1,326 research outputs found

    Accumulation of 5-hydroxynorvaline in maize (Zea mays) leaves is induced by insect feeding and abiotic stress.

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    Plants produce a wide variety of defensive metabolites to protect themselves against herbivores and pathogens. Non-protein amino acids, which are present in many plant species, can have a defensive function through their mis-incorporation during protein synthesis and/or inhibition of biosynthetic pathways in primary metabolism. 5-Hydroxynorvaline was identified in a targeted search for previously unknown non-protein amino acids in the leaves of maize (Zea mays) inbred line B73. Accumulation of this compound increases during herbivory by aphids (Rhopalosiphum maidis, corn leaf aphid) and caterpillars (Spodoptera exigua, beet armyworm), as well as in response to treatment with the plant signalling molecules methyl jasmonate, salicylic acid and abscisic acid. In contrast, ethylene signalling reduced 5-hydroxynorvaline abundance. Drought stress induced 5-hydroxynorvaline accumulation to a higher level than insect feeding or treatment with defence signalling molecules. In field-grown plants, the 5-hydroxynorvaline concentration was highest in above-ground vegetative tissue, but it was also detectable in roots and dry seeds. When 5-hydroxynorvaline was added to aphid artificial diet at concentrations similar to those found in maize leaves and stems, R. maidis reproduction was reduced, indicating that this maize metabolite may have a defensive function. Among 27 tested maize inbred lines there was a greater than 10-fold range in the accumulation of foliar 5-hydroxynorvaline. Genetic mapping populations derived from a subset of these inbred lines were used to map quantitative trait loci for 5-hydroxynorvaline accumulation to maize chromosomes 5 and 7

    Alternatives for Scheduling the Bar

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    Controlling Cattail Invasion in Sedge / Grass Meadows

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    As a result of water-level regulation, cattails have invaded sedge/grass meadow in all wetlands on Lake Ontario. Even with a change in water-level-regulation to a more natural hydrologic regime, restoration requires methods for active cattail management without the ability to manipulate water depths and without imperiling other vegetation. We conducted replicated studies at a wetland site with an active invasion front in zones of nearly mono-dominant cattail and transitional invasion. We tested various combinations of cutting cattail ramets when carbohydrate reserves were minimized, spraying cut stems with herbicide, slicing rhizomes to mimic tilling, and hand-wicking resprouted ramets with herbicide.We also collected companion environmental data. The most effective treatment in both zones was cutting during the period with reduced rhizome carbohydrates followed by handwicking resprouted ramets with herbicide in late summer, which allows the herbicide to be absorbed by the rhizomes. Two years of treatment provide the best results, reducing cattail stem counts and cover by more than 50%, but follow-up applications in ensuing years may be warranted to treat surviving cattails. Given the widespread problem of cattail invasion, these treatments may have broad application in wetlands where water levels cannot be manipulated

    Novel Bayesian Networks for Genomic Prediction of Developmental Traits in Biomass Sorghum.

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    The ability to connect genetic information between traits over time allow Bayesian networks to offer a powerful probabilistic framework to construct genomic prediction models. In this study, we phenotyped a diversity panel of 869 biomass sorghum (Sorghum bicolor (L.) Moench) lines, which had been genotyped with 100,435 SNP markers, for plant height (PH) with biweekly measurements from 30 to 120 days after planting (DAP) and for end-of-season dry biomass yield (DBY) in four environments. We evaluated five genomic prediction models: Bayesian network (BN), Pleiotropic Bayesian network (PBN), Dynamic Bayesian network (DBN), multi-trait GBLUP (MTr-GBLUP), and multi-time GBLUP (MTi-GBLUP) models. In fivefold cross-validation, prediction accuracies ranged from 0.46 (PBN) to 0.49 (MTr-GBLUP) for DBY and from 0.47 (DBN, DAP120) to 0.75 (MTi-GBLUP, DAP60) for PH. Forward-chaining cross-validation further improved prediction accuracies of the DBN, MTi-GBLUP and MTr-GBLUP models for PH (training slice: 30-45 DAP) by 36.4-52.4% relative to the BN and PBN models. Coincidence indices (target: biomass, secondary: PH) and a coincidence index based on lines (PH time series) showed that the ranking of lines by PH changed minimally after 45 DAP. These results suggest a two-level indirect selection method for PH at harvest (first-level target trait) and DBY (second-level target trait) could be conducted earlier in the season based on ranking of lines by PH at 45 DAP (secondary trait). With the advance of high-throughput phenotyping technologies, our proposed two-level indirect selection framework could be valuable for enhancing genetic gain per unit of time when selecting on developmental traits

    Experiential learning about medication adherence

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140039/1/tct12645.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/140039/2/tct12645_am.pd

    The Transpersonal That Can Be Defined Is Not the True Transpersonal: a Taoist Perspective on Defining Transpersonal Psychology (Position Paper)

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    This brief position paper is stimulated from the continued need to define and redefine the area of transpersonal psychology. Understandably, being able to articulate what ‘transpersonal psychology’ is enables discussions within the wider academic and public community, yet all existing definitions are complex, conveying a number of inherent meanings in their definition, which in turn, can cloud others’ perceptions on the area
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