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A. Zhou-Tsang, Y. Wu, S.W. Henderson, A.R. Walker, A.R. Borneman, R.R. Walker and M. Gilliham

Salinization of soil with sodium chloride ions inhibits plant functions, causing reduction of yield of crops. Salt tolerant microorganisms have been studied to enhance crop growth under salinity. This review describes the performance of endophytic fungi applied to crops as a supplement to plant genetics or soil management to alleviate salt stress in crops. This is achieved via inducing systemic resistance, increasing the levels of beneficial metabolites, activating antioxidant systems to scavenge ROS, and modulating plant growth phytohormones. Colonization by endophytic fungi improves nutrient uptake and maintains ionic homeostasis by modulating ion accumulation, thereby restricting the transport of Na+ to leaves and ensuring a low cytosolic Na+:K+ ratio in plants. Participating endophytic fungi enhance transcripts of genes encoding the high Affinity Potassium Transporter 1 (HKT1) and the inward-rectifying K+ channels KAT1 and KAT2, which play key roles in regulating Na+ and K+ homeostasis. Endophytic-induced interplay of strigolactones play regulatory roles in salt tolerance by interacting with phytohormones. Future research requires further attention on the biochemical, molecular and genetic mechanisms crucial for salt stress resistance requires further attention for future research. Furthermore, to design strategies for sustained plant health with endophytic fungi, a new wave of exploration of plant-endophyte responses to combinations of stresses is mandatory.

Aims Predicting drought consequences on forests and fruit crop plantings requires improved understanding of drought responses of both leaf and fine-root resource acquisitive traits (specific leaf area—SLA, specific root surface area—SRA and specific root length—SRL). We hypothesize their responses are coordinated towards integrated plant resource conservation under severe drought. Methods We tested the hypothesis with a greenhouse-based drought experiment on saplings of six Prunus hybrids with a priori known contrasting drought sensitivity. Saplings were subjected to either control (100% field capacity) or severe drought stress treatment (33% evapotranspiration of hybrid-specific control plants). Sample collections were carried out at 30 and at 60 days after the start of treatments, for both control and stressed saplings. Important Findings No hybrid showed concurrent significant decrease of SLA and SRA (or SRL) under severe drought. The fine-root traits of the six hybrids showed two major drought-response scenarios, in particular: (i) increased root tissue density (RTD) and decreased average root diameter without significant change of SRL and (ii) increased RTD and decreased SRL without significant change of average root diameter. Drought responses of leaf gas exchange, SRA, SRL and RTD were closely correlated along a gradient towards resource conservation from control to drought-stressed plants in all hybrids, which was orthogonal to another gradient characterized by a hybrid-dependent decrease of SLA. These findings highlight (i) the multi-dimensionality of root-trait drought responses, (ii) the decoupling between leaf economics and leaf hydraulics and (iii) the covariation of leaf and root hydraulics in terms of trait drought responses. The study contributes to identifying the origin of the multi-dimensionality of root-trait drought response at intraspecific scale, and highlights differential drought–response combinations of leaf and fine-root traits among hybrids to survive under severe soil drought stress.

Lipids have diverse functions in regulating the plasma membrane's cellular processes and signaling mediation. Plasma membrane lipids are also involved in the plant's complex interactions with the surrounding microorganisms, with which plants are in various forms of symbiosis. The roles of lipids influence the whole microbial colonization process, thus shaping the rhizomicrobiome. As chemical signals, lipids facilitate the stages of rhizospheric interactions - from plant root to microbe, microbe to microbe, and microbe to plant root - and modulate the plant's defense responses upon perception or contact with either beneficial or phytopathogenic microorganisms. Although studies have come a long way, further investigation is needed to discover more lipid species and elucidate novel lipid functions and profiles under various stages of plant root-microbe interactions.

Endophytic nitrogen-fixing (diazotrophic) bacteria are essential members of the microbiome of switchgrass (Panicum virgatum), considered to be an important commodity crop in bioenergy production. While endophytic diazotrophs are known to provide fixed atmospheric nitrogen to their host plant, there are many other plant growth-promoting (PGP) capabilities of these organisms to be demonstrated. The diversity of PGP traits across different taxa of switchgrass-colonizing endophytes is understudied, yet critical for understanding endophytic function and improving cultivation methods of important commodity crops. Here, we present the isolation and characterization of three diazotrophic endophytes: Azospirillum agricola R1C, Klebsiella variicola F10Cl, and Raoultella terrigena R1Gly. Strains R1C and F10Cl were isolated from switchgrass and strain R1Gly, while isolated from tobacco, is demonstrated herein to colonize switchgrass. Each strain exhibited highly diverse genomic and phenotypic PGP capabilities. Strain F10Cl and R1Gly demonstrated the highest functional similarity, suggesting that, while endophyte community structure may vary widely based on host species, differences in functional diversity are not a clearly delineated. The results of this study advance our understanding of diazotrophic endophyte diversity, which will allow us to design robust strategies to improve cultivation methods of many economically important commodity crops.

Background and Aims The study compared the viticultural performance and wine sensory attributes of Shiraz grafted on eight rootstocks with a range in vine vigour and grown under drip‐irrigation with moderately saline water. Methods and Results The rootstocks were 140 Ruggeri, 1103 Paulsen, 110 Richter, Ramsey, 101‐14, M5489, M5512 and M6262. Ramsey and 140 Ruggeri had the highest leaf area index and M6262 the lowest. Ramsey had highest yield, followed by 140 Ruggeri > M5489 = 110 Richter > M5512 > 1103 Paulsen = 101‐14 > M6262. Rootstock M6262 had highest wine chloride concentration of 482 and 384 mg/L in 2012 and 2013, respectively, but salty taste and a thickness mouthfeel (viscosity) were significant only in 2012. Wines from the other seven rootstocks had a chloride and sodium concentration under 175 and 40 mg/L, respectively. Colour density was highest in wine from 101‐14 in 2012 and from 101‐14, 1103 Paulsen and M5489 in 2013. A salt tolerance index (STI) for the eight rootstocks was calculated based on yield, leaf area index, grape juice chloride and sodium concentration and wine colour density. Conclusions Rootstock M6262 had lowest STI in both years. M5489 had highest STI in 2013 followed by 110 Richter = M5512 = 101‐14 = 140 Ruggeri. The recognition threshold for salty taste may lie between a chloride concentration in wine of between 384 and 482 mg/L. Significance of the Study The STI, based on five wine grape performance parameters, provides a promising measure of rootstock salt tolerance compared with the traditional parameters of yield and/or capacity for salt exclusion.

