirmed their drought tolerant behaviour. Differences between the two landraces were instead observed at biochemical and molecular levels. This article is protected by copyright. All rights reserved.

The soil salinity increase in the Mediterranean basin is one of the consequences of the climate change. The aim of this study was to evaluate the adaptability of giant reed (Arundo donax L.) to salinity, in conditions of higher temperatures, in order to hypothesise the future use of giant reed under these conditions. The trial was carried out in pots under a permanent metal structure, open on the sides and with a clear PE on the top. Four levels of soil salinity in the range 3.3-15.5 dS m–1 were imposed. The stem number of the most stressed treatment was about 45% lower than the control and also the stem height was lower than in all other treatments. The green and yellow leaf number decreased as the soil salinity increased, and their sum was significantly lower in the two most stressed treatments. Osmotic potential of the leaf sap was not affected by salinity. Leaf water potential and stomatal conduc- conductance in the saline treatments were lower than in the control. tance Assimilation rate showed similar pattern of stomatal conductance. Intrinsic WUE remained almost stable until July and increased during August under the most stressful conditions. PSII photochemistry was not affected by soil salinity. Biomass yield was not different from the control until to soil ECe 12.0 dS m–1: only the most stressed treatment (15.5 dS m–1) caused yield losses (50%). Tolerance threshold to salinity was 11.2 dS m–1 and the relative yield losses were 11.6% per dS m–1.

Trichoderma spp. are beneficial soil microorganisms used in sustainable agriculture for their ability to enhance plant performance under different environments. However, Trichoderma-activated mechanisms that help plants to cope with water stress are still not completely defined. We investigated morpho-physiological, biochemical and transcriptomic responses to PEG-induced short severe water stress in Trichoderma longibrachiatum-inoculated and non-inoculated Solanum lycopersicum. Trichoderma had significant biostimulation effects on the plant and, after stress, allowed recovery of growth and photosynthesis to the levels of unstressed plants. Whole-transcriptome analysis was carried out after 1 day of 15 % PEG treatment in 22-day Trichoderma-inoculated and non-inoculated plants. Under non-stress conditions, Trichoderma triggered an extensive transcriptional reprogramming, specifically modulating the expression of classes of transcription factors and of genes involved in photosynthesis, antioxidant defences and maintenance of a juvenile state. Though the effects of water stress were predominant, mainly boosting transcription of stress-responsive genes, pre-treatment with Trichoderma specifically affected genes involved in mitigation of stress damage. Our findings provide new insights into the plant interplay with Trichoderma, useful to further exploit rhizosphere fungi for the improvement of plant performance under limiting environments.

Water deficit limiting yields is one of the negative aspects of climate change. However, this applies particularly when emphasis is on biomass production (e.g. for field crops), but not necessarily for plants where quality, not quantity is most relevant. For grapevine development, mild water stress occurring during specific phenological phases is an important factor when producing good quality wines. It induces the production of anthocyanins and aroma precursors and then could offer an opportunity to increase winegrower's income. A multidisciplinary study was carried out in Campania region (Southern Italy), an area well known for high quality wine production. Growth of Aglianico grapevine cultivar, with a standard clone population on 1103 Paulsen rootstocks, was studied on two different types of soil: Calcisols and Cambisols occurring along a slope of 90 m length with 11% gradient. The agro-hydrological model SWAP was calibrated and applied to estimate soil-plant water status during three consecutive seasons (2011–2013). Crop water stress index (CWSI), as estimated by the model, was related to leaf water potential, sugar content of grape bunches and wine quality (e.g. content of tannins). For both soils, the correlations between quality measurements and CWSI were high (e.g. − 0.97** with sugar; 0.895* with anthocyanins in the grape skins). The model was also applied to explore effects of future climate conditions (2021–2051) obtained from statistical downscaling of Global Circulation Models (AOGCM) and to estimate the effect of the climate on CWSI and hence on grape quality. Effects of climate change on grape quality indicate: (i) a resilient behavior of Calcisol to produce high quality wine, (ii) a good potentiality for improving the quality wine in Cambisol. The present study represents an example of multidisciplinary approach in which soil scientists, hydro-pedologists, crop modellers, plant physiologists and oenologists have integrated their knowledge and skills in order to deal with the complex interactions among different components of an agricultural system.

