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Several complex and interconnected megatrends such as climate change, environmental degradation, and stagnating yields threaten crop production and world food security for a growing global population (Maggio et al., 2018). This poses the challenge to develop sustainable and resilient agroecosystems with increased productivity as a key objective for the coming decades. In the past, agriculture has expanded production by breeding as well as by increasing inputs and farming areas. However, the projected scenarios call for considerable reductions in agricultural inputs such as water, fertilizers, and agrochemicals to reduce their environmental burden, whilst also addressing the decreasing land availability in many European countries. Integrated solutions and new technologies to improve plant production, based on knowledge-driven innovations in the farming sector and in agricultural and seed industries, have become the key objectives on the way towards sustainable agriculture (da Silva, 2015; Watt et al., 2020; Morisse et al., 2022).

In the scenario of climate change, the availability of genetic resources for tomato cultivation that combine improved nutritional properties and more tolerance to water deficiency is highly desirable. Within this context, the molecular screenings of the Red Setter cultivar-based TILLING platform led to the isolation of a novel lycopene ε-cyclase gene (SlLCY-E) variant (G/3378/T) that produces modifications in the carotenoid content of tomato leaves and fruits. In leaf tissue, the novel G/3378/T SlLCY-E allele enhances β,β-xanthophyll content at the expense of lutein, which decreases, while in ripe tomato fruit the TILLING mutation induces a significant increase in lycopene and total carotenoid content. Under drought stress conditions, the G/3378/T SlLCY-E plants produce more abscisic acid (ABA) and still conserve their leaf carotenoid profile (reduction of lutein and increase in β,β-xanthophyll content). Furthermore, under said conditions, the mutant plants grow much better and are more tolerant to drought stress, as revealed by digital-based image analysis and in vivo monitoring of the OECT (Organic Electrochemical Transistor) sensor. Altogether, our data indicate that the novel TILLING SlLCY-E allelic variant is a valuable genetic resource that can be used for developing new tomato varieties, improved in drought stress tolerance and enriched in fruit lycopene and carotenoid content.

The scarcity of water due to climate change is endangering worldwide the production, quality, and economic viability of growing wine grapes. One of the main mitigation measures to be adopted in the viticulture sector will be an adequate irrigation strategy. Irrigation involves an increasing demand for water, a natural limited resource with increasing availability problems for the foreseeable future. Therefore, the development of a precision irrigation system, which is able to manage the efficient use of water and to monitor the crop water stress, is an important research topic for viticulture. This paper, through the analysis of a case study, aims to describe the prototype of a software platform that integrates data coming from different innovative remote and proximal sensors to monitor the hydric stress status of the vineyard. In addition, by using a cost analysis of grape cultivation and implementing economic indices, this study examines the conditions by which irrigation strategies may be economically justified, helping the decision-making process. By combining different sensors, the platform makes it possible to assess the spatial and temporal variability of water in vineyards. In addition, the output data of the platforming, matched with the economic indices, support the decision-making process for winemakers to optimize and schedule water use under water-scarce conditions.

International audience; The challenges of securing future food security will require deployment of innovative technologies to accelerate crop production. Plant phenotyping methods have advanced significantly, spanning low-cost hand-held devices to large-scale satellite imaging. Field-based phenotyping aims to capture plant response to the environment, generating data that can be used to inform breeding and selection requirements. This in turn requires access to multiple representative locations and capacities for collecting useful information. In this paper we identify the current challenges in access to field phenotyping in multiple locations in Europe based on stakeholder feedback. We present a map of current infrastructure and propose opportunities for greater integration of existing facilities for meeting different user requirements. We also review the currently available technology and data requirements for effective multi-location field phenotyping and provide recommendations for ensuring future access and coordination. Taken together we provide an overview of the current status of European field phenotyping capabilities and provides a roadmap for their future use to support crop improvement. This provides a wider framework for the analysis and planning of field phenotyping activities for crop improvement worldwide.

