Claudio Lovisolo

University of Turin | UNITO · Department of Agricultural, Forest and Food Sciences

A major issue in several farming areas of the Mediterranean basin consists of drought and salinity stress. This stress is mainly due to a steady exposition of warm daily temperature and heatwaves, moreover with inevitable irrigation with saline water. Therefore, detecting the stress is essential to minimise significant yield loss and preserve agric...

Flavescence dorée (FD) is a phytoplasma disease transmitted by insects, causing severe damage to vineyards across Europe. Infected plants cannot be cured and must be removed to prevent further spread. Different grapevine cultivars show varying susceptibility to FD, and some exhibit symptom remission, known as recovery, although the mechanisms behin...

The DOWNY MILDEW RESISTANCE 6 (DMR6) protein is a 2-oxoglutarate (2OG) and Fe(II)-dependent oxygenase, involved in salicylic acid (SA) metabolism, and its inactivation in tomato was found to increase SA levels and to confer disease-resistance against several pathogens. SA is also recognized as an abiotic stress-tolerance enhancer, and we tested the...

Coffee is one of the most traded commodities world‐wide. As with 70% of land plants, coffee is associated with arbuscular mycorrhizal (AM) fungi, but the molecular bases of this interaction are unknown. We studied the mycorrhizal phenotype of two commercially important Coffea arabica cultivars (‘Typica National’ and ‘Catimor Amarillo’), upon Funnel...

To understand how grapevine sinks compete with each other during water stress and subsequent rehydration, carbon (C) allocation patterns in drought‐rehydrated vines (REC) at the beginning of fruit ripening were compared with control vines maintained under drought (WS) or fully irrigated (WW). In the 30 days following rehydration, the quantity and d...

To measure gas exchange at the whole plant (WP) level, design solutions were provided and prototypes of gas-exchange systems (GESs) were tested to carry out shoot and rootzone analyses in plants of different sizes. A WP-GES for small herbaceous plants was tested on the ability to maximize the net assimilation rate of CO2 in lettuce plants grown eit...

La micro tomografia computerizzata a raggi X (Micro Computed X-Ray Tomography) è una tecnica di visualizzazione digitale tridimensionale non distruttiva di oggetti solidi. In un tempo relativamente breve e senza alcuna forma di contatto, con la scansione tomografica è possibile ottenere il modello volumetrico che descrive le geometrie interne ed es...

Along with the ongoing climate change, drought events are predicted to become more severe. In this context, the Spray Induced Gene Silencing (SIGS) technique could represent a useful strategy to improve crop stress resilience. A previous study demonstrated that the Arabidopsis mutants for a glutathione S-transferase (GST) gene had increased abscisi...

Abstract: Strigolactones (SLs) have been implicated in many plant biological and physiological processes, including the responses to abiotic stresses such as drought, in concert with other phytohor-mones. While it is now clear that exogenous SLs may help plants to survive in harsh environmental condition, the best, most effective protocols for trea...

In drought‐stressed plants a coordinated cascade of chemical and transcriptional adjustments occurs at the same time as embolism formation. While these processes do not affect embolism formation during stress, they may prime stems for recovery during rehydration by modifying apoplast pH and increasing sugar concentration in the xylem sap. Here we s...

miR156 is a conserved microRNA whose role and induction mechanisms under stress are poorly known. Strigolactones are phytohormones needed in shoots for drought acclimation. They promote stomatal closure ABA‐dependently and independently; however, downstream effectors for the former have not been identified. Linkage between miR156 and strigolactones...

The first serious outbreak of Flavescence dorée (FD) in Piedmont (North-West Italy) dates back to 1998 in the Tortona area (Alessandria province). FD is a serious quarantine-worthy disease transmitted by the leafhopper Scaphoideus titanus Ball. Different Vitis vinifera L. biotypes react differently to the phytoplasma, in particular as to the accumu...

Sage is an important medicinal and aromatic plant. While Salvia officinalis and S. miltiorrhiza have been widely studied, little information regarding S. dolomitica exists, although it has recently attracted attention due to its anti-plasmodial and anti-inflammatory properties. This study investigated the performance and metabolic profile of this s...