Grapevine is well adapted to Mediterranean climate where it is commonly cultivated along the slopes in hilly areas. The soil is a primary factor of terroir. Soils with limited water holding capacity can bring to vine water stress, which affects grape and wine quality. Along the slope, heterogeneity of soil physical properties and water flow can allow better soil water status in down- than up-hill soil. In the literature, discrimination between these two factors is often only qualitatively addressed and differences in grape and wine quality between down- and up-hill soil are often attributed to a generic "slope effect". Our aim is to discriminate in a vineyard grown along slopes, the role played by the hydraulic properties from the topographic characteristics in producing differences in soil water availability and therefore differences in grapevine water status, which, in turn, affects physiological responses, growth, yield and grape/wine quality. The experimental site was an "Aglianico" vineyard grown along a 90 m slope (17.7 %) in a hilly area of the Mediterranean environment. The two soil sites, Cambic Calcisol (Up-hill) and Eutric Cambisol (Down-hill), had similar clay loam texture with different hydrological properties. Soil and vine water status, leaf gas exchanges and fluorescence, leaf area index, yield, and grape and wine quality were measured in the up- and down-hill side of the slope in two consecutive years. Hydrus-2D model was used to simulate water flow along the slope to estimate water status in the soil-plant-atmosphere continuum by using the two-year climate data set. We compared the model outputs for the two soil sites with the field experimental measurements. Finally, in order to quantify the effect of the slope steepness on the soil water balance of the two soils, the model was applied to simulate water flow with and without slope. Down-hill soil had higher both soil matric potential and water content than Up-hill soil. Vines at bottom of slope had better leaf water status and higher gas-exchanges rate, photosynthetic efficiency, leaf area index and grape yield than vines at the top. On the contrary, quality of both grape and wine were enhanced in the more stressed uphill than down-hill vines. Along the two years, Hydrus-2D simulations showed higher soil water availability in the Down- than the Up-hill soil. This result was predominantly caused by the different hydraulic properties between the two site soils, whereas the estimated contribution of both superficial runoff and lateral infiltration (inside soil) along the slope was negligible. In conclusion, the "slope effect" on the soil water status and consequently on the vineyard behaviour, was mainly dominated by soil hydraulic properties rather than the steepness of the slope.

Cereals production is becoming a challenge in the Agriculture of the Bekaa valley in Lebanon. Lack of water is the driving force of agricultural research which is mainly focused on introduction of drought resistant cultivars, application of conservation tillage and supplemental irrigation. In this context, within of ACLIMAS demonstration project within the Sustainable Water Integrated Management Program (SWIM) of the European Commission, a field experiment on barley and durum wheat crop responses to different treatments (conservative and conservation soil tillage and supplemental irrigation) was realized. Forty-eight experimental plots were laid out for three years in a statistical split plot design. The statistical analyses showed that aboveground biomass and yield were significantly affected by supplemental irrigation for barley but not for the yield of durum wheat. A soil survey indicated that the implicit assumption of soil homogeneity of the agronomic design was correct for soil surface soil but that two different soil types (Cambisols and Fluvisols) had to be distinguished considering subsoil conditions and corresponding rooting patterns. Then, a simulation modelling analysis on crop responses under climate change, considering the soil spatial heterogeneity was done. This last by means the use of the simulation model SWAP, validated for local conditions using measurements of soil water contents, aboveground biomass and yield of wheat. The validated model was applied to estimate yields focusing on the application of supplemental irrigation. Yields for "Mikii3" a durum wheat cultivar are expected to increase by 14% in both soils due to climate change. More importantly, only 3 supplemental irrigations would be needed for the deep soil requiring 5% more water as compared with current climate trend, while the shallow soil needs 35% more water.