This review provides a wide-ranging assessment of approaches to reduce the impact of heat stress on food crops., To ensure the food security of future generations and to address the challenge of the ‘no hunger zone’ proposed by the FAO (Food and Agriculture Organization), crop production must be doubled by 2050, but environmental stresses are counteracting this goal. Heat stress in particular is affecting agricultural crops more frequently and more severely. Since the discovery of the physiological, molecular, and genetic bases of heat stress responses, cultivated plants have become the subject of intense research on how they may avoid or tolerate heat stress by either using natural genetic variation or creating new variation with DNA technologies, mutational breeding, or genome editing. This review reports current understanding of the genetic and molecular bases of heat stress in crops together with recent approaches to creating heat-tolerant varieties. Research is close to a breakthrough of global relevance, breeding plants fitter to face the biggest challenge of our time.

Currently, the transport of ions and nutrients in the plant stem is determined by destructive techniques or by radiolabeled compounds. Here, we have combined materials science and mathematical modelling to develop a sensor device that can monitor in real time and simultaneously the concentration of ions and the saturation in the plant’s xylem. The device, based on the technology of organic electrochemical transistors, is biomimetic, biocompatible, low-cost and minimally invasive. The mathematical model decodes the sensor’s response and decouples the effects of concentration and saturation over time. In the work, we demonstrated the scheme by monitoring the condition of tomato plants subjected to vapor pressure deficit and drought stress for up to 25 days. Results of the work have the potential to impact on the analysis of plant’s physiology, improve water use efficiency in small and large-scale agriculture, and maximize yield with a minimum amount of fertilizer/nutrients.

The production of many food items processed from wheat grain relies on the use of high gluten strength flours. As a result, about 80% of the allelic variability in the genes encoding the glutenin proteins has been lost in the shift from landraces to modern cultivars. Here, the allelic variability in the genes encoding the high molecular weight glutenin subunits (HMW-GSs) has been characterized in 152 durum wheat lines developed from a set of landraces. The allelic composition at the two Glu-1 loci (Glu-A1 and -B1) was obtained at both the protein and the DNA level. The former locus was represented by three alleles, of which the null allele Glu-A1c was the most common. The Glu-B1 locus was more variable, with fifteen alleles represented, of which Glu-B1b (HMW-GSs 7 + 8), -B1d (6 + 8) and -B1e (20 + 20) were the most frequently occurring. The composition of HMW-GSs has been used to make inferences regarding the diffusion and diversification of durum wheat. The relationships of these allelic frequencies with their geographical distribution within the Mediterranean basin is discussed in terms of gene-ecology.

The release of several wheat reference genome sequences lays the basis for accelerating wheat improvement. However, additional effort is require to capture/exploit native variability. Triticum turgidum genetic resources provide a rich diversity reservoir, valuable for both durum and common wheat. We collected iSelect 90K wheat SNP data for 1,856 accessions from 11 tetraploid wheat taxa, including wild and domesticated emmer wheat (WEW and DEW), durum landraces (DWL) and modern durum cultivars (DWC), known as Global Tetraploid wheat Collection (GTC). Infinium raw data were processed under a unique pipeline and over 23,000 SNPs were anchored to Svevo genome. WEW and DEW were highly structured while DWL showed high admixture already at low k values. WEW germplasm was split into North-Eastern and Southern Levant Fertile Crescent populations (WEW-NE and WEW-SL, respectively) and many subpopulations. DEW and DWL showed two similar but independent radial dispersal patterns including six main populations each following North/South and Fertile Crescent to Mediterranean basin and Greece-to-Balkans (Western), Iran-to-Transcaucasia and Oman-to-India, Ethiopia (Eastern) spread. Domestication bottlenecks and haplotype transmission rate were traced for the three main transitions (WEW-to-DEW early domestication, DEW-to-DWL and DWL-to-DWC evolution under domestication). WEW had the highest, evenly distributed diversity, thus providing the reference for assessing diversity reductions. Diversity reduction index (DRI), Fst, haplotype-based XP-EHH, hapFLK and XP-CLR metrics served to produce a selection/demography signal map. In total, 104 pericentromeric (average size of 107.7 Mb) and 350 non-pericentromeric (average size of 11.4 Mb) signal clusters were identified. Numerous strong diversity depletions characterized the WEW-to-DEW transition, for 2Gb in total. These signals progressively consolidated through domestication and breeding and novel signals were found, affecting up to 5Gb in DWC. WEW-to-DEW signals involved extended pericentromeric regions tagged by DRI and Fst while DEW-to-DWL and DWL-to-DWC were mostly associated to numerous XP-EHH and XP-CLR signals. Nevertheless, DEW-to-DWL-specific strong signals were observed in chromosomes 1A, 1B, 2B, 3B, 7A, 7B. Genome-wide haplo-blocks were transmitted from WEW-NE and WEW-SL to DEW with a 0.65/0.35 overall inheritance ratio. Based on haplo-block transmission rate in selected key-regions, durum wheat (DWL) most probably originated from the Southern-levant and SL-to-Europe DEW. Modern durum originated mostly from the North-African and Transcaucasian DWL. Ethiopian germplasm, T.turanicum and T.carthlicum were the most differentiated with minimal contribution to modern durum. Our results show the usefulness of the GTC to elucidate the evolutionary patterns associated to loci, haplotype blocks and causative sequence variants for traits of breeding interest.

