74 research outputs found

    Environmental Response and Genomic Regions Correlated with Rice Root Growth and Yield under Drought in the OryzaSNP Panel across Multiple Study Systems

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    The rapid progress in rice genotyping must be matched by advances in phenotyping. A better understanding of genetic variation in rice for drought response, root traits, and practical methods for studying them are needed. In this study, the OryzaSNP set (20 diverse genotypes that have been genotyped for SNP markers) was phenotyped in a range of field and container studies to study the diversity of rice root growth and response to drought. Of the root traits measured across more than 20 root experiments, root dry weight showed the most stable genotypic performance across studies. The environment (E) component had the strongest effect on yield and root traits. We identified genomic regions correlated with root dry weight, percent deep roots, maximum root depth, and grain yield based on a correlation analysis with the phenotypes and aus, indica, or japonica introgression regions using the SNP data. Two genomic regions were identified as hot spots in which root traits and grain yield were co-located; on chromosome 1 (39.7–40.7 Mb) and on chromosome 8 (20.3–21.9 Mb). Across experiments, the soil type/ growth medium showed more correlations with plant growth than the container dimensions. Although the correlations among studies and genetic co-location of root traits from a range of study systems points to their potential utility to represent responses in field studies, the best correlations were observed when the two setups had some similar properties. Due to the co-location of the identified genomic regions (from introgression block analysis) with QTL for a number of previously reported root and drought traits, these regions are good candidates for detailed characterization to contribute to understanding rice improvement for response to drought. This study also highlights the utility of characterizing a small set of 20 genotypes for root growth, drought response, and related genomic regions

    The Role of Plants in the Effects of Global Change on Nutrient Availability and Stoichiometry in the Plant-Soil System  

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    Software license management in a municipal organization

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    Forskningen visar att förĂ€ndringar av informationsteknologin och en ökande anskaffning av nya programvaror har lett till underliggande problem som kan drabba heterogena programvarulicensmiljöer och stora organisationer. Underliggande problem i den stora kontexten Ă€r mjukvaruhantering. Licenshantering av programvaror Ă€r just en förgrening av det stora problemet. Stora organisationer som en kommunal verksamhet Ă€r drabbad av det hĂ€r underliggande problemet pĂ„ grund av komplexitet hos organisationens miljö. Att tillĂ€mpa förĂ€ndringar i omrĂ„det programvarulicens Ă€r omöjligt utan att göra förĂ€ndringar i hela den organisationsprocess som följer med det. Fallstudiens uppdrag Ă€r ett nytt omfattande omrĂ„de kring licenshantering av programvaror som kan vara vĂ€ldigt lĂ€rorikt och en bra erfarenhet att ta del av. Uppsatsen beskriver hur en kommunal verksamhets licenshantering av programvaror ser ut och de problem som finns med den nuvarande licenshanteringsprocessen. Förarbetet med en litteraturstudie tillsammans med datagenereringsmetoderna intervjuer, dokumentstudier och observationer anvĂ€nds för att studera fallet pĂ„ djupet. MĂ„let Ă€r att kunna ta fram de nuvarande problem som finns, analysera dem och ge rekommendation för Ă„tgĂ€rder som det studerade fallobjektet, Falu Kommuns IT-kontor, kan anvĂ€nda. En rekommendation för en tydlig licenshanteringsprocessmodell anses vara ett bra akademiskt bidrag eftersom problemet med licenshanteringen av programvaror Ă€r ett generellt problem. Uppsatsens resultat Ă€r en processmodell om licenshantering av programvaror för organisationer med IT-tjĂ€nstkunder. Det Ă€r en generisk lösning som skulle kunna anvĂ€ndas av andra kommunverksamheter och liknande organisationer.Research shows that changes in information technology and the increasing cost of new software have led to the underlying problems that affect heterogeneous software license environments and large organizations. This underlying problem in its large context is about software management. Software license management is just a small branch of this underlying problem. Large organizations like municipalities are affected by this underlying problem because of the complexity of the organization's environment. Applying changes in the area of software licensing is impossible to do without making changes to the entire organizational process that comes with it.This case study is a new extensive area surrounding the subject on license management of software, which can be very informative and good experience to share. The thesis describes how a municipal’s license management activity looks and the problems that exist with the current software license management process.Research preparations, review of literature and data generating methods; interviews, documents and observations are used to study the case object in-depth. The goal is to list the existing problems, analyze them and give recommendations for applicable solutions the case study object, IT-office in the municipality of Falun, can use.A recommendation for a clear license management process model is considered as a good academic contribution because the problem of software license management is a general problem. The thesis result is a process model about software license management for organizations with IT-service customers. This generic solution could be used by other municipalities and similar organizations