This paper aims to test a new physically oriented approach to viticulture zoning at farm scale that is strongly rooted in hydropedology and aims to achieve a better use of environmental features with respect to plant requirements and wine production. The physics of our approach are defined by the use of soil–plant–atmosphere simulation models, applying physically based equations to describe the soil hydrological processes and solve soil–plant water status. This study (part of the ZOVISA project) was conducted on a farm devoted to production of high-quality wines (Aglianico DOC), located in southern Italy (Campania region, Mirabella Eclano, AV). The soil spatial distribution was obtained after standard soil survey informed by geophysical survey. Two homogeneous zones (HZs) were identified; in each one a physically based model was applied to solve the soil water balance and estimate the soil functional behaviour (crop water stress index, CWSI) defining the functional homogeneous zones (fHZs). For the second process, experimental plots were established and monitored for investigating soil–plant water status, crop development (biometric and physiological parameters) and daily climate variables (temperature, solar radiation, rainfall, wind). The effects of crop water status on crop response over must and wine quality were then evaluated in the fHZs. This was performed by comparing crop water stress with (i) crop physiological measurement (leaf gas exchange, chlorophyll a fluorescence, leaf water potential, chlorophyll content, leaf area index (LAI) measurement), (ii) grape bunches measurements (berry weight, sugar content, titratable acidity, etc.) and (iii) wine quality (aromatic response). This experiment proved the usefulness of the physically based approach, also in the case of mapping viticulture microzoning.

Given its high biomass and plasticity, Arundo donax L. is a promising ligno-cellulosic crop for cultivation in marginal lands in temperate climates. In order to test for adaptation to salinity, growth parameters of several A. donax clones were evaluated under two salt regimes in hydroponics. Mild NaCl stress (50 mM NaCl, 5.6 mS cm−1 EC, for 10 days) failed to discriminate between ecotypes, while a more severe NaCl treatment (150 mM, 18.8 mS cm−1 EC, for 21 days) enabled the identification of ecotypes maintaining plant growth under high salinity. Among several biometric parameters, 4th leaf width, and shoot and root DW consistently highlighted differences between ecotypes. Gas-exchange parameters also responded to severe NaCl treatment, while the photosystem efficiency was good, regardless of treatment. The results confirm that A. donax can be considered moderately tolerant to NaCl stress, with variation between ecotypes. Our screening protocol identified ecotypes with higher biomass production under severe NaCl treatment and can be useful for preliminary evaluation of NaCl tolerant clones for increasing productivity under salinity. The detected inter-ecotype variability could also be investigated to identify suitable clones for different environments.

Maintaining cereal production in the Bekaa valley in Lebanon presents a serious challenge. Lack of water is the driving force of agricultural research which is mainly focused on introduction of drought resistant cultivars, application of conservation tillage and supplemental irrigation. In this context forty-eight experimental plots were laid out for three years in a statistical split plot design. The statistical analyses showed that aboveground biomass and yield were significantly affected by irrigation for barley but not for the yield of durum wheat. Effects of soil tillage practices and introduction of new cultivares were not significant. A soil survey indicated that the implicit assumption of soil homogeneity of the agronomic design was correct for surface soil but that two different soil types (Cambisols and Fluvisols) had to be distinguished considering subsoil conditions and corresponding rooting patterns. Therefore, the main objective of this paper was to determine the effects of different soil types on crop response and, in addition, to assess how physically-based modeling can predict future effects of climate change on crops and soils. Simulation model SWAP was validated for local conditions using measurements of soil water contents, aboveground biomass and yield of wheat. Considering two rather than one soil type for the experimental area resulted in different conclusions for both crops as to the effectivity of both conservation tillage and irrigation, demonstrating that a distinction of only one soil type results in misleading results. The validated model was applied to estimate yields considering climate change, focusing on the application of supplemental irrigation. Yields for “Mikii3” a durum wheat cultivar are expected to increase by appr. 14% in both soils due to climate change. More importantly, only 3 supplemental irrigations would be needed for the deep soil requiring 5% more water as compared with current climate trend, while the shallow soil needs 13 irrigations, corresponding with a need for 35% more water. This is highly significant from an economic point of view and supports the relevance of distinguishing two soil types. It was demonstrated the synergy of joint research by the agronomic and soil science community and the need for executing a soil survey in future when planning agronomic experiments, including a hydrological soil characterisation.