Wheat, among all cereal grains, possesses unique characteristics conferred by gluten; in particular, high molecular weight glutenin subunits (HMW-GS) are of considerable interest as they strictly relate to bread-making quality and contribute to strengthening and stabilizing dough. Thus, the identification of allelic composition, in particular at the Glu-B1 locus, is very important to wheat quality improvement. Several PCR-based molecular markers to tag-specific HMW glutenin genes encoding Bx and By subunits have been developed in recent years. This study provides a survey of the molecular markers developed for the HMW-GS at the Glu-B1 locus. In addition, a selection of molecular markers was tested on 31 durum and bread wheat cultivars containing the By8, By16, By9, Bx17, Bx6, Bx14 and Bx17 Glu-B1 alleles, and a new assignation was defined for the ZSBy9_aF1/R3 molecular marker that was specific for the By20 allele. We believe the results constitute a practical guide for results that might be achieved by these molecular markers on populations and cultivars with high variability at the Glu-B1 locus.

The technological quality of wheat flour is defined by a range of dough characteristics relevant to the breadmaking processes and practices of individual countries and for particular products. The influence of storage protein diversity on wheat quality has been widely documented in the last three decades. The present chapter focuses on several aspects of wheat quality that merit more attention. The huge genetic diversity of wheat storage proteins means that all the possible allelic combinations and their interactions are too numerous to be tested in terms of their influence on the major quality parameters. However it is still relevant to describe the variation in rheological and viscoelastic properties of gluten in relation to its component proteins, glutenin and gliadin. Although gluten plays a major role in determining the properties of dough, the abundance of the two major storage protein fractions does not solely explain the observed variation in those properties. We therefore examine the influence of some genetic factors, including those affecting the protein composition, on the variation in the glutenin polymer sizes. Some examples will be given to illustrate how end-use quality can be improved by taking advantage of the available genetic resources in parallel with molecular genome analyses with the dual aim of widening the scope of characteristics that can be harnessed in breeding and ensuring consistent wheat quality in changing agro-climatic situations. The known alleles of the major genes are highlighted in the context of the challenges that the research community is facing regarding wheat allele nomenclature, exchange of gene bank material and the numerous quality attributes of interest. Finally, important research objectives are proposed for breeding future wheats with grain protein quality and technological properties tailored for different food products.

The assembled Svevo durum wheat genome and the iSelect wheat 90K SNP array were used as a base to characterize a world-wide tetraploid wheat collection. We report on the diversity pattern of 1,854 non-redundant accessions from all known Triticum turgidum subspecies. The genetic diversity survey relied on a common genotype-calling pipeline from AgriBio supported by 17 tetraploid linkage maps. The pipeline yielded 17,416 informative single-locus SNPs anchored to the Svevo genome. Among the wild emmer (WEW), domesticated emmer (DEW), durum wheat landraces (DWL) and durum wheat cultivars (DWC), WEW showed the highest and uniform diversity across the whole genome, providing a reference for cross-comparison with DEW, DWL and DWC. Extended diversity depletions associated to domestication were found particularly in pericentromeric regions. Some 38.2% of DW genome was affected by strong genetic bottleneck/selection events leading to diversity depletions. Six extended regions showed increased genetic diversity associated to DEW-DWL and DWL-DWC transitions. Population structure revealed multiple subsequent events of population differentiation associated to human-driven dispersal routes. This analysis provides the basis for a more informative re-sequencing towards a tetraploid pan-genome. Sub-panels have already been used for GWAS analysis, allowing us to identify GWAS-QTL that can be readily used in breeding. GWAS-QTLs for grain yield components (grain size and grain number per spike) and resistance to diseases have been identified using a subpanel of Mediterranean DW landraces. These resources allowed us to map QTLs at an improved resolution (1 cM confidence interval) and readily scan the genome for underlying candidate genes.

