Life Sciences Commons^™

Intraspecific Variation In Dehydration Tolerance: Insights From The Tropical Plant Marchantia Inflexa, Rose A. Marks

Theses and Dissertations--Biology

Plants are threatened by global change, increasing variability in weather patterns, and associated abiotic stress. Consequently, there is an urgent need to enhance our ability to predict plant community dynamics, shifts in species distributions, and physiological responses to environmental challenges. By building a fundamental understanding of plant stress tolerance, it may be possibly to protect the ecological services, economic industries, and communities that depend on plants. Dehydration tolerance (DhT) is an important mechanism of water stress tolerance with promising translational applications. Here, I take advantage natural variation in DhT to gain a deeper insight into this complex trait. In addition, …

Natural Selection For Disease Resistance In Hybrid Poplars Targets Stomatal Patterning Traits And Regulatory Genes., Karl Christian Fetter

Graduate College Dissertations and Theses

The evolution of disease resistance in plants occurs within a framework of interacting

phenotypes, balancing natural selection for life-history traits along a continuum of

fast-growing and poorly defended, or slow-growing and well-defended lifestyles. Plant

populations connected by gene flow are physiologically limited to evolving along a

single axis of the spectrum of the growth-defense trade-off, and strong local selection

can purge phenotypic variance from a population or species, making it difficult to

detect variation linked to the trade-off. Hybridization between two species that have

evolved different growth-defense trade-off optima can reveal trade-offs hidden in either

species by introducing phenotypic and …