5 research outputs found
Testing for Genomic Control of Ephemeral Leaf Phenotypes in \u3cem\u3eArtemisia tridentata\u3c/em\u3e
Climate change is driving ever increasing ecological stresses on native plant communities. Furthering our understanding of how plants, particularly keystone species of important ecosystems, deal with these stresses will be essential for the success of conservation and restoration efforts Artemisia tridentate is a keystone species of western North America and has experience sharp population declines in recent decades due to human activity. During the late winter and early spring months, A. tridentate grows large ephemeral leaves that provide more surface area for light capture and photosynthesis while resources are abundant. Then, during the onset of drought stress during the summer months, the ephemeral leaves will drop. We hypothesize that the timing of ephemeral leaf dropping is correlated to important water use efficiency traits and are under genomic control. To test these hypotheses, plants of a population of A. tridentate near Marsing, ID were tracked and phenotyped from late spring though summer. Early and late ephemeral leaf dropping individuals then had their genomes sequenced for genetic association tests. We find that there are statistically significant differences for leaf phenotypes among individuals, suggesting that the water use efficiency will vary within the population. Genetic tests are on-going to determine if these traits are genetically determined
Determining the Robotic Accuracy of Pedicle Screws Implanted During Spinal Fusions
Pedicle screw fixation is a lumbar spinal fusion (LSF) technique that involves the implantation of screws to act as anchor points to restrict movement between vertebrae. To improve the accuracy of these procedures, surgical robots were created to assist in spinal fusion surgery, which have reduced radiation exposure and recovery time. Our objective was to determine if robotic surgical assistance in pedicle screw implantation is within a 2mm deviation. This was assessed by overlaying the pre-op and post-op images in the Maxor X software system and measuring the deviation and angle from the planned implantation site. Preliminary results indicate that Maxor X Stealth Edition robotic guidance system is performing within the 2mm deviation in the pedicle region. These results suggest that surgical robots assisting in LSF procedures aid in accuracy of screw implantation, while lowering risk of exposure to radiation and patient recovery time
Variation in Adaptive Traits and Seed Zone Evaluation of Showy Milkweed (\u3cem\u3eAsclepias speciosa\u3c/em\u3e)
Monarch butterfly (Danuas plexippus) populations are imperiled and in review for listing under the Endangered Species Act. Among many contributors to the decline is the loss of breeding, migratory, and overwintering habitat. Showy milkweed (Asclepias speciosa) and other obligate milkweeds are essential for monarch reproduction and have thus been cornerstones of monarch habitat restoration efforts in the Intermountain West. However, many potential restoration areas lack convenient seed sources to supply prospective efforts. Furthermore, because certain populations may be better adapted to specific local climates and selective pressures, the introduction of non-native, poorly adaptive genotypes may have negative consequences for restoration efforts and milkweed-dependent species. We used a genecological approach to identify adaptive traits among 35 showy milkweed populations from the Intermountain West to inform seed transfer zones for A. speciosa. We used morphological measures and plant growth data in conjunction with remotely sensed climate data to identify putative adaptive traits and determine how they relate to local climate variation. Here we present the results of our analyses and their implications for classifying showy milkweed seed transfer zones and maximizing restoration and conservation benefit for monarch butterflies
Phenological Variation Among Western Populations of Showy Milkweed (\u3cem\u3eAsclepias speciosa\u3c/em\u3e)
Western monarch butterflies (Danaus plexippus) have declined ~97% from historic abundances in the early 1980s and are being evaluated for listing under the Endangered Species Act. Habitat loss and fragmentation in wintering, migratory, and breeding areas are considered key causes. Since monarchs depend on milkweeds (Asclepias sp.) for reproduction, there is increased interest among conservationists to plant milkweeds as habitat restoration. Showy milkweed (Aslceipias speciosa) is the most common and abundant milkweed species in the Western US. Successful habitat restoration will require germplasm that is adapted for target restoration environments and seasonal phenology. Phenological traits are adaptive, easily observable, and shaped by climate; making them helpful in genecological applications for determining seed transfer zones. We evaluated phenological variation among 35 showy milkweed populations from across the Intermountain West to determine geographic patterns of adaptive traits and their relationships to local climates using a common garden approach. We used remotely sensed climate data in conjunction with growth and reproductive phenology data to identify variation in adaptive traits and correlate them to elevation and climate variation. Here we present the results of our analyses and their implications for defining seed transfer zones for showy milkweed in the context of monarch butterfly conservation
Do Showy Milkweed (\u3cem\u3eAsclepias speciosa\u3c/em\u3e) Leaf Characteristics Respond to Environmental Conditions?
Monarch butterfly populations have declined since the 1970s due to habitat loss and fragmentation caused by human activities. Monarch conservation efforts call for the obligate host plants, milkweeds, to be replenished across the Western US. By quantifying phenological and morphological variations of Showy Milkweed across the Intermountain West, our study will delineate seed transfer zones to maximize restorations success. Successful habitat restoration will require germplasm that is adapted for target restoration environments and seasonal phenology. We recorded leaf length, width, surface area, specific leaf area, and trichome densities from ten individuals among 35 populations raised in a common garden to inform photosynthetic capabilities, water use-efficiency, and defense against herbivory. By modeling relationships among leaf characteristics, climate and known herbivore responses, we can restore milkweed that is both best adapted to the environment, and best suited to host Monarch larvae. As existing monarch butterfly populations represent less than 1% of historic abundance, effective conservation is needed to restore numbers to sustainable levels. Here we present our methodological approach for assessing leaf characters, and evaluate the implications that leaf traits have for both plant fitness and host plant suitability for monarch butterflies