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Articles 1 - 5 of 5
Full-Text Articles in Life Sciences
Propagation And Container Production Of The Amelanchier Spicata Complex, Gregory J. Melcher
Propagation And Container Production Of The Amelanchier Spicata Complex, Gregory J. Melcher
Electronic Theses and Dissertations
Amelanchier is a genus in the Rosaceae containing shrubs and trees indigenous to North America that possess traits valued by the horticulture industry. Amelanchier spicata (dwarf serviceberry), a heterogeneous complex of hybrids indigenous to eastern North America, has agricultural and ornamental merit with notable characteristics. White blossoms emerge in early spring, edible pomes ripen in the summer, and vibrant, orange foliage occurs in the fall. I investigated phenological and physiological factors influencing adventitious rooting of stem cuttings, the effects of nitrogen source on the development of seedlings grown in container culture, and phenotypic variation among seedlings of A. spicata from …
Expression Of A Constitutively Active Nitrate Reductase Variant In Tobacco Reduces Tobacco-Specific Nitrosamine Accumulation In Cured Leaves And Cigarette Smoke, Jianli Lu, Leichen Zhang, Ramsey S. Lewis, Lucien Bovet, Simon Goepfert, Anne M. Jack, James D. Crutchfield, Huihua Ji, Ralph E. Dewey
Expression Of A Constitutively Active Nitrate Reductase Variant In Tobacco Reduces Tobacco-Specific Nitrosamine Accumulation In Cured Leaves And Cigarette Smoke, Jianli Lu, Leichen Zhang, Ramsey S. Lewis, Lucien Bovet, Simon Goepfert, Anne M. Jack, James D. Crutchfield, Huihua Ji, Ralph E. Dewey
Kentucky Tobacco Research and Development Center Faculty Publications
Burley tobaccos (Nicotiana tabacum) display a nitrogen-use-deficiency phenotype that is associated with the accumulation of high levels of nitrate within the leaf, a trait correlated with production of a class of compounds referred to as tobacco-specific nitrosamines (TSNAs). Two TSNA species, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and N-nitrosonornicotine (NNN), have been shown to be strong carcinogens in numerous animal studies. We investigated the potential of molecular genetic strategies to lower nitrate levels in burley tobaccos by overexpressing genes encoding key enzymes of the nitrogen-assimilation pathway. Of the various constructs tested, only the expression of a constitutively active nitrate reductase (NR) …
Cooperation And Punishment In The Arbuscular Mycorrhizal Symbiosis: Implications For Resource Exchange & Biological Market Dynamics, Jerry A. Mensah
Cooperation And Punishment In The Arbuscular Mycorrhizal Symbiosis: Implications For Resource Exchange & Biological Market Dynamics, Jerry A. Mensah
Electronic Theses and Dissertations
The arbuscular mycorrhizal (AM) symbiosis is arguably the world’s most abundant and important mutualism, and brings together the roots of the majority of land plants and AM fungi to great mutual advantage. The AM symbiosis can increase the uptake of nutrients, such as phosphorus (P) and nitrogen (N), and improves the abiotic and biotic stress resistance of the host plant. AM fungi have the potential to act as biofertilizers and bioprotectors in sustainable agriculture. However, despite its significance, the mechanisms that control the resource exchange between both partners in the arbuscular mycorrhizal symbiosis are largely unknown. The main aim of …
Nutrients In The Nexus, Eric A. Davidson, Rachel L. Nifong, Richard B. Ferguson, Cheryl Palm, Deanna L. Osmond, Jill S. Baron
Nutrients In The Nexus, Eric A. Davidson, Rachel L. Nifong, Richard B. Ferguson, Cheryl Palm, Deanna L. Osmond, Jill S. Baron
Department of Agronomy and Horticulture: Faculty Publications
Synthetic nitrogen (N) fertilizer has enabled modern agriculture to greatly improve human nutrition during the twentieth century, but it has also created unintended human health and environmental pollution challenges for the twentyfirst century. Averaged globally, about half of the fertilizer-N applied to farms is removed with the crops, while the other half remains in the soil or is lost from farmers’ fields, resulting in water and air pollution. As human population continues to grow and food security improves in the developing world, the dual development goals of producing more nutritious food with low pollution will require both technological and socioeconomic …
Grain Sorghum Leaf Reflectance And Nitrogen Status, Akwasi A. Abunyewa, Richard B. Ferguson, Charles S. Wortmann, Stephen C. Mason
Grain Sorghum Leaf Reflectance And Nitrogen Status, Akwasi A. Abunyewa, Richard B. Ferguson, Charles S. Wortmann, Stephen C. Mason
Department of Agronomy and Horticulture: Faculty Publications
Nitrogen deficiency is a common but readily managed constraint to grain yield. A quick and nondestructive detection of crop N status using remote sensing could be a means to increased N use efficiency. Research was conducted in a greenhouse in 2006 at the University of Nebraska-Lincoln to establish the relationship of spectral reflectance with N status in leaves of grain sorghum, to develop indices for interpretation of the results and to predict chlorophyll content. Nitrogen stress decreased chlorophyll meter reading and leaf N content, but increased leaf and canopy reflectance. The SPAD values were significantly increased by both water and …