Sodium (Na+) exclusion is an important rootstock trait, which contributes to the overall salt tolerance of a grafted vine by limiting Na+ accumulation in both leaves and berries. A population of 68 hybrid Vitis genotypes, presumed to be from a cross between the rootstocks ‘K51-40’ and ‘140 Ruggeri’, have previously been investigated for their ability to exclude Na+. Here we report that the genotyping of this population with eight short sequence repeat (SSR) markers showed that ‘140 Ruggeri’ is the male parent of only 40 individuals. The rootstock ‘Schwarzmann’ is the male parent of 18 genotypes, with the remaining 10 genotypes being derived from unknown pollen sources. The role of HKT1;1 in Na+ exclusion in the 40 ‘K51-40’ × ‘140 Ruggeri’ hybrids has previously been reported, with four unique alleles of this gene present in this family, with each parent heterozygous for a dominant allele (EK or ER) linked with strong exclusion and for a recessive allele (eK or eR) linked with poor exclusion. In the present study, we found ‘Schwarzmann’ is also heterozygous for HKT1;1 alleles, consisting of dominant (EK) and recessive (eK) alleles identical to those of ‘K51-40’. The 18 ‘K51-40’ × ‘Schwarzmann’ hybrids were scored for inheritance of these alleles. When screened for the Na+ exclusion phenotype, two homozygous eKeK genotypes accumulated less Na+ than eKeR hybrids having ‘140 Ruggeri’ as the pollen parent. Thus, it appears that the recessive eR allele from ‘140 Ruggeri’ results in higher Na+ accumulation than the recessive eK allele from ‘K51-40’ or ‘Schwarzmann’, and this is supported by functional Na+ transport rates of the encoded HKT1;1 proteins previously reported.

A link between the accumulation of sugar and potassium has previously been described for ripening grape berries. The functional basis of this link has, as of yet, not been elucidated but could potentially be associated with the integral role that potassium has in phloem transport. An experiment was conducted on Shiraz grapevines in a controlled environment. The accumulation of berry sugar was curtailed by reducing the leaf photoassimilation rate, and the availability of potassium was increased through soil fertilization. The study characterizes the relationship between the accumulation of sugar and potassium into the grape berry and describes how their accumulation patterns are related to the expression patterns of their transporter proteins. A strong connection was observed between the accumulation of sugar and potassium in the grape berry pericarp, irrespective of the treatment. The relative expression of proteins associated with sugar and potassium transport across the tonoplast and plasma membrane was closely correlated, suggesting transcriptional coregulation leading to the simultaneous translocation and storage of potassium and sugar in the grape berry cell.

Continuous-cropping leads to obstacles in crop productivity by the accumulation of p-hydroxybenzoic acid (PHBA) and ferulic acid (FA). In this study, a strain CFA of Pseudomonas was shown to have a higher PHBA- and FA-degrading ability in media and soil and the mechanisms underlying this were explored. Optimal conditions for PHBA and FA degradation by CFA were 0.2 g/l of PHBA and FA, 37°C, and pH 6.56. Using transcriptome analysis, complete pathways that converted PHBA and FA to acetyl coenzyme A were proposed in CFA. When CFA was provided with PHBA and FA, we observed upregulation of genes in the pathways and detected intermediate metabolites including vanillin, vanillic acid, and protocatechuic acid. Moreover, 4-hydroxybenzoate 3-monooxygenase and vanillate O-demethylase were rate-limiting enzymes by gene overexpression. Knockouts of small non-coding RNA (sRNA) genes, including sRNA 11, sRNA 14, sRNA 20, and sRNA 60, improved the degradation of PHBA and FA. When applied to cucumber-planted soil supplemented with PHBA and FA, CFA decreased PHBA and FA in soil. Furthermore, a reduction of superoxide radical, hydrogen peroxide, and malondialdehyde in cucumber was observed by activating superoxide dismutase, catalase, glutathione peroxidase, ascorbate peroxidase, glutathione reductase, dehydroascorbate reductase, and monodehydroascorbate reductase in seedlings, increasing the reduced glutathione and ascorbate in leaves, and inducing catalase, urease, and phosphatase in the rhizosphere. CFA has potential to mitigate PHBA and FA stresses in cucumber and alleviate continuous-cropping obstacles.

Whole-vine transpiration was estimated for well-watered nine-year-old Sultana grapevines (Vitis vinifera L. cv. Sultana) from xylem sap flow measured with Granier's heat-dissipation probes. Canopy conductance of the grapevine was calculated by inverting the Penman–Monteith equation. Transpiration from grapevine canopies was strongly controlled by the canopy conductance. Canopy conductance decreased exponentially with increasing vapour pressure deficit (VPD) except in the morning when solar radiation was less than 200 W m–2 and the canopy conductance was predominantly limited by the solar radiation. A non-linear model of canopy conductance as a function of the solar radiation and VPD explained > 90% of the variation observed in canopy conductance. Under contrasting VPD conditions (daytime maximum of 3 kPa vs 8 kPa), grapevines were able to regulate their canopy conductance from 0.006 to 0.001 m s–1 to maintain a near constant transpiration. Whole-canopy transpiration calculated from modelled canopy conductance using the Penman–Monteith equation was highly correlated with the measured transpiration (sap flow) values over the range of 0–0.20 mm h–1 (R2 > 0.85). Cross-validation shows that these mechanistic models based on solar radiation and VPD provide good predictions of canopy conductance and transpiration under the conditions of the study.

A non-invasive plant phenotyping platform, GrowScreen-PaGe, was used to resolve the dynamics of shoot and root growth of the model cereal Brachypodium (Brachypodium distachyon Bd21-3) in response to the plant growth promoting (PGP) bacteria Azospirillum (Azospirillum brasilense Sp245). Inoculated Brachypodium plants had greater early vigor and higher P use efficiency than non-inoculated Brachypodium at low P and low temperature conditions. Root systems were imaged non-invasively at eight time points and data combined with leaf area, shoot biomass and nutrient content from destructive subsamples at 7, 14 and 21 days after inoculation (DAI). Azospirillum colonisation of roots improved Brachypodium shoot and, to a greater degree, root growth in three independent experiments. Inoculation promoted P use efficiency in shoots but not P concentration or uptake, despite increased total root length. Longer roots in inoculated plants arose from twofold faster branch root growth but slower axile root growth, detected at 11 DAI. Analysis of the spatio-temporal phenotypes indicated that the effects of Azospirillum inoculation increased as shoot P concentration declined, but the magnitude depended on the time after inoculation and growth rate of branch roots compared to axile roots. High throughput plant phenotyping platforms allow the details of plant-microorganism symbioses to be resolved, offering insights into the timing of changes in different tissues to allow molecular mechanisms to be determined.