Organic electrochemical transistors (OECTs) are transducing devices that, placed in contact with an electrolyte solution, detect the ionic composition of that solution by measuring the channel current $I$ . OECTs enable the streaming of continuously updated zero-to-low latency information and show, therefore, promise for being used as highly efficient biosensors. Nevertheless, apart from simple geometries, decoding such an information may be infeasible. Here, we show how $I$ can be processed to derive a reduced set of two variables that account for most of the information of a system: 1) the modulation $m$ is the current gained by the system compared to its initial value; and 2) the effective time $t_{e}$ is the time over which the response of the system stays above the 65% of its final value. $m$ and $t_{e}$ can be reported in a diagram that is akin to the state space diagrams used in thermodynamics: points in the diagram describe the state of a system at a specific time; trajectories in the diagram describe the time evolution of that system. We show that the total electric charge $Q$ exchanged by the system between two states A and B is independent on the path taken between them. This, in turn, implies that $m$ and $t_{e}$ are state variables of the system. In experiments with Solanum lycopersicum tomato plants, we show how this concept can be used to extract relevant information about a biophysical system without direct knowledge of its internal workings.

A large wealth of genetic diversity is present in the diversity centers of durum wheat. However, modern breeding selection methods are mostly based on improvement of élite lines which have a narrow genetic base; this limits a lot the genetic pool which breeders can exploit for the production of new varieties ready to face the predicted climate changes or adaptation to new cultivation areas. The oncoming changing climatic conditions claim for the need of finding new adaptation traits to both abiotic and biotic stresses to be introduced in modern élite varieties. These traits are often found in landraces stored in germplasm collections. The Eurisco database reports a total of over 17,000 durum accessions, some 6,800 of which are traditional varieties and/or landraces: Besides their incontestable usefulness, their great number hampers the possibility to explore their genepool. A different approach to reduce the number of genotypes to screen for new useful traits to use in breeding programs while maintaining a good representation of the genetic background, is the constitution of a working durum wheat collection selected by mean of a single seed descent (SSD) approach so far called SSD genotypes. The working collection, accounts for over approximately 450 genotypes representative of 40 countries mainly concentrated in the Mediterranean area and Horn of Africa. The SSD genotypes were subjected to large scale SNP screening by ILLUMINA Infinium iSelect 90k wheat chip and the data were analysed to assess the heterozygosity and the genetic diversity present in the SSD population. Moreover the population was preliminary phenotyped following field growth. Both analyses give the picture of a good level of genetic variability represented in the SSD genotypes. This makes this collection a good candidate for a new "genetool" for durum wheat breeding and research.

Several approaches are available to achieve multi-transgene-stacking in plants for the introduction of complex or multiple traits. We used co-transformation with multiple plasmids using particle bombardment and hybridization of plants carrying separate transgenes in wheat. In the co-transformation approach, four constructs containing the defence genes Pvpgip2, Acpmei, Taxi-III or Xip-III and the bar gene were co-bombarded into immature embryos of durum or common wheat. The four transgenes integrated into the wheat genome at co-transformation frequencies of 58 and 27 % in durum and common wheat, respectively. Segregation analysis of the T1 and T2 generations showed that 45–90 % of the progeny inherited all four transgenes together in both durum and common wheat. In the hybridization approach, pyramiding of Pvpgip2, Acpmei and Taxi-III was achieved by crossing durum wheat plants containing the Pvpgip2 and Acpmei transgenes with transgenic plants carrying Taxi-III. Segregation analysis showed that only 4.5 % of the progeny inherited all four transgenes together, including the bar gene. Co-expression analyses of Pvpgip2, Acpmei and Taxi-III or Xip-III showed loss of mRNA or protein activity in the progenies of both transgenic and hybrid wheat lines. Particle bombardment yielded progenies with either tightly linked transgenes or with different transgene combinations that could be useful in research applications. However, its efficiency was constrained by the occurrence of transgene silencing.