Dehydration/shrinking of grape berries during late ripening is a common disorder of grapevine cultivars and has deleterious implications for yields and grape quality.

Salvia sinaloensis Fern. (sage) is a medicinal plant containing plant secondary metabolites (PSMs) with antioxidant properties. The current study investigated the effects of drought stress on S. sinaloensis morphological and ecophysiological traits, and active constituent production. Sage plants were cultivated in controlled conditions for 34 days...

The berry shrinking phenomenon in cv Shiraz (Vitis vinifera L.) is to date much debated. Currently, the critical points in Shiraz pre-harvest shrinkage are: a) the role of the xylem during post-véraison; b) the existence and timing of xylematic back flow and c) the functionality of the phloem. In order to try to resolve these issues, we traced the...

Efficient irrigation practices are required to reduce the amount of water used. In this study, the effects of different irrigation regimes on changes in growth, ecophysiology and ornamental traits of potted Primula vulgaris ‘Heidy’ plants were investigated. Three experiments were carried out. In the first, the plants were either fully irrigated (10...

Grapevine (Vitis vinifera L.) is routinely grafted and rootstocks inducing drought tolerance represent a source for adapting vineyards to climate change in temperate areas. Our goal was to investigate drought stress effects on miRNA abundance in a drought-resistant grapevine rootstock, M4 (Vitis vinifera X Vitis berlandieri), compared with a commer...

The main factors regulating grapevine response to decreasing water availability were assessed under statistical support using published data related to leaf water relations in an extensive range of scion and rootstock genotypes. Matching Ψleaf and gs data were collected from peer-reviewed literature with associated information. The resulting databa...

• Strigolactones (SL) contribute to drought acclimatization in shoots, since SL-depleted plants are hypersensitive to drought due to stomatal hyposensitivity to abscisic acid (ABA). However, under drought, SL biosynthesis is repressed in roots, suggesting organ specificity in their metabolism and role. Since SL can be transported acropetally, such...

Abstract: The aquaporin specific control on water versus carbon pathways in leaves is pivotal in controlling gas exchange and leaf hydraulics. We investigated whether NtAQP1 and NtPIP2;1 gene expression varies in tobacco leaves subjected to treatments with different CO2 concentrations (ranging from 0 to 800 ppm), inducing changes in photosynthesis,...

Hydraulic capacitance in a plant tissue (C) buffers the xylem tension, storing and releasing water and has been highlighted in recent years as an important factor that affects water relations such as drought tolerance and embolism formation. Aquaporins are well known to control leaf hydraulic resistance (Rh) but their role in the control of C is un...

Drought signalling among grapevine organs has a dual component: a hydraulic signal controlled by xylem physiology coexists with chemical signals (involving hormones, especially abscisic acid, ABA), transported via xylem, phloem and parenchyma pathways. Under water deficits, with high levels of tension developing, gas-filled xylem vessels may become...

Grapevine adaptations to water-stress are described, by focusing on soil/root interactions and root-to-shoot signaling to control both plant water relations and fruit ripening process. Root response to drought, tolerance of available rootstock germoplasm, mechanisms of embolism formation and repair in root, aquaporin control of plant water relation...

MicroRNAs (miRNAs) are small non-coding RNAs that regulate the post-transcriptional control of several pathway intermediates, thus playing pivotal roles in plant growth, development and response to biotic and abiotic stresses. In recent years, the grapevine genome release, small(s)-RNAseq and degradome-RNAseq together has allowed the discovery and...

The genus Helichrysum Miller is a source of many bioactive metabolites commonly used in traditional medicine. In particular, Helichrysum petiolare Hilliard & B.L. Burtt shows activities as antiseptic, anti-inflammatory and in the control of anxiety disorder. Biosynthesis and accumulation of secondary metabolites is a defense mechanism of plants and...

Main conclusion: Strigolactone changes and cross talk with ABA unveil a picture of root-specific hormonal dynamics under stress. Strigolactones (SLs) are carotenoid-derived hormones influencing diverse aspects of development and communication with (micro)organisms, and proposed as mediators of environmental stimuli in resource allocation processes...