The management of the fuzzy front end (FFE) phase of innovation is crucial to the ultimate success of new product and process initiatives. A critical challenge that teams face at this stage is dealing with equivocality – the extent to which project participants grapple with multiple, and plausibly conflicting, meanings and interpretations of the information available to them (Daft and Lengel, 1986; Weick, 1979). While initially, a certain level of equivocality is beneficial for enhancing teams’ creativity and preventing early closure, at some point it must be resolved in order for an idea to become a viable New Product Development (NPD) project. This study employs a social networks perspective to understand how different types of informal work-based relations and their structural properties affect equivocality on project teams in the FFE. In particular, it examines the structural effects of two types of social relations and their associated networks—those of technical-advice and friendship ties. The findings suggest that while high density in projects’ technical-advice network is likely to reduce equivocality, high density in projects’ friendship network is likely to increase it. More interestingly, having multiple members on projects who are highly central in the lab's technical-advice network tends to increase equivocality unless it is balanced with members who occupy positions of high centrality in the lab's friendship network. In addition to contributing to the scholarship on NPD, FFE, and social networks, the results offer managerial insights for deploying social networks in order to assemble NPD teams and structure the flows of communication on projects so as to resolve equivocality in the FFE.

Abiotic stresses, such as soil water deficit and high soil solution salts, can lead to negative impacts on crop growth, productivity and quality, impacting industry profitability. The first contact of the tree with these stresses is the root system, providing the possibility of improving tree resilience by rootstock choice. Identifying almond rootstock genotypes with high stress tolerance is, consequently, of high importance in enabling the Australian almond industry to cope with these environmental challenges. This study developed and tested a potential tool to screen genotypes for tolerance to abiotic stresses, using the response of relative growth rate (RGR) to water deficit or salinity stress. Seedling plants of six almond rootstock cultivars were randomly allocated into three treatments (control, drought or salinity stress) for two months in a glasshouse. Plants in the well-watered treatment were irrigated to the point of run-off daily. The drought treatment was imposed by adding 33% of evapotranspiration of well-watered plants daily. Plants in the salinity treatment were supplied with mixed chloride solution (3.3 dS m-1) to the point of run-off daily. Plants were harvested at three time points to calculate RGR. The percentage of RGR reduction in stressed plants, relative to the non-stressed plants, was calculated and used as an index of stress tolerance. Considerable variation for stress tolerance was found among the six almond rootstock genotypes, with some genotypes being able to maintain growth rates - whereas others stopped growing - under drought or salinity stress. The impacts of the drought treatment used were generally larger than those of salinity stress. The screening approach introduced in this study provides a relatively simple and robust method to compare rootstock genotypes, contributing to horticultural management decisions, whilst also being applicable to the generation of fundamental knowledge in this area.

To measure the effect of veterans’ preference on U.S. federal workforce quality, researchers have assessed whether military veterans advance in their federal careers at a different rate than nonveterans. This research, however, has produced mixed results. In research concerning recent employee cohorts, nonveterans outpace veterans’ advancement, implying that veterans’ preference lessens employee quality. In older cohorts, veterans and nonveterans advance comparably. The latter research, however, controls for employees’ entry positions, whereas research concerning recent cohorts does not do so, thus inhibiting direct comparison of results. To facilitate such comparisons, we controlled for veterans’ and nonveterans’ entry positions in a study of career advancement among all white-collar, U.S. executive branch workers entering employment from 1992 to 2013. In these recent cohorts, we find roughly equivalent rates of career advancement among veterans and nonveterans when controlling for entry positions. This finding holds when using grade or pay increases as measures of advancement.

Background and Aims Rooted leaves were used to analyse the salt exclusion phenotype in grapevines. Genotypes included rootstocks 140 Ruggeri and K51‐40 and cultivar Cabernet Sauvignon – respectively, good, poor and intermediate chloride excluders. Methods and Results We investigated the effect of short‐term salt treatment on the chloride, sodium and potassium concentration of organs and whole rooted leaves and the time course of chloride accumulation in salt‐treated, whole rooted leaves. The effect of Control and salt plus low and high nitrate concentration on chloride and nitrate concentration in organs was assessed. Salt treatment increased chloride and sodium concentration in all organs but had no effect on potassium concentration. The chloride concentration of whole rooted leaves and the sodium concentration of lamina and petiole were similar between salt‐treated rooted leaves of 140 Ruggeri and K51‐40; 140 Ruggeri accumulated more chloride in roots and less in leaf (petiole and lamina) than K51‐40. Roots of salt‐treated 140 Ruggeri and K51‐40 responded to higher external nitrate by decreasing chloride concentration and increasing nitrate concentration. Conclusions Restricted transport of chloride to the leaf and greater storage in roots is a feature of the chloride exclusion phenotype in rooted leaves. The short‐term capacity of 140 Ruggeri for chloride exclusion from the leaf was reduced in the salt plus high nitrate treatment. This was linked to higher nitrate and reduced chloride accumulation in roots. Significance of the Study The chloride exclusion phenotype in rooted leaves was shown to involve greater partitioning to roots and less to the leaf, rather than differences in net chloride accumulation by whole rooted leaves.

International audience; Context: Effective vineyard decision making at strategic and operational timescales requires consideration of many factors, including vineyard design and management options, exogenous factors that are outside of the decision maker's control such as climate/weather, and desired outcomes such as yield and grape composition attributes. Process-based models enable prediction of vineyard outcomes in response to different decisions and with respect to exogenous factors.Objective: We present a review of process-based models that can simulate both key vineyard outcomes and their sensitivity to decisions and exogenous factors, and highlight how these models can ‘bridge the gap’ between data and decisions.Methods: We assess the suitability of process-based models to water, canopy and nutrient management contexts using a conceptual systems framework.Results and Conclusions:Currently available process-based models are most advanced in terms of supporting decisions regarding water management, and least advanced regarding nutrient management. They are also better suited to support decisions with respect to yield, compared to grape composition attributes.Significance: This paper provides guidance to modelling practitioners regarding appropriate process-based models for a range of vineyard decision contexts and assists viticulturists and decision makers in understanding how these models can support decisions for improved outcomes.