Tomato is a major crop in the Mediterranean basin, where the cultivation in the open field is often vulnerable to drought. In order to adapt and survive to naturally occurring cycles of drought stress and recovery, plants employ a coordinated array of physiological, biochemical, and molecular responses. Transcriptomic studies on tomato responses to drought and subsequent recovery are few in number. As the search for novel traits to improve the genetic tolerance to drought increases, a better understanding of these responses is required. To address this need we designed a study in which we induced two cycles of prolonged drought stress and a single recovery by rewatering in tomato. In order to dissect the complexity of plant responses to drought, we analyzed the physiological responses (stomatal conductance, CO2 assimilation, and chlorophyll fluorescence), abscisic acid (ABA), and proline contents. In addition to the physiological and metabolite assays, we generated transcriptomes for multiple points during the stress and recovery cycles. Cluster analysis of differentially expressed genes (DEGs) between the conditions has revealed potential novel components in stress response. The observed reduction in leaf gas exchanges and efficiency of the photosystem PSII was concomitant with a general down-regulation of genes belonging to the photosynthesis, light harvesting, and photosystem I and II category induced by drought stress. Gene ontology (GO) categories such as cell proliferation and cell cycle were also significantly enriched in the down-regulated fraction of genes upon drought stress, which may contribute to explain the observed growth reduction. Several histone variants were also repressed during drought stress, indicating that chromatin associated processes are also affected by drought. As expected, ABA accumulated after prolonged water deficit, driving the observed enrichment of stress related GOs in the up-regulated gene fractions, which included transcripts putatively involved in stomatal movements. This transcriptomic study has yielded promising candidate genes that merit further functional studies to confirm their involvement in drought tolerance and recovery. Together, our results contribute to a better understanding of the coordinated responses taking place under drought stress and recovery in adult plants of tomato.

Non-photochemical quenching (NPQ) of chlorophyll a fluorescence and leaf gas-exchange were investigated in relation to the chlorophyll and carotenoid content, and the xanthophyll cycles in wild type tomato (Solanum lycopersicum, L. cv Red Setter (RS)) and in two transgenic lines (UO and UU) over-expressing β-carotene hydroxylase. Potted plants were grown in a glasshouse under low light (LL, 100 μmol m−2 s−1) or high light (HL, 300 μmol m−2 s−1). The maximum quantum efficiency of photosystems II (PSII) photochemistry in dark-adapted leaves (Fv/Fm) was higher than 0.82 in all treatments while photosynthetic CO2 assimilation (A) was higher than 14 μmol m−2 s−1, and stomatal conductance (gs) higher than 0.4 mol m−2 s−1 in HL plants, indicating no effects induced by the genetic modification. Chlorophyll content and composition changed little, whereas transgenic plants had up to 47% higher total carotenoid content than wild type plants. Violaxanthin was the most abundant carotenoid in transgenic plants, with more than 2-fold higher content than the average 0.586 mg g−1 found in RS plants. Transgenic plants had similar light-induced steady-state NPQ compared to wild type plants, but had slower dark relaxation because of the decreased de-epoxydation state index due to the higher violaxanthin accumulation, despite the higher zeaxanthin content.

The eco-physiology of 'Falanghina' grapevine was studied in Telesina valley (Southern Italy) in two nearby vineyards. The soil was characterised by a higher, site 1 (T1) and a lower, site 2 (T2), water availability. Soil water content, leaf water status and gas-exchanges were monitored during summer 2004 and showed that in the T1 and T2 the vines were subjected to different degree of water stress as soil moisture was depleted. Midday leaf water potential decreased in summer compared with spring but remained quite stable during summer, suggesting a nearly isohydric behaviour for this cultivar, with no appreciable difference between the two sites. Conversely to leaf water potential, stomatal conductance to water vapour strongly decreased during summer and at beginning of August showed quite higher values (0.204 mol m-2s-1) in the T1 compared with T2 (0.065 mol m-2s-1). The response of grapevine to water deficit was the closure of stomata and not a noticeable decrease in leaf water potential. Compared with stomatal conductance, CO2 assimilation showed a lower sensitivity to soil water deficit, resulting in a decrease of intrinsic water use efficiency during occurrence of stressful conditions of summer. This information can be useful to understand the relationships between soil characteristics, water relations and grape quality. INTRODUCTION