    Software license management in a municipal organization

    No full text
    Forskningen visar att förĂ€ndringar av informationsteknologin och en ökande anskaffning av nya programvaror har lett till underliggande problem som kan drabba heterogena programvarulicensmiljöer och stora organisationer. Underliggande problem i den stora kontexten Ă€r mjukvaruhantering. Licenshantering av programvaror Ă€r just en förgrening av det stora problemet. Stora organisationer som en kommunal verksamhet Ă€r drabbad av det hĂ€r underliggande problemet pĂ„ grund av komplexitet hos organisationens miljö. Att tillĂ€mpa förĂ€ndringar i omrĂ„det programvarulicens Ă€r omöjligt utan att göra förĂ€ndringar i hela den organisationsprocess som följer med det. Fallstudiens uppdrag Ă€r ett nytt omfattande omrĂ„de kring licenshantering av programvaror som kan vara vĂ€ldigt lĂ€rorikt och en bra erfarenhet att ta del av. Uppsatsen beskriver hur en kommunal verksamhets licenshantering av programvaror ser ut och de problem som finns med den nuvarande licenshanteringsprocessen. Förarbetet med en litteraturstudie tillsammans med datagenereringsmetoderna intervjuer, dokumentstudier och observationer anvĂ€nds för att studera fallet pĂ„ djupet. MĂ„let Ă€r att kunna ta fram de nuvarande problem som finns, analysera dem och ge rekommendation för Ă„tgĂ€rder som det studerade fallobjektet, Falu Kommuns IT-kontor, kan anvĂ€nda. En rekommendation för en tydlig licenshanteringsprocessmodell anses vara ett bra akademiskt bidrag eftersom problemet med licenshanteringen av programvaror Ă€r ett generellt problem. Uppsatsens resultat Ă€r en processmodell om licenshantering av programvaror för organisationer med IT-tjĂ€nstkunder. Det Ă€r en generisk lösning som skulle kunna anvĂ€ndas av andra kommunverksamheter och liknande organisationer.Research shows that changes in information technology and the increasing cost of new software have led to the underlying problems that affect heterogeneous software license environments and large organizations. This underlying problem in its large context is about software management. Software license management is just a small branch of this underlying problem. Large organizations like municipalities are affected by this underlying problem because of the complexity of the organization's environment. Applying changes in the area of software licensing is impossible to do without making changes to the entire organizational process that comes with it.This case study is a new extensive area surrounding the subject on license management of software, which can be very informative and good experience to share. The thesis describes how a municipal’s license management activity looks and the problems that exist with the current software license management process.Research preparations, review of literature and data generating methods; interviews, documents and observations are used to study the case object in-depth. The goal is to list the existing problems, analyze them and give recommendations for applicable solutions the case study object, IT-office in the municipality of Falun, can use.A recommendation for a clear license management process model is considered as a good academic contribution because the problem of software license management is a general problem. The thesis result is a process model about software license management for organizations with IT-service customers. This generic solution could be used by other municipalities and similar organizations

    Utilizing Chromosome Segment Substitution Lines (CSSLs) for Evaluation of Root Responses to Transient Moisture Stresses in Rice

