Browsing by Subject "plant morphology"

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    Genetic structure and phenotypic differences among and within extant populations of Chrysanthemum arcticum L. and C. a. subsp. arcticum
    (2020-07) Liu, Yunjia
    Chrysanthemum arcticum L., Arctic daisy, (=Arctanthemum arcticum; =Dendranthema arcticum) and its two subspecies (C. arcticum L. subsp. arcticum, C. arcticum L. subsp. polaré Hulten), collectively the C. arcticum species complex, are the only chrysanthemum species native to North America. The species are of interest since they are salt tolerant, growing only along the oceans, with a groundcover habit and may possess other ornamental traits of value to chrysanthemum breeders. However, evidence of decline in species’ range of distribution were detected, which may be reducing the genetic diversity. Understanding the genetic diversity and population structure is important in order to develop conservation strategies and utilize valuable germplasm resources. Thus, we have collected and genotyped 529 genotypes in nine C. arcticum and 21 C. a. ssp. arcticum extant populations from the State of Alaska mainland and Attu Island (the westernmost Aleutian Island). Population genetic diversity was analyzed using 7,449 SNP markers from DArTseqLD. Simultaneously, 16 quantitative morphological traits and 5 qualitative morphological traits were investigated for phenotypic differences. Three distinct genetic clusters were detected by STRUCTURE 2.3.4 within C. arcticum populations and consistent results were obtained with Principal coordinate analysis (PCoA), Discriminant analysis of principal components (DAPC), and the Unweighted pair group method with arithmetic means (UPGMA), while a mixture of subgroups were present in C. a. subsp. arcticum populations genetic cluster analyses, which may be the result of gene flow among close populations capable of gene exchange (Chapter 2). The study on the species’ variation in morphological and diagnostic traits is of importance to enhance diagnostic traits for species identification and link morphological traits with single nucleotide polymorphism (SNP) markers. Soil samples revealed extremely high levels of Na, which confirmed that the species are salt-tolerant. Univariate ANOVAs revealed significant differences among species and morphological traits, similar to the genetic structure analysis for variation among populations within members of the C. arcticum species complex. Overlaps in the genetic cluster analysis for C. a. subsp. arcticum verified the possibility of a higher frequency of gene flow among Attu island collection sites (chapter 3).
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    New handbook for standardised measurement of plant functional traits worldwide
    (CSIRO, 2013) Pérez-Harguindeguy, N; Díaz, S; Garnier, E; Lavorel, S; Poorter, H; Jaureguiberry, P; Bret-Harte, M S; Cornwell, W K; Craine, J M; Gurvich, D E; Urcelay, C; Veneklaas, E J; Reich, Peter B; Poorter, L; Wright, I J; Ray, P; Enrico, L; Pausas, J G; de Vos, A C; Buchmann, N; Funes, G; Quétier, F; Hodgson, J G; Thompson, K; Morgan, H D; ter Steege, H; van der Heijden, M G A; Sack, L; Blonder, B; Poschlod, P; Vaieretti, M V; Conti, G; Staver, A C; Aquino, S; Cornelissen, J H C
    Plant functional traits are the features (morphological, physiological, phenological) that represent ecological strategies and determine how plants respond to environmental factors, affect other trophic levels and influence ecosystem properties. Variation in plant functional traits, and trait syndromes, has proven useful for tackling many important ecological questions at a range of scales, giving rise to a demand for standardised ways to measure ecologically meaningful plant traits. This line of research has been among the most fruitful avenues for understanding ecological and evolutionary patterns and processes. It also has the potential both to build a predictive set of local, regional and global relationships between plants and environment and to quantify a wide range of natural and human-driven processes, including changes in biodiversity, the impacts of species invasions, alterations in biogeochemical processes and vegetation–atmosphere interactions. The importance of these topics dictates the urgent need for more and better data, and increases the value of standardised protocols for quantifying trait variation of different species, in particular for traits with power to predict plant- and ecosystemlevel processes, and for traits that can be measured relatively easily. Updated and expanded from the widely used previous version, this handbook retains the focus on clearly presented, widely applicable, step-by-step recipes, with a minimum of text on theory, and not only includes updated methods for the traits previously covered, but also introduces many new protocols for further traits. This new handbook has a better balance between whole-plant traits, leaf traits, root and stem traits and regenerative traits, and puts particular emphasis on traits important for predicting species’ effects on key ecosystem properties.We hope this new handbook becomes a standard companion in local and global efforts to learn about the responses and impacts of different plant species with respect to environmental changes in the present, past and future.