Accumulation of p-hydroxybenzoic acid (PHBA) in soil causes autotoxicity stress in cucumber. When the stress is mitigated by PHBA-degrading bacteria, plant metabolites have not been detected. To explore mechanisms underlining the mitigation, plant metabolites have not been combined with rhizospheric microbes, antioxidant and soil enzymes. In this study, a strain P620 of Klebsiella decomposed PHBA to acetyl CoA. Cucumber was sown into soil supplemented with P620 and/or PHBA. After addition with P620, P620 colonization and the enriched bacterial genera were observed in rhizosphere. Compared to PHBA stress alone, the combination of P620 application and PHBA stress improved plant growth, decreased PHBA concentration in soil, and increased the activities of five soil enzymes and eight antioxidant enzymes in leaves. Metabolomic and transcriptomic analysis highlighted that P620 application decreased the intensities of MAG(18:3) isomer 4, MAG(18:3) isomer 2, lysoPC 18:3 (2n isomer), 2'-deoxyadenosine-5'-monophosphate, pyridoxine, and glucarate O-phosphoric acid in PHBA-stressed leaves and down-regulated the expression of genes related to these metabolites. We propose a mechanism that P620 application alters microbial communities in PHBA-contaminated soil. Thus, the application reduces PHBA concentration in soil, activates antioxidant and soil enzymes, and also influences metabolites in leaves by affecting plant transcriptome, mitigating PHBA stress in cucumber.

Summary Under salinity, Vitis spp. rootstocks can mediate salt (NaCl) exclusion from grafted V. vinifera scions enabling higher grapevine yields and production of superior wines with lower salt content. Until now, the genetic and mechanistic elements controlling sodium (Na+) exclusion in grapevine were unknown. Using a cross between two Vitis interspecific hybrid rootstocks, we mapped a dominant quantitative trait locus (QTL) associated with leaf Na+ exclusion (NaE) under salinity stress. The NaE locus encodes six high-affinity potassium transporters (HKT). Transcript profiling and functional characterization in heterologous systems identified VisHKT1;1 as the best candidate gene for controlling leaf Na+ exclusion. We characterized four proteins encoded by unique VisHKT1;1 alleles from the parents, and revealed that the dominant HKT variants exhibit greater Na+ conductance with less rectification than the recessive variants. Mutagenesis of VisHKT1;1 and TaHKT1.5-D from bread wheat, demonstrated that charged amino acid residues in the eighth predicted transmembrane domain of HKT proteins reduces inward Na+ conductance, and causes inward rectification of Na+ transport. The origin of the recessive VisHKT1;1 alleles was traced to V. champinii and V. rupestris. We propose that the genetic and functional data presented here will assist with breeding Na+-tolerant grapevine rootstocks.

To assess the robustness of the apparent sugar-potassium relationship during ripening of grape berries, a controlled-environment study was conducted on Shiraz vines involving ambient and reduced (by 34%) atmospheric CO2 concentrations, and standard and increased (by 67%) soil potassium applications from prior to the onset of ripening. The leaf net photoassimilation rate was decreased by 35% in the reduced CO2 treatment. The reduction in CO2 delayed the onset of ripening, but at harvest the sugar content of the berry pericarp was similar to that of plants grown in ambient conditions. The potassium content of the berry pericarp in the reduced CO2 treatment was however higher than for the ambient CO2. Berry potassium, sugar and water content were strongly correlated, regardless of treatments, alluding to a ternary link during ripening. Root starch content was lower under reduced CO2 conditions, and therefore likely acted as a source of carbohydrates during berry ripening. Root carbohydrate reserve replenishment could also have been moderated under reduced CO2 at the expense of berry ripening. Given that root potassium concentration was less in the vines grown in the low CO2 atmosphere, these results point toward whole-plant fine-tuning of carbohydrate and potassium partitioning aimed at optimising fruit ripening.

Background and Aims The effect of season and deficit irrigation treatments was monitored on berry development and composition, yield and wine composition of Vitis vinifera L. cv. Cabernet Sauvignon grown in a hot climate during 2003–2005. Methods and Results The treatments were regulated deficit irrigation (RDI) and prolonged deficit irrigation (PD), compared with a standard industry irrigation (Control) treatment. Compared to the Control, RDI berries were smaller from a reduction in mesocarp (flesh) rather than in exocarp (skin) or seed mass but insufficient to significantly impact on yield. The PD treatment reduced berry size driven by mesocarp reduction resulting in a lower yield. Season 2005 had a significantly larger yield, mainly as a result of increased berry fresh mass, exocarp and seed mass compared to that of either 2003 or 2004. Grape juice TSS and pH were not significantly affected by water deficit, but each varied between seasons. The malic acid concentration of grape juice was reduced by the RDI and PD treatments, resulting in enhancement of the tartaric : malic acid ratio. Grape anthocyanin at harvest was unaffected by irrigation treatment but significantly impacted by season. Wine colour density, anthocyanin, ionised anthocyanin and phenolic substances were increased by RDI and PD and impacted by season. Conclusions Wine attributes were improved further by PD relative to RDI. Seasonal effects were shown to have an impact greater than the within-season water deficit treatments on most aspects of berry development and composition. Significance of the Study The study has demonstrated the utility of the PD treatment as an irrigation tool, where water availability is significantly limited and/or where improved spectral properties are required for wines.