Polygalacturonase-inhibiting proteins (PGIPs) are cell wall leucine-rich repeat (LRR) proteins involved in plant defence. The hexaploid wheat (Triticum aestivum, genome AABBDD) genome contains one Pgip gene per genome. Tapgip1 (B genome) and Tapgip2 (D genome) are expressed in all tissues, whereas Tapgip3 (A genome) is inactive because of a long terminal repeat, Copia retrotransposon insertion within the coding region. To verify whether Tapgip1 and Tapgip2 encode active PGIPs and are involved in the wheat defence response, we expressed them transiently and analysed their expression under stress conditions. Neither TaPGIP1 nor TaPGIP2 showed inhibition activity in vitro against fungal polygalacturonases. Moreover, a wheat genotype (T. turgidum ssp. dicoccoides) lacking active homologues of Tapgip1 or Tapgip2 possesses PGIP activity. At transcript level, Tapgip1 and Tapgip2 were both up-regulated after fungal infection and strongly induced following wounding. This latter result has been confirmed in transgenic wheat plants expressing the ?-glucuronidase (GUS) gene under control of the 5?-flanking region of Tdpgip1, a homologue of Tapgip1 with an identical sequence. Strong and transient GUS staining was mainly restricted to the damaged tissues and was not observed in adjacent tissues. Taken together, these results suggest that Tapgips and their homologues are involved in the wheat defence response by acting at the site of the lesion caused by pathogen infection.

The in vivo monitoring of key plant physiology parameters will be a key enabler of precision farming. Here, a biomimetic textile-based biosensor, which can be inserted directly into plant tissue is presented: the device is able to monitor, in vivo and in real time, variations in the solute content of the plant sap. The biosensor has no detectable effect on the plant’s morphology even after six weeks of continuous operation. The continuous monitoring of the sap electrolyte concentration in a growing tomato plant revealed a circadian pattern of variation. The biosensor has the potential to detect the signs of abiotic stress, and therefore might be exploited as a powerful tool to study plant physiology and to increase tomato growth sustainability. Also, it can continuously communicate the plant health status, thus potentially driving the whole farm management in the frame of smart agriculture.

In vivo integrated plant monitoring by biocompatible devices represents a key point for precision farming. Increasing effortsin research development have been done to preserve natural environment and increase crop yield, developing newmethodologies that allow the application of the "right treatment in the right place at the right time". Here a biomimetic textilebiosensor has been implemented in tomato plants, to monitor their ionic activity, during growth and development, directlyintegrated in plant tissues. The active channel of the biosensor is prepared using a textile fiber, directly incorporated in theplant stem and the device presents a textile Organic Electro Chemical Transistor architecture. The response of the sensors,calculated as modulation of channel current, together with the kinetic characteristic of the signal, have been monitored inseveral tomato plants for six weeks. Thus, the biological activity of several tomato plants has been constantly monitored, bymeasuring the concentrations of electrolytes in the plant lymph at different gate voltages. The devices detected cyclicalmodifications which match with the typical night/day alternation. An innovative data analysis system, that combines thequantitative response with kinetic characteristics of the signal, was introduced to improve sensitivity and increase thesignificance of the collected information. The data confirm the ability of the biosensor to monitor cyclic behavior ofbiochemical characteristics of tomato sap, controlling their fine modifications. The proposed biosensors did not alter theplant morphology even after six weeks of operations and thus resulted perfectly integrated within the plant tissues, thanksto the biomimetic structure of the natural textile fibers. The information on biochemistry of the plant sap can give an insightview on the plant conditions, and allow the optimization of their irrigation and nutrition. The combination of this novelbiological dependent transistor, which we call "bioristor", together with biochemical and statistical analysis represent an earlydetection of the plant physiological conditions that allow to optimize growth conditions and rapidly act for plant recovery incase of stress.G. Tarabella, et Al. J. of Mat. Chem. 22 (2012) 23830-23834.N. Coppedè, et Al. J. of Mat. Chem. B, 2 (2014) 5620-5626.E. Battista, et Al. Organic Electronics, 40 (2017) 51-57