This paper aims to test a new physically oriented approach to viticulture zoning at the farm scale, strongly rooted on hydropedology and aiming to achieve a better use of environmental features with respect to plant requirement and wine production. The physics of our approach is defined by the use of soil-plant-atmosphere simulation models which applies physically-based equations to describe the soil hydrological processes and solves soil-plant water status. This study (ZOVISA project) was conducted in a farm devoted to high quality wines production (Aglianico DOC), located in South Italy (Campania region, Mirabella Eclano-AV). The soil spatial distribution was obtained after standard soil survey informed by geophysical survey. Two Homogenous Zones (HZs) were identified; in each one of those a physically based model was applied to solve the soil water balance and estimate the soil functional behaviour (crop water stress index, CWSI) defining the functional Homogeneous Zones (fHzs). In these last, experimental plots were established and monitored for investigating soil-plant water status, crop development (biometric and physiological parameters) and daily climate variables (temperature, solar radiation, rainfall, wind). The effects of crop water status on crop response over must and wine quality were then evaluated in the fHZs. This was performed by comparing crop water stress with (i) crop physiological measurement (leaf gas exchange, chlorophyll a fluorescence, leaf water potential, chlorophyll content, LAI measurement), (ii) grape bunches measurements (berry weight, sugar content, titratable acidity, etc.) and (iii) wine quality (aromatic response). Eventually this experiment has proved the usefulness of the physical based approach also in the case of mapping viticulture microzoning.

The use of the compensation heat-pulse velocity (CHPV) technique to estimate sap flow in olive trees as a means of irrigation scheduling can be a difficult task because of the naturally heterogeneity of hydraulic functioning of sapwood area in this species. As a result, the monitoring of an unreasonably large number of both trees and CHPV gauges per tree is needed for accurate estimation of orchard transpiration. The approach used in this paper restricts the monitoring of a large number of both trees and gauges to a very short time (a day) and allows the long term estimation of transpiration of several olive trees by the continuous monitoring of a sole CHPV gauge installed in a single tree. In an experimental olive orchard in southern Italy, we monitored six CHPV gauges in three well irrigated trees (treatment T100) and six CHPV gauges in three rain-fed trees (treatment T0) at half hour intervals for 60 days during summer 1999. For each ith gauge at each day, we linearly regressed the sap flow (Qi, l h−1) against the mean sap flow of the all other n−1 gauges of the same treatment (Qmi). The regression parameters were used to obtain an estimation of Qmi (EQmi) throughout the trial using the data of any single ith gauge. In order to test the prediction power of the model of ith gauge, the estimated mean sap flow (EQmi) values were regressed day by day against the actually measured Qmi. The same procedure was also applied at the time scale of a day, that is to the daily cumulative value of Qi and Qmi. In all cases, we obtained high statistical significance of the models applied to data as confirmed by the high adjusted R2 estimates. Our analyses show the feasibility of estimating the transpiration rate of many trees by monitoring sap flow in a single tree by the use of a sole CHPV gauge. The results of this work indicate that CHPV can be a useful and powerful method for irrigation scheduling for olive and other tree species.

