Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 6 of 6

Full-Text Articles in Life Sciences

Relative Contribution Of Physical Interference And Allelopathy To Weed Suppression By Winter Annual Cover Crop Mixtures, Alyssa D. Travlos Dec 2018

Relative Contribution Of Physical Interference And Allelopathy To Weed Suppression By Winter Annual Cover Crop Mixtures, Alyssa D. Travlos

MSU Graduate Theses

Cover cropping systems are widely used in crop production systems to prevent erosion, improve soil health, and suppress weeds. Common cover cropping systems include combinations of cereal rye (Secale cereale L.), Brassica species, legumes, and other winter annual species. Three cover crop mixtures (cereal rye alone, cereal rye plus winter pea, and cereal rye plus winter pea plus radish) were applied using three methods (fresh residue, dried leached residue, and leachate) to common waterhemp (Amaranthus tuberculatus var. rudis) and large crabgrass [Digitaria sanguinalis (L.) Scop.]. The experiment was conducted once in a greenhouse and once in a …


Effects Of Fire Season And Temperature On A Spotted Knapweed (Centaurea Stoebe) Infested Grassland, Zachery T. Pitman Aug 2018

Effects Of Fire Season And Temperature On A Spotted Knapweed (Centaurea Stoebe) Infested Grassland, Zachery T. Pitman

Masters Theses

Invasive species, including the non-native forb Centaurea stoebe (spotted knapweed), constitute an imminent threat to degraded and restored native prairies. Considering the major threat that C. stoebe poses to imperiled prairie ecosystems, I examined the effectiveness of fire as a control agent of C. stoebe and (±)-catechin. I conducted a 2-year experiment in part of a restored tallgrass prairie community at Pierce Cedar Creek Institute in Barry County, Michigan between May and August of 2016 and 2017. My experiment consisted of individually burning 60 1-m² plots with a propane torch to achieve high (316° C) and low (103° C) temperatures …


Combinations Of Allelopathic Crop Extracts Reduce Digitaria Spp. And Setaria Faberi Seed Germination, Peter Apicella, Karl Guillard May 2018

Combinations Of Allelopathic Crop Extracts Reduce Digitaria Spp. And Setaria Faberi Seed Germination, Peter Apicella, Karl Guillard

Honors Scholar Theses

Allelopathic cover crops contain compounds that deter other types of plant seeds from germinating or inhibiting established plants’ growth. Sunflower (Helianthus annuus, SF), buckwheat (Fagopyrum esculentum Moench, BW), sorghum-sudangrass (Sorghum × drummondii [Nees ex. Steud.] Millsp. & Chase, SSG), and winter rye (Secale cereale) are all known allelopathic cover crops. However, there is little information about the use of these allelopathic cover crops used together and their combined impact on weed seed germination. Laboratory bioassays were conducted to determine the effect of the aforementioned cover crops alone and in combinations in reducing the …


Lethal Effects Of Leaf Leachate From The Non-Native Invasive Shrub Amur Honeysuckle (Lonicera Maackii) On A Model Aquatic Organism (Hyalella Azteca), Eric B. Borth, Kevin W. Custer, Ryan W. Mcewan Apr 2018

Lethal Effects Of Leaf Leachate From The Non-Native Invasive Shrub Amur Honeysuckle (Lonicera Maackii) On A Model Aquatic Organism (Hyalella Azteca), Eric B. Borth, Kevin W. Custer, Ryan W. Mcewan

Ryan McEwan

The invasive shrub Lonicera maackii (Amur honeysuckle) is a problematic species in the eastern United States and there is growing evidence that materials from this species have toxic effects on some organisms. We used a sequence of microcosm bioassays to assess the influence of L. maackii leaf leachate on the macroinvertebrate Hyalella azteca, which is a standard aquatic organism for toxicity assessment. In a laboratory setting, H. azteca were exposed to a leaf leachate dilution series (6.25%, 12.5%, 25%, 50%, 100%) in 48-h toxicity tests. This was repeated throughout the growing season to assess the potential for changes in …


Lethal Effects Of Leaf Leachate From The Non-Native Invasive Shrub Amur Honeysuckle (Lonicera Maackii) On A Model Aquatic Organism (Hyalella Azteca), Eric B. Borth, Kevin W. Custer, Ryan W. Mcewan Jan 2018

Lethal Effects Of Leaf Leachate From The Non-Native Invasive Shrub Amur Honeysuckle (Lonicera Maackii) On A Model Aquatic Organism (Hyalella Azteca), Eric B. Borth, Kevin W. Custer, Ryan W. Mcewan

Biology Faculty Publications

The invasive shrub Lonicera maackii (Amur honeysuckle) is a problematic species in the eastern United States and there is growing evidence that materials from this species have toxic effects on some organisms. We used a sequence of microcosm bioassays to assess the influence of L. maackii leaf leachate on the macroinvertebrate Hyalella azteca, which is a standard aquatic organism for toxicity assessment. In a laboratory setting, H. azteca were exposed to a leaf leachate dilution series (6.25%, 12.5%, 25%, 50%, 100%) in 48-h toxicity tests. This was repeated throughout the growing season to assess the potential for changes in …


Interactive Effects Of Domoic Acid Allelopathy, Salinity, And Eutrophication On Estuarine Phytoplankton Community Structure, Elise Van Meerssche Jan 2018

Interactive Effects Of Domoic Acid Allelopathy, Salinity, And Eutrophication On Estuarine Phytoplankton Community Structure, Elise Van Meerssche

Theses and Dissertations

Coastal regions and estuaries are particularly sensitive to the increase in nutrient loading and river runoff, threatening the ecosystems with possible spreads in harmful algal blooms (HABs). As an example, blooms of toxic Pseudo-nitzschia species can release acute concentrations of the neurotoxin domoic acid (DA) in the water column. When ingested at concentrations higher than 20 ppm, DA can cause the death of marine birds, marine mammals and even humans. The main objectives of my research were to determine the drivers of Pseudo-nitzschia abundance and toxicity and to assess how these drivers influenced the phytoplankton community structure and DA allelopathy. …