Background and Aims: Exposure to salinity or water deficit is known to increase the concentration of abscisic acid (ABA) within grapevines. Elevated plant ABA has alone been shown to reduce the flux of chloride from roots to shoots. The aim was to evaluate the effect of exogenously applied ABA to grapevine root systems, with or without saline irrigation water, on water relations and ion allocation. Methods and Results: Vitis vinifera (Shiraz, clone EVOVS12) vines on own roots were treated with a control of nutrient solution only, and with other treatments, also in nutrient solution, consisting of 75 mmol/L chloride (Cl−) salts [cations: 45 mmol/L sodium (Na+), 7.5 mmol/L calcium (Ca++), 7.5 mmol/L magnesium (Mg++)], 50 and 100 μmol/L ABA, and 75 mmol/L Cl− salts plus 50 and 100 μmol/L ABA, all applied by watering to roots of potted vines in a glasshouse. Treatments were applied for 14 days before the plants were destructively harvested for ion analysis. All applied treatments reduced stomatal conductance, assimilation and transpiration, but ABA plus Cl− salts did not result in further reduction compared with that of ABA alone. Abscisic acid, only in the presence of salt, reduced Cl− concentration in all vine structures except the roots, while the concentration of Na+, K+ and Ca++ was less affected. This reduction could not be accounted for by reduced transpiration. Conclusion: In the presence of excess Cl− salts, ABA applied exogenously to Shiraz roots reduced Cl− transport to the shoot. Significance of Study: This provides some insight into the ability of deficit irrigation techniques to modify water relations and ion concentration.

Vine nutrition is a key element of vineyard management. Nutrient disorders affect vine growth, crop yield, berry composition, and wine quality. Each vineyard may have a unique combination of soil type, vine age, canopy architecture, cultivar and rootstock. Therefore nutritional requirements vary between vineyards and even locations within a vineyard. Nutritional disorders can be detected visually on leaves, fruits, stems or roots. The advancement of image processing and machine learning has made it feasible to develop rapid tools to assess vine nutritional disorders using these symptoms. This paper presents our proposed method of using a smartphone app to capture and analyse images of vine leaves for identifying nutritional disorders of grapevines rapidly and conveniently. Nutrient deficiency/toxicity symptoms were created in hydroponically grown grapevines of both red and white varieties. RGB (red, green, and blue) images of old and young leaves were taken weekly to track the progression of symptoms. A benchmarked dataset was developed through a laboratory based nutrient analysis of the petioles. A wide range of features (e.g., texture, smoothness, contrast and shape) were selected for the following customised machine learning techniques. Our proposed algorithm was developed to identify specific deficiency and toxicity symptoms through training and testing process. The support vector machine has achieved a 98.99% average accuracy in the testing.

Background and Aims Deficit irrigation techniques have been used to improve water use efficiency and control vigour in grapevines, but the consequences of using saline water with these techniques have been little investigated. Here, we investigate the effect of deficit irrigation with moderately saline water on within-vine ion allocation. Methods and Results Drip-irrigated own-rooted Shiraz and Grenache vines grown in pots were subjected to control, reduced control and partial root-zone drying (both approximately 50% less than control) irrigation treatments utilising moderately saline irrigation (mean of 2.46 dS/m) over two seasons. Plant water status and stomatal conductance were measured during the growing seasons, and at the end of the second season, the vines were destructively sampled to determine plant growth and concentration of ions of various vine structures. When compared against the control, partial root-zone drying had a higher total concentration of Cl−, Na+, K+ and Ca++ present on a whole vine basis. Although Cl− concentration was elevated in leaves for the partial root-zone drying treatment, it was partitioned away from leaves on a total content basis relative to both control and reduced control treatments. The partial root-zone drying treatment also resulted in significantly lower midday leaf water potential. Conclusion Ion partitioning within grapevines depends on the type of deficit applied. Significance of the Study Utilising deficit irrigation techniques in combination with saline irrigation water will alter the allocation of ions within a grapevine highlighting the importance of monitoring during the growing season for both fruit composition and long-term vine health.

Grapevine (Vitis vinifera L.) is a valuable crop for human consumption and wine production, and is prone to suffering from salinity stress in arid regions or when exposed to low quality irrigation water. A previous study identified a quantitative trait locus (QTL) NaE, containing six High-affinity Potassium Transporter 1 genes, that was associated with shoot Na+ exclusion in grapevine. While HKT1;1 was predicted to be the most likely gene within this QTL to encode for this important salinity tolerance sub-trait, four other HKTs within the QTL remained uncharacterised; VviHKT1;2 encodes a truncated transcript unlikely to form a functional transporter. In this study, two allelic variants for each of VviHKT1;6, VviHKT1;7 and VviHKT1;8 from the heterozygous grapevine variety Cabernet Sauvignon were functionally characterised. Using the Xenopus laevis oocyte heterologous expression system, as well as transient expression in tobacco leaves, we found that the VviHKT1;6 and VviHKT1;7 alleles encoded plasma membrane localised proteins that facilitated significant non-rectifying Na+ transport. Conversely, proteins encoded by the VviHKT1;8 alleles were inwardly-rectifying, weak Na+ transporters that localised to intracellular organelles. Mining of previous RNA-seq gene expression data suggested that VviHKT1;6-8 are weakly expressed in grapevine roots, flower buds, and seeds under normal conditions and different nutrient regimes. We propose that VviHKT1;6 and VviHKT1;7 are likely to have a less significant role in grapevine leaf Na+ exclusion than VviHKT1;1, and that VviHKT1;8 is involved in endomembrane Na+ transport.

As agriculture and food security face unprecedented challenges, emerging agricultural innovations and existing practices require ongoing examination in the context of sustainability. In this review, we focus on the use of probiotic microorganisms for improved plant production. As plants are enormously diverse, emphasis is placed on the fundamental sites of plant-microbe interactions regarding benefits and challenges encountered when altering the microbiome of these locations. The soil, the external plant epidermis, and internal plant tissue are considered in discussion regarding the type of plant probiotic application. Plant probiotics range from broader soil beneficial microorganisms (such as Trichoderma spp.) through to specialised epiphytes and endophytes (such as root nodule bacteria). As each site of interaction affects plant growth differently, potential outcomes from the introduction of these exogenous microorganisms are discussed with regard to plant productivity. Finally, recommendations regarding regulation and future use of plant probiotics are points of consideration throughout this review.

This paper introduces GRover (the grapevine rover), an adaptable mobile platform for the deployment and testing of proximal imaging sensors in vineyards for the non-destructive assessment of trunk and cordon volume and pruning weight. A SICK LMS-400 light detection and ranging (LiDAR) radar mounted on GRover was capable of producing precise (±3 mm) 3D point clouds of vine rows. Vineyard scans of the grapevine variety Shiraz grown under different management systems at two separate locations have demonstrated that GRover is able to successfully reproduce a variety of vine structures. Correlations of pruning weight and vine wood (trunk and cordon) volume with LiDAR scans have resulted in high coefficients of determination (R2 = 0.91 for pruning weight; 0.76 for wood volume). This is the first time that a LiDAR of this type has been extensively tested in vineyards. Its high scanning rate, eye safe laser and ability to distinguish tissue types make it an appealing option for further development to offer breeders, and potentially growers, quantified measurements of traits that otherwise would be difficult to determine., This project was partly funded by Australia’s grape growers and winemakers through their investment body Wine Australia with matching funds from the Australian Federal Government. Additional funds for this work were provided by Commonwealth Scientific and Industrial Research Organisation (CSIRO).