The terroir analysis, aiming to achieve a better use of environmental features with respect to plant requirement and wine production, needs to be strongly rooted on hydropedology. In fact, the relations between wine quality and soil moisture regime during the cropping season is well established. The ZOViSA Project (Viticultural zoning at farm scale) tests a new physically oriented approach to terroir analysis based on the relations between the soil-plant water status and wine quality. The project is conducted in southern Italy in the farm Quintodecimo of Mirabella Eclano (AV) located in the Campania region, devoted to quality Aglianico red wine production (DOC). The soil spatial distribution of study area (about 3 ha) was recognized by classical soil survey and geophysics scan by EM38DD; then the soil-plant water status was monitored for three years in two experimental plots from two different soils (Cambisol and Calcisol). Daily climate variables (temperature, solar radiation, rainfall, wind), daily soil water variables (through TDR probes and tensiometers), crop development (biometric and physiological parameters), and grape must and wine quality were monitored. The agro-hydrological model SWAP was calibrated and applied in the two experimental plots to estimate soil-plant water status in different crop phenological stages. The effects of crop water status on crop response and wine quality was evaluated in two different pedo-systems, comparing the crop water stress index with both: crop physiological measurements (leaf gas exchange, leaf water potential, chlorophyll content, LAI measurement), grape bunches measurements (berry weight, sugar content, titratable acidity, etc.) and wine quality (aromatic response). Finally a "spatial application" of the model was carried out and different terroirs defined.

The need for contrasting soil degradation while improving crop quality and productivity in the light of climate change has attracted considerable attention on the utilisation of rhizosphere microorganisms as bio-stimulants, which could contribute to convert conventional agricultural practices to environmentally sustainable management of crops. To this end, soil fungi belonging to the Trichoderma genus appear very promising since they are known to be efficient "plant growth promoters" and recent data indicate they could also improve plant resistance to water deficit, at least in part by enhancing the antioxidant machinery. However, the mechanisms by which they exert this effect need extensive characterisation. The model system of the facultative symbiosis between Solanum lycopersicum L. and T. longibrachiatum was therefore chosen to study the contribution of beneficial soil microorganisms to plant stress tolerance. In fact, the availability of advanced genomic platforms for both the plant and the microbe counterparts hold promises to allow a better understanding of the plant response to beneficial microorganisms and dissection of the complexity of the molecular events occurring in tomato in response to water stress. A hydroponic floating system was specifically designed which allowed interaction between tomato plants cv "Crovarese" and T. longibrachiatum strain MK1 to occur. Water deficiency was mimicked in three-week-old plants treated (T) and not treated (control, Ctrl) with T. longibrachiatum MK1 by adding 15% polyethylene glycol (PEG) to the growing nutrient medium for 24, 48 and 72 h, followed by a recovery phase of 7 d in fresh medium without PEG. Large-scale transcriptomic data were produced from control (Ctrl), MK1-treated (T), PEG-treated (P) and MK1+PEG-treated (T+P) tomato leaves by a directional single-end sequencing with Illumina HiSeq1500. Biometric and physiological analyses confirmed the positive effects of MK1 on growth promotion of tomato plants. As expected, PCA analysis of transcriptomic data suggests that the PEG treatment is the major cause of difference between the samples. When the fold change threshold was set to 1.1 (log2 scale), PEG was found to modify transcription of 2749 genes in respect to Ctrl (1584 up-regulated and 1165 down-regulated), while 1174 genes (540 up-regulated and 634 down-regulated) responded to MK1 As a whole, biometric, physiological and transcriptomic data indicate significant effects of MK1 on tomato response to water deficit that will be discussed in detail. This work was partly supported by the Project GenoPOM-pro PON02_00395_3082360 of the Italian Ministry of Education, University and Scientific Research (MIUR).