With 6 figures and 1 table Abstract The granule-bound starch synthase (GBSS), known as waxy protein, is the sole enzyme responsible for amylose synthesis, whereas amylopectin is produced by concerted action of several isoforms, including starch synthases, branching and debranching enzymes. Durum wheat contains two waxy genes, which encode the Wx-A1 and Wx-B1 proteins, respectively. In order to investigate the effect of the overexpression of the waxy genes on amylose content and starch properties, durum wheat transgenic lines overexpressing the Wx-B1 gene were produced. Amylose content of the transgenic lines did not show any increase compared to the untransformed cultivar. One of the transgenic lines was crossed with a mutant waxy genotype of durum wheat lacking all the waxy protein isoforms. The screening of F2 segregant plants permitted the identification of lines possessing various combinations of waxy genes, including the line containing only the construct used in the transformation. In this line, the normal vitreous seed phenotype, because of the presence of amylose, was restored confirming a correct functioning of the transgene.

Fusarium head blight (FHB), caused by Fusarium graminearum, is one of the most important diseases of wheat worldwide, resulting in yield losses and mycotoxin contamination. The molecular mechanisms regulating Fusarium penetration and infection are poorly understood. Beside mycotoxin production, cell wall degradation may play a role in the development of FHB. Many fungal pathogens secrete polygalacturonases (PGs) during the early stages of infection, and plants have evolved polygalacturonase-inhibiting proteins (PGIPs) to restrict pectin degradation during fungal infection. To investigate the role of plant PGIPs in restricting the development of FHB symptoms, we first used Arabidopsis thaliana, whose genome encodes two PGIPs (AtPGIP1 and AtPGIP2). Arabidopsis transgenic plants expressing either of these PGIPs under control of the CaMV 35S promoter accumulate inhibitory activity against F. graminearum PG in their inflorescences, and show increased resistance to FHB. Second, transgenic wheat plants expressing the bean PvPGIP2 in their flowers also had a significant reduction of symptoms when infected with F. graminearum. Our data suggest that PGs likely play a role in F. graminearum infection of floral tissues, and that PGIPs incorporated into wheat may be important for increased resistance to FHB.

Manipulation of starch composition in cereals and particularly in wheat is receiving increasing attention due to recognition of its important role in food and nonfood applications. The amylose/ amylopectin ratio influences the physicochemical properties of starches and nutritional value of derived end products. Identification of the key enzymes involved in the starch biosynthetic pathway has opened new avenues for altering the amylose and amylopectin content in durum and bread wheat. The granule bound starch synthases (GBSSI), or waxy proteins, are the enzymes responsible for amylose synthesis in storage tissues; amylopectin is produced by the concerted action of different enzymes, including starch synthases (SS), branching (SBE), and debranching enzymes (DBE). By altering the level of key enzymes involved in the regulation of starch synthesis, it is possible to generate novel starches with unique functional properties. In this respect, both low and high amylose starches are particularly interesting because they are associated with industrial and processing properties as well as with human health and nutrition. So far, major attention has addressed the manipulation of starch composition in bread wheat,whereas durum wheat has been investigated to a much lesser extent. Approaches currently available to alter amylose/amylopectin ratio and tailor starch composition in durum wheat are presented.

Correspondance: dovidio@unitus.it; International audience; Polygalacturonase-inhibiting proteins (PGIPs) are leucine-rich repeat (LRR) proteins involved in plant defence. Wheat pgip genes have been isolated from the B (Tapgip1) and D (Tapgip2) genomes, and now we report the identification of pgip genes from the A genomes of wild and cultivated wheats. By Southern blots and sequence analysis of BAC clones we demonstrated that wheat contains a single copy pgip gene per genome and the one from the A genome, pgip3, is inactivated by the insertion of a long terminal repeat copia retrotranspon within the fourth LRR. We demonstrated also that this retrotransposon insertion is present in Triticum urartu and all the polyploidy wheats assayed, but is absent in T. monococcum (Tmpgip3), suggesting that this insertion took place after the divergence between T. monococcum and T. urartu, but before the formation of the polyploid wheats. We identified also two independent insertion events of new Class II transposable elements, Vacuna, belonging to the Mutator superfamily, that interrupted the Tdipgip1 gene of T. turgidum ssp. dicoccoides. The occurrence of these transposons within the coding region of Tdipgip1 facilitated the mapping of the Pgip locus in the pericentric region of the short arm of chromosome group 7. We speculate that the inactivation of pgip genes are tolerated because of redundancy of PGIP activities in the wheat genome