Background and Aims We investigated rootstock effects on the response of fruit and wine composition to reduced irrigation in vines growing on saline soil. Methods and Results Drip-irrigated Shiraz vines on five rootstocks were subjected to industry standard and 30% reduced irrigation over four consecutive seasons. Fruit composition during berry shrivel and at harvest was assessed in each season and wine was made and assessed in two seasons. Rootstock and irrigation independently affected fruit anthocyanins concentration and wine spectral properties. In two seasons, reduced irrigation affected the accumulation of anthocyanins and total soluble solids during berry shrivel. Fruit from 110 Richter had a 16% higher concentration of anthocyanins and wine a 29% higher colour density than that of fruit and wine from Ramsey. Sodium and chloride concentration in wine from 110 Richter was 27 and 50% less than in wine from Ramsey. In one of two seasons, reducing irrigation improved the sensory score from wines on 110 Richter and 140 Ruggeri rootstocks. Yield and berry mass accounted for 25% and less than 1%, respectively, of the variation in concentration of fruit anthocyanins over four seasons. Conclusion Reducing irrigation and substitution of 110 Richter for Ramsey rootstock both improved fruit composition, but reduced yield. In the early 2000s, the extra payment for higher quality did not offset the loss due to lower yield. Significance of the Study Wine from vines on 110 Richter had higher colour and a lower concentration of sodium and chloride than that wine from vines on Ramsey.

Background and Aims This study investigated the response of field-grown Shiraz vines to saline irrigation involving water-deficit irrigation techniques. Methods and Results Drip-irrigated Shiraz vines were subjected to control (1.0–2.3 ML/ha), reduced control and partial root zone drying (both approximately 50% less than control) irrigation treatments utilising moderately saline irrigation over three seasons. Grape juice chloride (Cl−) and sodium (Na+) concentration was not affected significantly by irrigation treatment, although it did vary greatly between seasons. Seasonal influence of rainfall was shown to have more of an effect on Na+ concentration in grape juice, while irrigation applied and hence overall salt load impacted more heavily on grape juice Cl−. Partial root zone drying when compared against the controls had reduced stomatal conductance, leaf water potential, berry mass, and yield and pruning mass, while there was no significant effect on TSS (°Brix), pH and titratable acidity. Conclusion In this study, the seasonal variation of rainfall and total irrigation applied played a greater role in altering the concentration of grape juice Cl− and Na+ than the application of irrigation water with the same moderate salinity but with the differing irrigation strategies. Significance of the Study Regions, where water allocation has been reduced and which are relying on a saline irrigation source, have the ability to manage the Cl− and Na+ concentration present in grape juice by having a better understanding of the role season can play and the variability within that season, thereby making more informed decisions on when to apply irrigation.

Under salinity, Vitis spp. rootstocks can mediate salt (NaCl) exclusion from grafted V. vinifera scions enabling higher grapevine yields and production of superior wines with lower salt content. Until now, the genetic and mechanistic elements controlling sodium (Na

To assess the robustness of the apparent sugar-potassium relationship during ripening of grape berries, a controlled-environment study was conducted on Shiraz vines involving ambient and reduced (by 34%) atmospheric CO

Background and Aims The effect of rootstock on chloride (Cl−) and sodium (Na+) exclusion capacity and yield of Chardonnay and Shiraz was investigated in the final 2 years (2007/08 and 2008/09) of a long-term (14-year) saline irrigation trial. Methods and Results Chardonnay and Shiraz, on own roots and on nine rootstocks, were irrigated for the first 12 seasons with water of electrical conductivity (ECiw) of 2.1 dS/m, with 7.15 ML/ha the mean total applied. The final two seasons were years of water restrictions, where the vines were irrigated with water of (mean) ECiw of 1.65 dS/m at a seasonal application of 3.04 ML/ha. Vines on own roots had a relatively low yield, for example 2.0 kg/vine (Chardonnay) and 8.8 kg/vine (Shiraz), and a high concentration of both chloride and sodium in grape juice (>1000 mg/L for Chardonnay and >500 mg/L for Shiraz). Ramsey and 1103 Paulsen rootstocks produced a high yield of 11–12 kg/vine with Chardonnay, and Ramsey and C7 produced a high yield of 23.5–24.5 kg/vine with Shiraz. Chardonnay on C5 and Shiraz on C7 rootstocks had the lowest concentration of grape juice chloride and sodium (in each case 10 years) study to compare the effect of rootstocks on the tolerance of Chardonnay and Shiraz to salinity.

Soils in some major Australian viticultural regions are generally high in potassium content, which is in contrast to viticultural regions in other parts of the world. There is a considerable body of evidence, both from commercial experiences and research results, that the widely adopted high vigour, root-knot nematode tolerant rootstock varieties contribute to negative impacts on wine quality associated with high potassium uptake, high pH and malate levels. Previous findings have shown that in a given year, grafted vine grape juice pH at harvest is highly correlated with the ungrafted rootstock petiole potassium level at anthesis. We demonstrated that this relationship is also present when multiple years of juice pH and ungrafted rootstocks petioles are compared. The mean harvest pH of ?Chardonnay? grafted on 6 commer¬cial rootstocks from 4 vineyards over two consecutive years had a strong correlation (adjusted R2= 0.755) with the 2 year mean potassium content of the ungrafted rootstocks in the field. Likewise, the 8 year mean pH of a rootstock trial with 5 commercial rootstock and 14 experimental rootstocks with ?Shiraz? scions was highly correlated (adjusted R2= 0.502) with the 2 year mean petiole potassium content of the ungrafted field grown rootstocks. To facilitate accelerated breeding of new rootstocks, we have developed a glasshouse based assay for the early selection of rootstocks with low potassium transport to aerial tissues. We demonstrated that the 8 year mean juice pH of grafted vines is also correlated with the ungrafted vine petiole potassium content for plants grown in the glasshouse with supplemented levels of potassium (adjusted R2= 0.501). In addition, we are also screening vines in the glasshouse for resistance to the root-knot nematode Meloidogyne javanica. We are currently screening potential and commercial germplasm for resistance to M. javanica, and have identified a Vitis cinerea accession that transmits resistance as a single dominant gene.