The use of black leaf-clips for dark adaptation under high solar radiation conditions is reported to underestimate the maximum quantum yield of PSII photochemistry (F-v/F-m) measured by the continuous-excitation fluorometer Pocket PEA. The decrease in F-v/F-m was due to a rise in minimum fluorescence emission (F-o), probably resulting from increased leaf temperature (T-l). In field-grown tomato and pepper, fluorescence parameters and T-l in the region covered by the black leaf clip were measured in clipped leaves exposed to solar radiation during dark adaptation (clipped-only leaves) and in clipped leaves protected from solar radiation by aluminium foil (shrouded clipped leaves). Results confirmed significant F-v/F-m underestimates in clipped-only leaves primarily due to increased F-o. In one tomato experiment, T-l increased from 30 to 44.5A degrees C in clipped-only leaves, with a negligible rise in shrouded clipped leaves. In two respective pepper experiments, T-l in clipped-only leaves increased from 27 to 36.2A degrees C and 33 to 40.9A degrees C. Based on the results of this study, a clip-effect parameter (P-CE) on fluorescence emission is proposed as the difference for F-v/F-m (or -F-o/F-m) between shrouded clipped leaves and clipped-only leaves, which resulted to be 0.706 for tomato, and 0.241 and 0.358 for the two pepper experiments.

The ZOViSA Project (Viticultural zoning at farm scale) tests a new physically oriented approach to terroir analysis, strongly rooted on hydropedology and aiming to achieve a better use of environmental features with respect to plant requirement and wine production. The physics of our approach is defined by the use of soil-plant-atmosphere simulation models which apply physically-based equations to describe the soil hydrological processes and solve soil-plant water status. The project is conducted in two farms of southern Italy (Del Monte-Ponte(BN) and Quintodecimo-Mirabella Eclano (AV)) located in the Campania region and devoted to quality wines production (Aglianico and Falanghina DOC). In one site (Quintodecimo farm) the soil spatial distribution was recognized; then the soil-plant water status was monitored in two experimental plots from two different soils. Daily soil water variables (through TDR probes and tensiometers), crop development (biometric and physiological parameters) and daily climate variables (temperature, solar radiation, rainfall, wind) were monitored. The SWAP model was calibrated and applied in the two experimental plots to estimate soil-plant water status in different crop phenological stages. The effects of crop water status on crop response and wine quality was evaluated in two different pedo-systems, comparing the crop water stress index with both: crop physiological measurement (leaf gas exchange, chlorophyll-a fluorescence, leaf water potential, chlorophyll content, LAI measurement), grape bounches measurement (berry weight, sugar content, titrable acidity, etc.) and wine quality (aromatic response). Finally a preliminary "spatial application" of the model was carried out and different terroirs defined.

The aim of the work is to describe for two different coastal pedo-climatic areas of Southern Italy and one area in NW China the effects that saline water and drought have had on the soil physical properties. On these soils the observed changes in soil physical properties after long-term salt accumulation will be reported. The observed differences in soil hydrological properties of saline soils may have a significant impact on the temporal variability of soil water content, e.g. on frequency and duration of soil water content lower than a pre-defined critical threshold. To this end the soil water balance calculations will be performed for a range of different meteorological conditions, in particular when a dry, wet and normal climatic year occurs. To do that the SWAP numerical model (vers 2.0.7d) has been used. The water balance calculations will be used to evaluate the water storage in the profile through the year. At Torre Lama the h(?) curve of the 1% saline water treatments had lower values of ? than the 0% treatments at the same pressure head. Different behaviour was observed for Vitulazio, the total porosity for the I0 treatment is around 0.55 against 0.58 of the I1 treatment, in contrast with what observed for the Torre Lama site. Such difference could depend from the shorter duration of saline-sodic water application at the Vitulazio (2 years) site than Torre Lama (5 years). Moreover the difference between Torre Lama and Vitulazio might depend from the difference in the type of clay minerals. In fact at Vitulazio there is an abundance of smectite-type clay in the soil. Despite the difference in total porosity of the two sites the soil water available (AW) calculated in the range of 100 cm and 104 cm pressure head, for a layer of 100 cm depth, show a similar trend at the two sites. At Torre Lama for all the irrigation frequencies and depths considered, the non-saline treatment had lower AW-values than the saline treatments. At Vitulazio, even if the total porosity was in contrast with Torre Lama, the calculated soil water available had the same trend. In fact the I0 treatment at Vitulazio had an AW-value of 128.1 mm against the 178.4 mm of the I1 treatment. The total porosity at Torre Lama changes from about 29% (I0 treatment) to 20% for the I1. Moreover for the Vitulazio site the total porosity changes from a value of 21% for the I0 treatment, to 15% for the I1 treatment. The numerical experiments have shown that the already clear difference in h(q) and K(h) of the I0 and I1 treatments is reflected in significantly higher AW values of I1 against the I0 throughout the year. The persistence of soil water deficit is also lower for the I1 than for the I0 treatment, as shown by the lower number of days with AW < soil water retention capacity.

