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Parallel Expression Evolution Of Oxidative Stress-Related Genes In Fiber From Wild And Domesticated Diploid And Polyploid Cotton (Gossypium), Bhupendra Chaudhary, Ran Hovav, Lex Flagel, Ron Mittler, Jonathan F. Wendel Aug 2009

Parallel Expression Evolution Of Oxidative Stress-Related Genes In Fiber From Wild And Domesticated Diploid And Polyploid Cotton (Gossypium), Bhupendra Chaudhary, Ran Hovav, Lex Flagel, Ron Mittler, Jonathan F. Wendel

Ecology, Evolution and Organismal Biology Publications

Reactive oxygen species (ROS) play a prominent role in signal transduction and cellular homeostasis in plants. However, imbalances between generation and elimination of ROS can give rise to oxidative stress in growing cells. Because ROS are important to cell growth, ROS modulation could be responsive to natural or human-mediated selection pressure in plants. To study the evolution of oxidative stress related genes in a single plant cell, we conducted comparative expression profiling analyses of the elongated seed trichomes ("fibers") of cotton (Gossypium), using a phylogenetic approach. We measured expression changes during diploid progenitor species divergence, allopolyploid formation and parallel domestication ...


Initiation And Early Development Of Fiber In Wild And Cultivated Cotton, Kara M. Butterworth, Dean C. Adams, Harry T. Horner, Jonathan F. Wendel Jun 2009

Initiation And Early Development Of Fiber In Wild And Cultivated Cotton, Kara M. Butterworth, Dean C. Adams, Harry T. Horner, Jonathan F. Wendel

Ecology, Evolution and Organismal Biology Publications

Cultivated cotton fiber has undergone transformation from short, coarse fibers found in progenitor wild species to economically important, long, fine fibers grown globally. Morphological transformation requires understanding of development of wild fiber and developmental differences between wild and cultivated fiber.We examined early development of fibers, including abundance and placement on seed surface, nucleus position, presence of vacuoles, and fiber size and shape. Four species were studied using microscopic, morphometric, and statistical methods: Gossypium raimondii (wild D genome), Gossypium herbaceum (cultivated A genome), Gossypium hirsutum (wild tetraploid), and Gossypium hirsutum (cultivated tetraploid). Early fiber development is highly asynchronous in G ...


Biodiversity, Productivity And The Temporal Stability Of Productivity: Patterns And Processes, Forest I. Isbell, H. Wayne Polley, Brian J. Wilsey May 2009

Biodiversity, Productivity And The Temporal Stability Of Productivity: Patterns And Processes, Forest I. Isbell, H. Wayne Polley, Brian J. Wilsey

Ecology, Evolution and Organismal Biology Publications

Theory predicts that the temporal stability of productivity, measured as the ratio of the mean to the standard deviation of community biomass, increases with species richness and evenness. We used experimental species mixtures of grassland plants to test this hypothesis and identified the mechanisms involved. Additionally, we tested whether biodiversity, productivity and temporal stability were similarly influenced by particular types of species interactions. We found that productivity was less variable among years in plots planted with more species. Temporal stability did not depend on whether the species were planted equally abundant (high evenness) or not (realistically low evenness). Greater richness ...


Genomic Expression Dominance In Allopolyploids, Ryan A. Rapp, Joshua A. Udall, Jonathan F. Wendel May 2009

Genomic Expression Dominance In Allopolyploids, Ryan A. Rapp, Joshua A. Udall, Jonathan F. Wendel

Ecology, Evolution and Organismal Biology Publications

Allopolyploid speciation requires rapid evolutionary reconciliation of two diverged genomes and gene regulatory networks. Here we describe global patterns of gene expression accompanying genomic merger and doubling in inter-specific crosses in the cotton genus (Gossypium L.). Employing a micro-array platform designed against 40,430 unigenes, we assayed gene expression in two sets of parental diploids and their colchicine-doubled allopolyploid derivatives. Up to half of all genes were differentially expressed among diploids, a striking level of expression evolution among congeners. In the allopolyploids, most genes were expressed at mid-parent levels, but this was achieved via a phenomenon of genome-wide expression dominance ...


Heterogeneity Of Phosphorus Distribution In A Patterned Landscape, The Florida Everglades, Paul R. Wetzel, Arnold G. Van Der Valk, Susan Newman, Carlos A. Coronado, Tiffany G. Troxler-Gann, Daniel L. Childers, William H. Orem, Fred H. Sklar Jan 2009

Heterogeneity Of Phosphorus Distribution In A Patterned Landscape, The Florida Everglades, Paul R. Wetzel, Arnold G. Van Der Valk, Susan Newman, Carlos A. Coronado, Tiffany G. Troxler-Gann, Daniel L. Childers, William H. Orem, Fred H. Sklar

Ecology, Evolution and Organismal Biology Publications

The biologically mediated transfer of nutrients from one part of a landscape to another may create nutrient gradients or subsidize the productivity at specific locations. If limited, this focused redistribution of the nutrient may create non-random landscape patterns that are unrelated to underlying environmental gradients. The Florida Everglades, USA, is a large freshwater wetland that is patterned with tree islands, elevated areas that support woody vegetation. A survey of 12 tree islands found total soil phosphorus levels 3–114 times greater on the island head than the surrounding marsh, indicating that the Florida Everglades is not a homogeneous oligotrophic system ...