For sustainable agriculture productivity and environmental quality, composts are considered as substitutes of chemical fertilizers. They are applied to soil at tens-hundreds dry matter ton ha-1 yearly dose to contribute organic C and N and minerals. Hereinafter, municipal biowaste compost and its hydrolysate products are reported to enhance maize p...

Drought signalling among grapevine organs has a dual component: a hydraulic signal controlled by xylem physiology coexists with chemical signals (involving hormones, especially abscisic acid, ABA), transported via xylem, phloem and parenchyma pathways. Under water deficits, with high levels of tension developing, gas-filled xylem vessels may become...

This review deals with grapevine abscisic-acid (ABA) mediated responses to abiotic stress by addressing stress consequences mainly on berry quality. Accumulation of secondary metabolites as a plant defense strategy to abiotic stress is reviewed, together with perturbations of metabolite molecular pathways. The role of ABA is highlighted as a link b...

Several beneficial rhizospheric microorganisms, such as arbuscular mycorrhizal fungi (AMF) and Plant Growth Promoting Rhizobacteria (PGPR), can improve the tolerance of plants to water deficiency and other environmental stresses. In this work the addition to soil of selected rhizospheric microbial consortia was tested in order to increase tolerance...

Grapevine (Vitis vinifera L.) expresses different responses to water stress, depending not only on genotype, but also on the influence of vineyard growing conditions or seasonality. Our aim was to analyse the effects on drought response of two grapevine cultivars growing on two soils, one water draining (WD) containing sand 80% volume and the other...

In this work, the involvement of vessel-associated cells in embolism recovery was investigated by studying leaf petiole hydraulics and expression profiles of aquaporins and genes related to sugar metabolism. Two different stress treatments were imposed onto grapevines to induce xylem embolism: one involved a pressure collar applied to the stems, wh...

p style="text-align: justify;"> Aim : Measurement of leaf area in grapevine has always been a critical point in researches focused on irrigation management, training systems, source-sink interrelationships and efficiency of spray application to canopies. In this work, we propose the use of ultrasonic sensors as a fast and accurate tool for the esti...

Aims: All components of the soil-plant-atmosphere (s-p-a) continuum are known to control berry quality in grapevine (Vitis vinifera L.) via ecophysiological interactions between water uptake by roots and water loss by leaves. The scope of the present work was to explore how the main hydraulic components of grapevine influence fruit quality through...

Flavescence dorée (FD) is among the major grapevine diseases causing high management costs; curative methods against FD are unavailable. In FD‐infected plants, decrease in photosynthesis is usually recorded, but deregulation in stomatal control of leaf gas exchange during FD infection and recovery is unknown. We measured the seasonal time course of...

Strigolactones (SLs) are newly identified hormones that regulate multiple aspects of plant development, infection by parasitic weeds, and mutualistic symbiosis in the roots. In this study, the role of SLs was studied for the first time in the model plant Lotus japonicus using transgenic lines silenced for CAROTENOID CLEAVAGE DIOXYGENASE 7 (LjCCD7),...

Quantification of leaf area in grapevine has always been a critical point in researches focused on irrigation management, source-sink interrelationships and efficiency of spray application to canopies. In this work we propose the use of ultrasonic sensors as a fast and accurate tool for the estimation of large portions of leaf canopy area. One ultr...

Plants are in danger of embolism formation in xylem vessels when the balance between water transport capacity and transpirational demand is compromised. To maintain this delicate balance, plants must regulate the rate of transpiration and, if necessary, restore water transport in embolized vessels. Abscisic acid (ABA) is the dominant long-distance...

Strigolactones (SLs) are a group of plant-exuded terpenoid lactones, initially known as the triggering signals for seed germination of parasitic weeds, and more recently for hyphal branching of arbuscular mycorrhizal fungi. In 2008 they were defined as a new class of plant hormones controlling plant architecture. Since then, great advances have bee...