Gas exchanges of whole canopy can be studied by covering entire plants with a chamber and using portable infrared gas analyzers (IRGAs) to measure CO2 and H2O exchanged with the air blown through the chamber enclosure. The control of temperature rise inside the chamber, which should be kept low, and the accurate measurement of the air flow are two crucial aspects for realistic and precise estimation of photosynthesis and transpiration. An automated open-system plant chamber (clear flexible balloon enclosure) for small plants was developed to ameliorate such a technique. The temperature rise is here predicted by heat balance analysis inside the chamber. The analysis shows that when as much as 500 W m2 of solar radiation is converted to sensible heat, a flow rate of 0.98 mol s(-1) (approximately = 20 L s(-1)) of air blown into a cylinder-shaped enclosure (0.8 m high, 0.5 m wide) is adequate to limit temperature increase to 2 K. An improved calibration for the measurement of the chamber airflow was obtained by combining the use of a Pitot tube anemometer with the classical CO2 injection approach. The concentration increase due to the injection of CO2 at a known rate into the chamber was predicted by the air flow calculated from the "Pitot" air velocity. The turbulent regime of air assured that a single-point Pitot measurement was enough for a good estimation (slope = 0.99; R2 = 0.999) of the actual air flow. The open-system chamber was tested on potted sunflower (Helianthus annuus, L.) and maize (Zea mays, L.) plants under variable solar radiation, temperature, and air humidity during the daytime. As expected, similar rates of maximal leaf-area based photosynthesis (about 40 micromol m(-2) s(-1)) were observed in the two species confirming the reliability of our system. The consistency of data also resulted from the typical relationships observed between photosynthetic rate and light.

Sunflower (Helianthus annuus) was grown in both open-field and outdoor potted conditions in Southern Italy, and irrigated with water having electrical conductivity ranging between 0.9 and 15.6 dS m(-1) obtained by different NaCl concentrations. The aim of the work was to study the leaf area and photosynthetic responses of sunflower to mild salt stress. The response curve (A/c(i)) of assimilation (A) to leaf internal CO(2) concentration (c(i)) was used to determine leaf gas-exchange parameters, in order to evaluate stomatal and non-stomatal limitations to photosynthesis in relation to salt stress. In the field, a reduction of 19% in leaf area expansion occurred, while no correlation was observed between Psi(l) and stomatal conductance to water vapour (g(sw)) ranging between 0.76 and 1.35 mol m(-2) s(-1). This result was also evident at a higher salinity level reached in the pot experiment where leaf osmotic potential (psi(s)) varied from -1.35 to -2.67 MPa as compared with the field experiment, where psi(s) ranged from -1.15 to -1.42 MPa. Considering the two experiments as a unique data set, the assimilation rate, the stomatal conductance to CO(2) (g(sc)) and the sensitivity of A to c(i) variation (g*) were not significantly influenced by salinity in the whole range of psi(s). As a consequence, the stomatal and non-stomatal limitations to photosynthesis were not affected by salt treatment, averaging around 20 and 80%, respectively. The variation in A (from 44 to 29 µmol m(-2) s(-1)) was paralleled by the variation in g(sc) (from 0.47 to 0.84 mol m(-2) s(-1)), with a remarkable constancy of both c(i) (200+/-12.5 µmol mol(-1)) and normalized water-use efficiency (5+/-0.7 µmol mmol(-1) kPa), showing the optimal behaviour of the plant processes. These findings indicate that, under mild salt stress, the same as observed under water deficit, sunflower controls assimilation mainly by modulating leaf area rather than by stomatal closure, and that non-stomatal limitation of photosynthesis was not affected at all by the level of salinity reached in this study.