Introduction: Among all venous thromboembolism (VTE) events, 20% occur during or in the three months following a hospitalization. Inpatient VTE prevention strategies incorporate pharmacological interventions that do not commonly continue after discharge. Recent trials of post-discharge prophylaxis have not identified benefit among recently discharged patients, probably due to lack of understanding of the relative and absolute risks of VTE after discharge. In order to better clarify the scope of the problem, we quantified the risk of VTE during hospitalizations, and up to 3 months post-discharge relative to patients without a recent hospitalization. Methods: We followed all primary care patients aged ≥18, at the University of Vermont Medical Center's primary care clinics for hospitalization and VTE using the electronic medical record. Patients entered the cohort at their first contact with the health system after 06/30/2010 and were followed until their last contact, change of primary care provider to a non-University of Vermont provider, or December 2016, whichever occurred first. First VTE during follow-up was defined as having two outpatient VTE codes 7-185 days apart or one inpatient code. Patients with a VTE code in the first 3 months of enrollment were excluded as having pre-baseline VTE. Hospital-acquired VTE was defined as VTE occurring after day 1 of hospitalization (to correctly categorize people with an outpatient VTE and admitted with VTE) and post-discharge VTE was defined as VTE occurring during successive 1-month time periods after discharge from the hospital. Age- and sex-adjusted Cox proportional hazard models were used to calculate hazard ratios (HRs) of VTE during and after hospitalization. Hospitalization and time periods after hospitalization were modeled as time-varying covariates and included the time in the hospital, and 1-30 (month 1), 31-60 (month 2), and 61-90 (month 3) days post-discharge. The reference group for this analysis was outpatients who were not within 90 days of a hospitalization. Results: From 2010-16, 87,821 patients (49,468 women, 56%) were included, with a mean age of 46 years. With 371,429 person-years of follow-up (mean follow-up 4.2 years), 749 first VTE events occurred for a rate of 2.0 per 1,000 person-years. There were 57,837 hospitalizations among 21,963 individuals for a rate 155.7 hospitalizations per 1,000 person-years. The Table presents the person-years of follow-up, the number, rate, and age- and sex-adjusted hazard of VTE for hospitalization and successive months after hospitalization. The VTE rate was 1.5 per 1,000 person-years outpatients not within 3 months of hospitalization. During hospitalization, the rate was 75.9 per 1,000 person-years, and slowly decreased over time after discharge, but remained elevated at 5.0 per 1,000 person-years event in month 3 after discharge. The age- and sex-adjusted HR for VTE was 40.3 during hospitalization and declined to 18.1, 6.0 and 2.9 over successive 1-month intervals after discharge (Table). Conclusion: In a primary care population in northern Vermont, hospitalization and time periods after hospitalization were associated with a dramatically increased incidence of and risk for VTE compared with patients not hospitalized in the past 3 months. The rate of VTE (34.4 per 1,000 person-years) in the first month post-discharge might not warrant universal post-discharge VTE prophylaxis, but suggests that if we can identify high-risk patients at low risk for bleeding, pharmacologic VTE prophylaxis may be appropriate in some patients. Further study of risk factors for post-discharge VTE is warranted. Table Disclosures No relevant conflicts of interest to declare.

Burkholderia sp. strain WSM2230 is an aerobic, motile, Gram-negative, non-spore-forming acid-tolerant rod isolated from acidic soil collected in 2001 from Karijini National Park, Western Australia, using Kennedia coccinea (Coral Vine) as a host. WSM2230 was initially effective in nitrogen-fixation with K. coccinea, but subsequently lost symbiotic competence. Here we describe the features of Burkholderia sp. strain WSM2230, together with genome sequence information and its annotation. The 6,309,801 bp high-quality-draft genome is arranged into 33 scaffolds of 33 contigs containing 5,590 protein-coding genes and 63 RNA-only encoding genes. The genome sequence of WSM2230 failed to identify nodulation genes and provides an explanation for the observed failure of the laboratory grown strain to nodulate. The genome of this strain is one of 100 sequenced as part of the DOE Joint Genome Institute 2010 Genomic Encyclopedia for Bacteria and Archaea-Root Nodule Bacteria (GEBA-RNB) project.

Burkholderia sp. strain WSM2232 is an aerobic, motile, Gram-negative, non-spore-forming acid-tolerant rod that was trapped in 2001 from acidic soil collected from Karijini National Park (Australia) using Gastrolobium capitatum as a host. WSM2232 was effective in nitrogen fixation with G. capitatum but subsequently lost symbiotic competence during long-term storage. Here we describe the features of Burkholderia sp. strain WSM2232, together with genome sequence information and its annotation. The 7,208,311 bp standard-draft genome is arranged into 72 scaffolds of 72 contigs containing 6,322 protein-coding genes and 61 RNA-only encoding genes. The loss of symbiotic capability can now be attributed to the loss of nodulation and nitrogen fixation genes from the genome. This rhizobial genome is one of 100 sequenced as part of the DOE Joint Genome Institute 2010 Genomic Encyclopedia for Bacteria and Archaea-Root Nodule Bacteria (GEBA-RNB) project.

This article evaluates two alternative standards for resetting property assessments on title transfer in property tax systems like Oregon’s and California’s, which are explicitly designed to protect property owners against rapid, unanticipated increases in their tax bills: California’s reset to market and one in which the property is given a new assessed value based on its market value and a ratio that is updated annually to reflect the average relationship between assessed value and market value within a jurisdiction. We find that the latter promotes assessment quality better than the former and also probably mitigates lock-in.

Research suggests that outsourcing is one way that local governments have to meet rising expectations and unwillingness to pay when resources are constrained. The degree to which resources are constrained is a function not only of local economic and political conditions, but of state rules as well. We build on previous models of local government outsourcing by studying the interaction between state rules and local fiscal, economic, and political conditions. We find that cities in states that place limits on the resources available to local governments choose differently from among the constellation of service provision options than cities in states without such limits. Copyright , Oxford University Press.

