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Barley is a resilient crop that performs better than other cereal plants under abiotic stress conditions, including salinity stress. The understanding of salinity tolerance in crops is a major milestone to increase yield in areas affected by soil salinity. In barley, some components of salinity tolerance have been elucidated, (e.g. HVP10, which is involved in tissue tolerance), yet little research has explored the discovery of other components contributing to salinity tolerance. In this PhD project, a forward genetics approach was used, whereby two barley populations were phenotyped under controlled and field conditions for salinity tolerance. The first population is a diversity panel of two-row European spring barley, and the second population is a nested association mapping barley population with wild donors from the Fertile Crescent. The use of non-destructive high-throughput experiments conducted under controlled conditions provided insight into the understudied shoot ion-independent component of salinity tolerance. In addition, the previously known association HvHKT1;5 was detected under controlled conditions. In parallel, the field experiments increased our understanding of new components of salinity tolerance, such as the maintenance of yield and yield-related traits under saline conditions. This strategy was successful with the identification of a locus on chromosome 2H (140-145 cM), where the allele from one of the wild donors of the nested association mapping population increased yield under saline conditions in the field. When re-evaluating lines homozygous at the 2H locus, ear length, ear number per plant, yield and harvest index were all significantly higher under saline conditions for the lines carrying the wild allele. Furthermore, another interesting locus on chromosome 7H that was responsive to salt treatment and co-localized with HVP1 was identified using the diversity panel population. Loci with known flowering genes were also shown to be involved in salinity tolerance. To conclude, this PhD project shed more light on the genetic mechanisms of salinity tolerance in barley, a knowledge that can benefit breeding programs and can be extended to other crops such as wheat.

CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / O dimensionamento de fundaÃÃes superficiais requer definiÃÃo de forma clara e objetiva, para o solo em estudo, da capacidade de carga e a previsÃo dos recalques a que se submete a estrutura, baseando-se nas propriedades mecÃnicas obtidas por ensaios de laboratÃrio e campo. O ensaio de placa à uma das formas mais seguras para se obter essas informaÃÃes, a partir de carregamento direto, que produz, em escala reduzida, o comportamento da futura fundaÃÃo. Os ensaios realizados nesta pesquisa foram executados em trÃs etapas: caracterizaÃÃo geotÃcnica (granulometria, determinaÃÃo da massa especÃfica, limite de consistÃncia, compactaÃÃo proctor normal e Ãndice de suporte califÃrnia (ISC)); ensaios especiais de laboratÃrio (adensamento e cisalhamento); e ensaios de campo (provas de carga). O objetivo deste trabalho à avaliar a partir da realizaÃÃo de provas de carga diretas com solo na umidade natural e inundado, se previsÃes de potencial de colapso e expansÃo, realizadas a partir de ensaios edomÃtricos simples e duplos sÃo capazes de dar indicaÃÃes concordantes. Foi observado que resultados de ensaios edometricos duplos, realizados no solo silto argiloso da cidade de IcÃ, proporcionaram estimativas mais concordantes para as situaÃÃes de colapso do solo. AlÃm disso, a tÃcnica da compactaÃÃo de solos problemÃticos se mostrou adequada para minorar, ou mesmo anular, problemas relacionados ao colapso e a expansÃo do solo estudado. / The design of shallow foundations requires defining clearly and objectively to the soil under study, the load capacity and the prediction of settlements that undergoes structure, based on the mechanical properties obtained from laboratory testing and field. The plaque assay is one of the safest ways to get this information from direct loading, which produces, in reduced scale, the behavior of the Future Foundation. The tests performed in this study were performed in three steps: geotechnical characterization (particle size, density determination, consistency limits, standard Proctor compaction and California bearing ratio (ISC)​​); Special laboratory tests (density and shear); and field trials (load tests). The objective of this study is to evaluate the evidence from conducting direct load with soil and flooded in natural moisture, if forecasts of potential collapse and expansion, made ​​from single and double edomÃtricos tests are able to give consistent evidence. It was observed that results of double edometricos trials, conducted in silty clay soil of the city Ico, provided more consistent estimates for situations of soil collapse. Furthermore, the technique of compression problematic soils was adequate to mitigate or even nullify, problems related to the collapse and expansion of the studied soil.

According to the community database on accidents on the roads in Europe, 2035 cyclist fatalities happened in Europe in 2019 [S]. In Sweden, 10440 bicycle crashes were reported in the Swedish Traffic Accident Data Acquisition database during 2019, and 30% of the cyclist fatalities were in car-to-cyclist rear-end crashes [6]. Nowadays, new micromobility vehicles (MMVs), for example, e-scooters, and Segways, are becoming more popular. Unlike traditional bicycles, these new MMVs usually have novel designs in appearance, kinematics, operation method, and power source (e.g., electricity-driven/assisted), which bring new hazards to traditional road users [1, 4]. Thus, it is essential to understand and quantify the behavior of the new MMV users to improve road safety.