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    Drought and waterlogging that occur sequentially under field conditions are important abiotic stresses affecting plant growth and development. The ability to maintain the root system development during the contrasting moisture stresses may be one of the key traits for plant adaptation. This study aimed to identify the key root traits that contributed to the above ability by comparatively examining the effects of the two moisture stresses in succession on root system development. The chromosome segment substitution lines (CSSLs) from the crosses between the japonica rice cultivar Nipponbare and indica rice cultivar Kasalath were used for precise comparison of root system development. The rice seedlings were grown by hydroponics under a continuously well-aerated condition for 14 days (non-stressed), a drought condition for 7 days followed by an oxygen (O2)-deficient (stagnant) condition for 7 days (drought-to-stagnant, D-S), or a stagnant condition for 7 days followed by drought condition for 7 days (stagnant-to-drought, S-D). CSSL43 and 47 did not show any significant differences in growth from Nipponbare under the non-stressed condition, but exhibited greater lateral root production under the stresses. Lateral root production was most closely related to faster seminal root elongation mediated by higher aerenchyma formation in the D-S condition, and to more branching of lateral roots on the seminal root axis in the S-D condition. The D-S condition severely affected lateral root production due to reduced seminal root elongation and aerenchyma formation. These results confirmed the fact that those root traits previously identified using different cultivars greatly contribute to plant adaptation. Oxygen deficiency preceded by drought (D-S) was more stressful to roots than drought preceded by O2 deficiency (S-D), because drought reduced root aerenchyma formation during the subsequent stagnant condition

    Genotypic Variations in Responses of Lateral Root Development to Transient Moisture Stresses in Rice Cultivars

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    Soil water regimes under field conditions inevitably tend to fluctuate ranging from drought to waterlogging. Genotypes that adapt better to such changing hydrologic conditions are assumed to have the ability to maintain root system development under such conditions. This study aimed to evaluate the responses of root system development based on lateral root production to transient moisture stresses, and the contribution of the elongation of seminal and nodal root axes and their lateral, root branching, and aerenchyma development in the seminal root axis, to root system development. The seedlings of two aerobic genotypes (UPLRi7 and NSICRc9) and one irrigated-lowland genotype (PSBRc82), and two parental genotypes (Nipponbare and Kasalath) of chromosome segment substitution lines (CSSLs) were grown by hydroponics. The seedlings were exposed to a drought condition by adding polyethylene glycol to the solution for 7 days and then to an O2-deficient stagnant condition for 7 days (drought-to-stagnant condition), or to reverse successive conditions (stagnant-to-drought condition). Under both conditions, the aerobic genotypes showed greater ability to produce lateral roots than the irrigated-lowland genotype. Under the transient stagnant-to-drought condition, the root traits that contributed to greater lateral root production in the aerobic genotypes were faster seminal root elongation that was closely associated with branching of lateral roots, and greater nodal root production. Under transient drought to stagnant condition; these were faster seminal root elongation mediated by higher aerenchyma formation, and greater nodal root production. Kasalath showed much greater ability to produce lateral roots under both transient moisture stress conditions than Nipponbare. This indicates the potential utility of the CSSLs for precise identification of desirable root traits with less genetic confounding

    Developmental Plasticity of Rice Root System Grown under Mild Drought Stress Condition with Shallow Soil Depth; Comparison between Nodal and Lateral roots

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    The plasticity in root system development (RSD) is a key trait for the adaptation of rice to mild drought. However, the enhanced RSD due to the plasticity may not be always a sole function of promoted lateral root (LR) production, but also of the integrated responses of nodal root (NR) development. In this study, we aimed to evaluate the effects of mild drought intensities on the development of the NR and LR, and their contribution to the entire RSD. We used six genotypes including KDML105 (indica, lowland adapted), a high lateral rooting ability genotype. The plants were grown up to heading or maturity stage for two years under soil with limited soil depth (20 cm) assuming the presence of the hardpan and at different moisture gradients generated by the line source sprinkler system. The effects of drought intensities generally differed between the development of NR and LR. In both years, all genotypes showed highest LR development under mild drought stress intensities. However, in some genotypes including KDML105, NR development was maintained in a limited soil moisture range only, which was narrower and wetter than that in which LR plasticity was expressed. Furthermore, the entire RSD was maintained only when both the NR and LR were simultaneously promoted or maintained. These results suggest that the NR have less plasticity than the LR in response to drought and the contribution of the plasticity in LR development to the entire RSD is dependent on both the soil moisture and nodal rooting ability
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