Undergraduates Phenotyping Knockouts in a Course-Based Undergraduate Research Experience: Exploring Plant Fitness and Vigor Using Quantitative Phenotyping Methods.

We present a curriculum description, an initial student outcome investigation, and sample scientific results for a representative Course-Based Undergraduate Research Experience (CURE) that is part of the "Undergraduates Phenotyping Knockouts" (unPAK) network. CUREs in the unPAK network characterize quantitative phenotypes of the model plant from across environments to uncover connections between genotype and phenotype. Students in unPAK CUREs grow plants in a replicated block design and make quantitative measurements throughout the semester.

Distributed phenomics with the unPAK project reveals the effects of mutations.

Determining how genes are associated with traits in plants and other organisms is a major challenge in modern biology. The unPAK project - undergraduates phenotyping Arabidopsis knockouts - has generated phenotype data for thousands of non-lethal insertion mutation lines within a single Arabidopsis thaliana genomic background. The focal phenotypes examined by unPAK are complex macroscopic fitness-related traits, which have ecological, evolutionary and agricultural importance.

Evolution of leaf structure and drought tolerance in species of Californian Ceanothus.

Premise Of The Study: Studies across diverse species have established theory for the contribution of leaf traits to plant drought tolerance. For example, species in more arid climates tend to have smaller leaves of higher vein density, higher leaf mass per area, and more negative osmotic potential at turgor loss point (π ). However, few studies have tested these associations for species within a given lineage that have diversified across an aridity gradient.

Patterns in root traits of woody species hosting arbuscular and ectomycorrhizas: implications for the evolution of belowground strategies.

Root traits vary enormously among plant species but we have little understanding of how this variation affects their functioning. Of central interest is how root traits are related to plant resource acquisition strategies from soil. We examined root traits of 33 woody species from northeastern US forests that form two of the most common types of mutualisms with fungi, arbuscular mycorrhizas (AM) and ectomycorrhizas (EM).

Evolutionary change in continuous reaction norms.

Understanding the evolution of reaction norms remains a major challenge in ecology and evolution. Investigating evolutionary divergence in reaction norm shapes between populations and closely related species is one approach to providing insights. Here we use a meta-analytic approach to compare divergence in reaction norms of closely related species or populations of animals and plants across types of traits and environments.

Experimentally reduced root-microbe interactions reveal limited plasticity in functional root traits in Acer and Quercus.

Background And Aims: Interactions between roots and soil microbes are critical components of below-ground ecology. It is essential to quantify the magnitude of root trait variation both among and within species, including variation due to plasticity. In addition to contextualizing the magnitude of plasticity relative to differences between species, studies of plasticity can ascertain if plasticity is predictable and whether an environmental factor elicits changes in traits that are functionally advantageous.

Phenotypic plasticity, costs of phenotypes, and costs of plasticity: toward an integrative view.

Why are some traits constitutive and others inducible? The term costs often appears in work addressing this issue but may be ambiguously defined. This review distinguishes two conceptually distinct types of costs: phenotypic costs and plasticity costs. Phenotypic costs are assessed from patterns of covariation, typically between a focal trait and a separate trait relevant to fitness.

Using artificial selection to understand plastic plant phenotypes.

The plasticity of any given trait, which has a genetic basis and which may or may not be adaptive, can intensify or attenuate evolved responses, and can itself evolve in response to selection depending on the scale of spatial or temporal heterogeneity. To investigate the complex function and evolution of plastic traits, an appealing yet challenging approach is assessing responses to artificial selection. Here, I review how artificial selection has been employed to explore four botanical research themes: (1) relationships between plastic and evolved responses to multiple stresses, (2) integration of cellular, leaf-level, and whole-plant responses to altered CO(2) concentrations, (3) photomorphogenic and photoperiodic development, both mediated by phytochrome photoreceptors, and (4) the evolution of the pest-induced myrosinase-glucosinolate system in cruciferous plants.

Plasticity genes and plasticity costs: a new approach using an Arabidopsis recombinant inbred population.

Earlier flowering is triggered by vernalization in some but not all Arabidopsis ecotypes, often reflecting allelic variation at the FRIGIDA (FRI) locus. Using a recombinant inbred (RI) population polymorphic at FRI, we examined fitness consequences of variation for plasticity. Flowering and fitness were scored for 68 RI genotypes following full and partial vernalization treatments.

MEASURING NATURAL SELECTION ON PHENOTYPIC PLASTICITY.

To understand natural selection we need to integrate its measure across environments. We present a method for measuring phenotypic selection that combines the potential for both environmental variation and phenotypic plasticity. The method uses path analysis and a measure of selection that is analogous to selection on breeding values.