A series of studies are presented on the genetic evaluation of cultivated potato (Solanum tuberosum L.) to improve the accuracy and efficiency of selection at various stages of a breeding programme. The central theme was the use of correlated data, such as relationship information and spatial and across-trial correlations, within a linear mixed modelling framework to enhance the evaluation of candidate genotypes and to improve the genetic response to selection. Analyses focused on several social and economically-important traits for the enhancement of the nutritional value, disease resistance and yield of potato tubers. At the formative stages of a breeding scheme, devising a breeding strategy requires an improved understanding of the genetic control of target traits for selection. To guide a strategy that aims to enhance the micronutrient content of potato tubers (biofortification), univariate and multivariate Bayesian models were developed to estimate genetic parameters for micronutrient tuber content from a breeding population generated from crosses between Andean landrace cultivars. The importance of the additive genetic components and extent of the narrow-sense heritability estimates indicated that genotypic 'individual' recurrent selection based on empirical breeding values rather than family-based selection is likely to be the most effective strategy in this breeding population. The magnitude of genetic correlations also indicated that simultaneous increases in important tuber minerals, iron and zinc, could be achieved. Optimising selection efficiency is an important ambition of plant breeding programmes. Reducing the level of candidate replication in field trials may, under certain circumstances, contribute to this aim. Empirical field data and computer simulations inferred that improved rates of genetic gain with p-rep (partially replicated) testing could be obtained compared with testing in fully replicated trials at the early selection stages, particularly when testing over two locations. P-rep testing was able to increase the intensity of selection and the distribution of candidate entries across locations to account for G×E effects was possible at an earlier stage than is currently practised. On the basis of these results, it was recommended that the full replication of trials (at the first opportunity, when enough planting material is available) at a single location in the early stages of selection should be replaced with the partial replication of selection candidates that are distributed over two locations. Genetic evaluation aims to identify genotypes with high empirical breeding values (EBVs) for selection as parents. Using mixed models, spatial parameters to target greater control of localised field heterogeneity were estimated and variance models to account for across-trial genetic heterogeneity were tested for the evaluation of soil-borne powdery scab disease and tuber yield traits at the early stages of a selection programme. When spatial effects improved model fit, spatial correlations for rows and columns were mostly small for powdery scab, and often small and negative for marketable and total tuber yield suggesting the presence of interplot competition in some years for tuber yield traits. For the evaluation of powdery scab, genetic variance structures were tested using data from 12 years of long-term potato breeding METs (multi-environment trials). A simple homogeneous correlation model for the genetic effects was preferred over a more complex factor analytic (FA) model. Similarly, for the MET evaluation of tuber yield at the early stages, there was little benefit in using more complex FA models, with simple correlation structures generally the most favourable models fitted. The use of less complex models will be more straightforward for routine implementation of potato genetic evaluations in breeding programmes. Evaluations for (marketable) tuber yield were extended to multi-location MET data to characterise both genotypes and environments, allowing a re-evaluation of New Zealand MET selection strategies aimed at broad adaptation. Using a factor analytic mixed model, results indicated that the programme’s two main trial locations in the North and the South Islands optimised differentiation between genotypes in terms of G×E effects. There was reasonable performance stability of genotypes across test locations and evidence was presented for some, but limited, genetic progress of cultivars and advanced clonal selections for tuber marketable yield in New Zealand over recent years. The models and selection strategies investigated and developed in this thesis will allow an improved and more systematic application of genetic evaluations in potato selection schemes. This will provide the basis for well informed decisions to be made on selection candidates for the genetic improvement of potato in breeding programmes.

Integrated Pest Management (IPM) has long been promoted as a means of reducing reliance on pesticide inputs as compared to conventional farming systems. Reduced pesticide application could be beneficial due to the links between intensive pesticide use and negative impacts upon biodiversity and human health as well as the development of pesticide resistance. Work assessing the potential of IPM in cereal production is currently limited, however, and previous findings have generally covered the subject from the perspective of either field trial data or social science studies of farmer behaviour. This thesis attempts to help to address this knowledge gap by providing a more holistic assessment of IPM in Scottish spring barley production (selected because of its dominance in Scotland’s arable production systems), in relation to three of its most damaging fungal pathogens: Rhynchosporium commune, Blumeria graminis f.sp. hordei, and Ramularia collo-cygni. Several IPM techniques of potential relevance to the sector were identified, and the prospects of three in particular – crop rotation, varietal disease resistance, and forecasting disease pressure – were assessed in several ways. Preliminary analysis of experimental field trial data collected from 2011 – 2014 across Scotland found that the majority of spring barley trials in this period (65%) did not show a statistically significant impact of fungicide treatment on yield, with the average yield increase due to fungicide application being 0.62 t/ha. This initial analysis was expanded upon using stepwise regressions of long-term (1996 – 2014) field trial data from the same dataset. Here, the difference between treated and untreated yields could be explained by disease resistance, average seasonal rainfall (whereby wetter seasons saw an increased impact of fungicide use on yield), and high combined disease severity. Stakeholder surveying provided information about current practice and attitudes towards the selected IPM techniques amongst a group of 43 Scottish spring barley farmers and 36 agronomists. Stakeholders were broadly open to taking up IPM measures on farm; sowing of disease resistant varieties was most frequently selected as the best technique in terms of both practicality and cost, though individual preference varied. However, a disparity was seen between farmer perception of their uptake of IPM and actual, self-reported uptake for both varietal disease resistance and rotation. Farmers and agronomists also overestimated the impact of fungicide use as compared with the field trials results – the majority of stakeholders believed fungicide treatment to increase yields by 1 - 2 t/ha, while the majority of 2011 – 2014 field trials had a yield difference of under 1 t/ha. The reasons behind these differences between perception and practice are not currently known. Finally, an annual survey of commercial crops, gathered from 552 farms across Scotland (from 2009 – 2015), highlighted two gaps where IPM practice could be improved upon. Firstly, relatively few of the varieties listed in the commercial crops database were highly resistant to the three diseases – 26.1% were highly resistant to Ramularia, 14.2% to Rhynchosporium, and 58.1% to mildew. Secondly, 71% of the farms included in the database had planted barley in at least two consecutive seasons, indicating that crop rotation practices could be improved. The overarching finding of this project is that there is scope for IPM uptake to be improved upon and fungicide use to be reduced while maintaining high levels of yield in Scottish spring barley production. Incorporating experimental field data, stakeholder surveying, and commercial practice data offered a unique view into the potential for IPM in this sector, and provided insights which could not have been gained through the lens of a single discipline.