We functionally characterized the grape (Vitis vinifera) VvPIP2;4N (for Plasma membrane Intrinsic Protein) aquaporin gene. Expression of VvPIP2;4N in Xenopus laevis oocytes increased their swelling rate 54-fold. Northern blot and quantitative reverse transcription-polymerase chain reaction analyses showed that VvPIP2;4N is the most expressed PIP2 g...

In this work we compared for two years (2010 and 2011) the anthocyanin content of Nebbiolo berries harvested in three vineyards (Alba, Serralunga and Novello, Cuneo Province, Italy) characterized by different rootstock, soil and climate conditions. A meteorological station was located in each vineyard. In the Serralunga vineyard, wireless micro-sen...

Fast and efficient recovery from water stress is a key determinant of plant adaptation to changing meteorological conditions modulating transpiration, i.e. air temperature and humidity. We analysed transcriptomic responses during rehydration after water stress in grapevine leaf petioles, where embolism formation and repair commonly take place, and...

The aim of this chapter is to assess the interplay of hydraulic conductance and xylem embolism (cavitation) in root, in shoot, in leaf and in the whole grapevine. To measure hydraulic conductance, three main methods are available, which are based on evaporating (EFM), pulling (VPM) or pushing (HPM) water out of the plant organ. The three methods ar...

This review deals with grapevine responses to water stress by examining perturbations to physiological and molecular processes at the root, shoot, leaf and berry levels. Long-distance signalling among organs is also considered. Isohydric or anisohydric Vitis genotypes are described in relation to their response to drought, which is linked to stomat...

A three-year (2004-2006) study to evaluate some physiological aspects of hazelnut trees grown in different training systems was performed in two orchards of 'Tonda Gentile delle Langhe' cultivar located in a hilly area of the Piedmont region (North-Western Italy). In the first orchard two training systems, free vase (monotrunk form) and bush with t...

In this review, we address the main aspects of grapevine (Vitis vinifera L.) resistance to water stress. We point to examine physiological and molecular answers, involving both primary and secondary metabolisms. The grapevine has been generally classified as drought-avoiding or as “pessimistic” following the ecological classification of plants into...

In this review, we address the main aspects of grapevine (Vitis vinifera L) resistance to water stress. We point to examine physiological and molecular answers, involving both primary and secondary metabolisms. The grapevine has been generally classified as drought-avoiding or as "pessimistic" following the ecological classification of plants into...

* Proposed mechanisms of embolism recovery are controversial for plants that are transpiring while undergoing cycles of dehydration and rehydration. * Here, water stress was imposed on grapevines (Vitis vinifera), and the course of embolism recovery, leaf water potential (Psi(leaf)), transpiration (E) and abscisic acid (ABA) concentration followed...

The hybrid Richter-110 (Vitis berlandieri x Vitis rupestris) (R-110) has the reputation of being a genotype strongly adapted to drought. A study was performed with plants of R-110 subjected to water withholding followed by re-watering. The goal was to analyze how stomatal conductance (g(s)) is regulated with respect to different physiological varia...

The impact of aquaporin function on plant water balance is discussed. The significance of these proteins for root water uptake, water conductance in the xylem, including embolism refilling and the role of plant aquaporins in leaf physiology, is described. Emphasis is placed on certain aspects of water stress reactions and the correlation of aquapor...

The expression of OePIP1.1 and OePIP2.1 aquaporins in root, stem and leaf was higher in Olea europaea L. (olive) plants carrying a dwarfing (D) clone as rootstock, than in plants carrying a vigorous (M) clone as rootstock. The highest difference of expression between plants with D and M rootstocks was detected in the root and for the PIP2 gene, the...

To investigate the effects of drought and recovery on the transcript level of OePIP2.1 (a PIP2 aquaporin gene) in twigs, 2-year-old olive trees were subjected to a drought/rewatering treatment (the irrigation was suspended for a period of 4 weeks and restored for the following 4 weeks). Twig water potential, twig hydraulic resistance and incidence...

To study the molecular bases of water transport in olive we characterized cDNAs from Olea europaea cv "Leccino" related to the aquaporin (AQP) gene family. A phylogenetic analysis of the corresponding polypeptides confirmed that they were part of water channel proteins localized in the plasma membrane and in the tonoplast. The full-length sequences...