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Item Understanding the biology, ecology, and integrated managment of Ventenata dubia(Montana State University - Bozeman, College of Agriculture, 2019) Harvey, Audrey June; Chairperson, Graduate Committee: Jane M. Mangold; Lisa Rew, Timothy Prather and Jane Mangold were co-authors of the article, 'The effects of elevated temperature and CO 2 concentration on seedling growth of Ventenata dubia and Bromus tectorum' submitted to the journal 'Western North American naturalist' which is contained within this thesis.; Lisa Rew, Timothy Prather and Jane Mangold were co-authors of the article, 'Indaziflam provided up to three-years of control for Ventenata dubia in southwestern Montana' submitted to the journal 'Invasive plant science and management' which is contained within this thesis.; Stacy Davis, Lisa Rew, Timothy Prather and Jane Mangold were co-authors of the article, 'Effect of seeding date of Pseudoroegneria spicata (bluebunch wheatgrass) on establishment and subsequent ability to resist invasion by Bromus tectorum (cheatgrass)' submitted to the journal 'Ecological restoration' which is contained within this thesis.Ventenata dubia (Leers) Coss., common name ventenata or African wire grass, is a non-native winter annual grass of increasing concern in western Montana. In North American, V. dubia appeared in the early 1950s; since then it has successfully established in the northeastern and northwestern United States. It is known to invade areas previously inhabited by Bromus tectorum (cheatgrass) and Taeniatherum caput-medusae (medusahead). In the Intermountain Pacific Northwest, V. dubia has caused substantial ecological and economic impacts in perennial grass habitats. Varying disturbance regimes contribute to its rapid expansion over the last decade. Impending climate change threats have the potential to exacerbate the spread of this invasive species. Three independent studies were conducted to explore the biology, ecology, and integrated management of V. dubia populations in Montana to alleviate impacts by this species and other invasive annual grasses. A growth chamber study tested the effects of elevated carbon dioxide and temperature on seedling growth of V. dubia in response to climate change and in competition with B. tectorum. This competition replacement study indicated that at elevated climate conditions V. dubia and B. tectorum grow smaller and competition with V.dubia has the potential to decrease B. tectorum growth. A field-based herbicide efficacy trial utilizing the active ingredient indaziflam compared it to other commonly used herbicides to determine long-term control of V. dubia and potential plant community changes at 8, 11, 20, and 23 months after treatment. Foliar cover, species richness, and functional group biomass were collected. Findings indicated indaziflam can control V. dubia up to three years with positive implications for plant community dynamics. A revegetation study was used to determine the optimum seeding time for perennial grass species, Pseudoroegneria spicata, and the effects seeding time can have with competition dynamics with B. tectorum. A randomized complete block design was established and P. spicata grown for one season prior to Bromus tectorum seeding. After the second growing season, tillers and biomass were collected for both species. Findings indicated priority effects can occur with fall and early spring seeding of P. spicata, with implications for suppression of B. tectorum at earlier seeding dates.Item Growth of Chlamydomonas reinhardtii in acetate-free medium when co-cultured with alginate-encapsulated, acetate-producing strains ofSynechococcus sp. PCC 7002(2014-10) Therien, Jesse B.; Zadvornyy, Oleg A.; Posewitz, Matthew C.; Bryant, Donald A.; Peters, John W.Background: The model alga Chlamydomonas reinhardtii requires acetate as a co-substrate for optimal production of lipids, and the addition of acetate to culture media has practical and economic implications for algal biofuel production. Here we demonstrate the growth of C. reinhardtii on acetate provided by mutant strains of the cyanobacterium Synechococcus sp. PCC 7002. Results: Optimal growth conditions for co-cultivation of C. reinhardtii with wild-type and mutant strains of Synechococcus sp. 7002 were established. In co-culture, acetate produced by a glycogen synthase knockout mutant of Synechococcus sp. PCC 7002 was able to support the growth of a lipid-accumulating mutant strain of C. reinhardtii defective in starch production. Encapsulation of Synechococcus sp. PCC 7002 using an alginate matrix was successfully employed in co-cultures to limit growth and maintain the stability. Conclusions: The ability of immobilized strains of the cyanobacterium Synechococcus sp. PCC 7002 to produce acetate at a level adequate to support the growth of lipid-accumulating strains of C. reinhartdii offers a potentially practical, photosynthetic alternative to providing exogenous acetate into growth media.Item Draft Genome Sequence of the Moderately Thermophilic Bacterium Schleiferia thermophila Strain Yellowstone (Bacteroidetes)(2014-07) Thiel, Vera; Tomsho, Lynn P.; Burhans, Richard; Gay, Scott E.; Ramaley, R. F.; Schuster, Stephan C.; Steinke, L.; Bryant, Donald A.The draft genome sequence of the moderately thermophilic bacterium Schleiferia thermophila strain Yellowstone (Bacteroidetes), isolated from Octopus Spring (Yellowstone National Park, WY, USA) was sequenced and comprises 2,617,694 bp in 35 contigs. The draft genome is predicted to encode 2,457 protein coding genes and 37 tRNA encoding genes and two rRNA operons.Item Draft Genome Sequence of a Sulfide-Oxidizing, Autotrophic Filamentous Anoxygenic Phototrophic Bacterium, Chloroflexus sp. Strain MS-G (Chloroflexi)(2014-09) Thiel, Vera; Tomsho, Lynn P.; Burhans, Richard; Schuster, Stephan C.; Bryant, Donald A.; Ward, David M.The draft genome sequence of the thermophilic filamentous anoxygenic phototrophic bacterium Chloroflexus sp. strain MS-G (Chloroflexi), isolated from Mushroom Spring (Yellowstone National Park, WY, USA) was sequenced and comprises 4,784,183 bp in 251 contigs. The draft genome is predicted to encode 4,059 protein coding genes, 49 tRNA encoding genes, and 3 rRNA operons.Item Occurrence of Far-Red Light Photoacclimation (FaRLiP) in Diverse Cyanobacteria(2014-12) Gan, Fei; Shen, Gaozhong; Bryant, Donald A.Cyanobacteria have evolved a number of acclimation strategies to sense and respond to changing nutrient and light conditions. Leptolyngbya sp. JSC-1 was recently shown to photoacclimate to far-red light by extensively remodeling its photosystem (PS) I, PS II and phycobilisome complexes, thereby gaining the ability to grow in far-red light. A 21-gene photosynthetic gene cluster (rfpA/B/C, apcA2/B2/D2/E2/D3, psbA3/D3/C2/B2/ H2/A4, psaA2/B2/L2/I2/F2/J2) that is specifically expressed in far-red light encodes the core subunits of the three major photosynthetic complexes. The growth responses to far-red light were studied here for five additional cyanobacterial strains, each of which has a gene cluster similar to that in Leptolyngbya sp. JSC-1. After acclimation all five strains could grow continuously in far-red light. Under these growth conditions each strain synthesizes chlorophylls d, f and a after photoacclimation, and each strain produces modified forms of PS I, PS II (and phycobiliproteins) that absorb light between 700 and 800 nm. We conclude that these photosynthetic gene clusters are diagnostic of the capacity to photoacclimate to and grow in far-red light. Given the diversity of terrestrial environments from which these cyanobacteria were isolated, it is likely that FaRLiP plays an important role in optimizing photosynthesis in terrestrial environments.