One of the central claims of public administration is that management matters for the performance of public entities. Quantifying the impact of organizational management is thus central to the empirical evaluation of this claim. Utilizing novel features of the Government Performance Project (GPP), we assess the impact of state-level management practices on the credit quality of US states. The central challenge—that both the GPP data and bond ratings take the form of ordinal grades—suggests a common solution utilizing multiple indicators of a latent construct (management capacity and credit quality) with appropriate measurement models. After describing the characteristics of the measurement approach, we derive management capacity scores from the GPP data and credit quality scores using bond ratings from the three rating agencies. These derived scores then allow us to test linkages between credit quality of the US states and broad aspects of their relative management capacity. On the whole, we show that financial management capacity influences credit quality, while the evidence is less clear that other forms of management capacity matter.

Potted grapevines of 140 Ruggeri (Vitis berlandieri × Vitis rupestris), a good Cl(-) excluder, and K 51-40 (Vitis champinii × Vitis riparia 'Gloire'), a poor Cl(-) excluder, and of a family obtained by crossing the two genotypes, were used to examine the inheritance of Cl(-) exclusion. Rooted leaves were then used to further investigate the mechanism for Cl(-) exclusion in 140 Ruggeri. In both a potting mix trial (plants watered with 50 mM Cl(-)) and a solution culture trial (plants grown in 25 mM Cl(-)), the variation in Cl(-) accumulation was continuous, indicating multiple rather than single gene control for Cl(-) exclusion between hybrids within the family. Upper limits of 42% and 35% of the phenotypic variation in Cl(-) concentration could be attributed to heritable sources in the potting mix and solution culture trials, respectively. Chloride transport in roots of rooted leaves of both genotypes appeared to be via the symplastic pathway, since addition of 8-hydroxy-1,3,6-pyrenetrisulphonic acid (PTS), an apoplastic tracer, revealed no obvious PTS fluorescence in the laminae of either genotype, despite significant accumulation of Cl(-) in laminae of K 51-40 during the PTS uptake period. There was no significant difference in either unidirectional (36)Cl(-) flux (10 min) or (36)Cl(-) uptake (3 h) into roots of rooted leaves exposed to 5, 10, or 25 mM Cl(-). However, the percentage of (36)Cl(-) transported to the lamina (3 h) was significantly lower in 140 Ruggeri than in K 51-40, supporting reduced Cl(-) loading into xylem and implicating the root stele in the Cl(-) exclusion mechanism.

Background and Aims: The study investigated whether rootstocks can modify grapevine responses to reduced irrigation. Methods and Results: Drip-irrigated Shiraz vines on eight rootstocks were subjected to industry standard and 30% reduced irrigation regimes over four seasons. Reducing irrigation decreased pruning weights and yield, but did not consistently affect irrigation water use index (IWUI). It increased leaf Δ13C. Reduced irrigation and elevated vapour pressure deficit (VPD) were associated with decreases in leaf water potential (ψl), leaf stomatal conductance and assimilation rate. Reducing irrigation raised leaf transpiration efficiency, whereas elevated VPD lowered it. These effects of reduced irrigation were independent of rootstock. Vines grafted to 101-14 had a higher ψl and achieved the highest yield and IWUI. The yields of vines grafted to Ramsey, Schwarzmann and 140 Ruggeri were also high. Vines grafted to 101-14, Ramsey and 1103 Paulsen had the higher rates of leaf assimilation. Rootstock did not affect Δ13C. Conclusion: The gain in leaf transpiration efficiency caused by reducing irrigation was not associated with a gain in IWUI. Rootstocks 101-14, Ramsey, Schwarzmann and 140 Ruggeri achieved higher yields and IWUI under both standard and reduced irrigation regimes. Significance of the Study: Among grafted vines growing on saline soil but receiving non-saline irrigation water and subject to a 30% reduction in irrigation, the yield responses of vines grafted on rootstocks rated as having good drought tolerance were the same as those of vines grafted on rootstocks rated as having poor drought tolerance.

Water use efficiency (WUE) and response of grape vines (Vitis vinifera L. cvs. ‘Cabernet Sauvignon’, ‘Merlot’, and ‘Viognier’) to a particle film treatment (PFT) under varying levels of applied water were evaluated in Victoria, Australia, and southwestern Idaho. Vines that received the least amount of water had the warmest canopy or leaf surface temperature and the lowest (more negative) leaf water potential, stomatal conductance (gS), transpiration (E), and photosynthesis (A). Vines with plus-PFT had cooler leaf and canopy temperature than non-PFT vines; however, temperature difference resulting from irrigation was greater than that resulting from PFT. In well-watered vines, particle film application increased leaf water potential and lowered gS. Point-in-time measurements of WUE (A/E) and gS did not consistently correspond with seasonal estimates of WUE based on carbon isotope discrimination of leaf or shoot tissue. The response of vines with particle film to undergo stomatal closure and increase leaf water potential conserved water and enhanced WUE under non-limiting soil moisture conditions and the magnitude of response differed according to cultivar.

Background and Aims: Within-site comparisons were made of rootstock effects on yield, and chloride and sodium concentrations in petioles, juice and wine of Shiraz and Chardonnay vines at sites with irrigation water salinities (ECiw) ranging from low (0.4 dS/m) to moderate-high (1.8 to 3.3 dS/m). It also compared consistency of yield performance of the various rootstocks with both scions over 8 years at one site with an ECiw of 2.1 dS/m. Methods and Results: Chardonnay and Shiraz on own roots and on Ramsey, 1103 Paulsen, 140 Ruggeri, K51-40, Schwarzmann, 101-14, Rupestris St. George and 1202 Couderc were compared. Ramsey resulted in better yields relative to most of the other rootstocks at three of the four sites for each scion. Exceptions were the low salinity site where Schwarzmann was best with Chardonnay, and Padthaway where 140 Ruggeri was best with Shiraz. Chardonnay wine chloride concentrations were similar to grape juice chloride concentrations, but Shiraz wine chloride concentrations were on average 1.7-fold higher than grape juice chloride. Conclusions: Shiraz on own roots, K51-40 and 1202C rootstocks carry some risk of accumulating unacceptable levels of chloride in grape juice and wine when the salinity of the irrigation water is at moderate to high levels. Rootstocks K51-40 (with Chardonnay and Shiraz) and potentially 101-14 (with Shiraz) should be avoided in situations of long term irrigation with moderate to high salinity water. Significance of the Study: The study identifies rootstocks with acceptable yields and grape juice chloride concentrations for potential use in regions affected by salinity.