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Full-Text Articles in Life Sciences
Marginal Agricultural Land Identification In The Lower Mississippi Alluvial Valley, Prakash Tiwari
Marginal Agricultural Land Identification In The Lower Mississippi Alluvial Valley, Prakash Tiwari
Theses and Dissertations
This study identified marginal agricultural lands in the Lower Mississippi Alluvial Valley using crop yield predicting models. The Random Forest Regression (RFR) and Multiple Linear Regression (MLR) models were trained and validated using county-level crop yield data, climate data, soil properties, and Normalized Difference Vegetation Index (NDVI). The RFR model outperformed MLR model in estimating soybean and corn yields, with an index of agreement (d) of 0.98 and 0.96, Nash-Sutcliffe model efficiency (NSE) of 0.88 and 0.93, and root mean square error (RMSE) of 9.34% and 5.84%, respectively. Marginal agricultural lands were estimated to 26,366 hectares using cost and sales …
Evaluation For Using Expended Bioelectrochemical Systems As Soil Amendments For Improved Corn Plant Growth And A Drought Resistant Soil., Jackson Lee Sauers
Evaluation For Using Expended Bioelectrochemical Systems As Soil Amendments For Improved Corn Plant Growth And A Drought Resistant Soil., Jackson Lee Sauers
Theses and Dissertations
A long-held practice is to mix agricultural soil with a soil amendment to improve growing conditions in crops. A common soil amendment is biosolids produced from both municipal and dairy wastewater due to the macro- and micronutrients within it. Both the agricultural and wastewater industries are participating in the Circular Economy concept (CEC). Two experiments explored using expended bioelectrochemical systems (BES) that treated either synthetic dairy wastewater (DWW) or synthetic municipal wastewater (SWW) as soil amendments to improve corn plant growth when treated with three different nutrient treatments: 100%- 50%- and 0% Hoagland Nutrient Solutions. Biochar and used terracotta clay …
Reassessing Nitrogen Management For Maize Production In Mississippi, Camden Dawson Oglesby
Reassessing Nitrogen Management For Maize Production In Mississippi, Camden Dawson Oglesby
Theses and Dissertations
12 N treatments in 2020 and 11 in 2021 were replicated four times over four locations in a randomized complete block design. The first research tested the efficacy of CYG for Mississippi corn (Zea mays L.) production. The optimum N rates were calculated by fitting four models. Differences between the CYG rate and AONR were compared. AONR varied from 134 to 301 kg N ha–1 at different management levels. When we compared the AONR to the CYG rate, the CYG rate over-recommended N in 12 of the 14 possible comparisons. The second study compared different VIs, methods, and sensors at …
Sustainable Sidedress Nitrogen Applications For Early Corn And Cotton Crops Using Small Unmanned Aerial Systems, James Nolan Parker
Sustainable Sidedress Nitrogen Applications For Early Corn And Cotton Crops Using Small Unmanned Aerial Systems, James Nolan Parker
Theses and Dissertations
Nitrogen run-off from agriculture have been linked to human health problems on a global level. Large-scale conventional producers struggle to redefine themselves as sustainable because reducing nitrogen (N) inputs without justification or validation may lead to severe profit losses. Small unmanned aerial systems (sUAS) sensing may allow for decreased N runoff. Failure to address this problem will exacerbate already excessive N runoff into the Mississippi River and beyond. The purpose of this study was to reduce fertilizer N input using sUAS technology to assess crop canopy needs. In 2020 and 2021, variable rate nitrogen (VRN) side-dress N application maps were …
Quantifying The Effects Of Abiotic Stress On Early Season Growth, Development, And Physiological Characteristics In Corn, Charles Hunt Walne
Quantifying The Effects Of Abiotic Stress On Early Season Growth, Development, And Physiological Characteristics In Corn, Charles Hunt Walne
Theses and Dissertations
Corn is one of American agriculture's greatest success stories, where we have witnessed incredible increases in yield potential over the last half-century. However, abiotic stress is still the primary limiting factor preventing plants from reaching their true yield potential. In addition, agriculture is not exempt from the deleterious effects of changing weather patterns and the altered climate our world will face as time progresses. Thus, increasing our understanding of how crops interact with their environment both above and below the soil will be crucial to increasing production on a global scale while maximizing profitability at a local level. Five studies …
Evidence Of Ancient Maya Agriculture In The Bajos Surrounding Tikal, Guatemala, Adam Calvin Parker
Evidence Of Ancient Maya Agriculture In The Bajos Surrounding Tikal, Guatemala, Adam Calvin Parker
Theses and Dissertations
Current Central American agricultural practices are environmentally and economically unsustainable, yet the ancient Maya who lived in the same region thrived for thousands of years. Archaeologists have attempted to understand the factors enabling the prolonged success and ultimate collapse of the Maya societies. Some have proposed that the karst seasonal wetlands, called bajos, that border many Maya sites in the region were an influential factor in the Maya's ability to flourish. For the past decade, researchers have used carbon isotope analyses to identify areas of ancient maize agriculture at Maya archaeological sites. In this study, we collected soil samples from …
Folate Stability In Fortified Corn Masa Flour, Tortillas, And Tortilla Chips, Renee Phillips
Folate Stability In Fortified Corn Masa Flour, Tortillas, And Tortilla Chips, Renee Phillips
Theses and Dissertations
Neural tube defects (NTDs) occur at higher rates in Hispanic populations in the USA. Such populations would benefit from folic acid fortification of corn masa flour (CMF). This study evaluated folate stability in fortified CMFs and products made from the flours, tortillas and tortilla chips. There was no significant loss of folate during the six-month shelf-life of fortified tortilla CMF and tortilla chip CMF. There was a 13% loss (P < 0.05) of folate during tortilla baking and no loss during tortilla chip frying. Both tortillas and tortilla chips showed significant folate losses over the two-month shelf-life for these products, with a 17% loss in fortified tortillas and 9% loss in tortilla chips. Folate in fortified CMFs, tortillas and tortilla chips is relatively stable and comparable to the stability of folate in wheat flour and breads.
Microflora Of Traditional Mexican Corn Masa And Its Effect On Folic Acid Degradation, Stephen J. Adolphson
Microflora Of Traditional Mexican Corn Masa And Its Effect On Folic Acid Degradation, Stephen J. Adolphson
Theses and Dissertations
Many Mexican women consume inadequate amounts of folic acid. Fortification of the corn tortilla could be an effective way to help increase the folic acid levels among the Mexican population. Previous studies have shown significant folic acid losses in fortified tortilla dough (masa) as it is held before baking. This loss in folic acid could be due to degradation by lactic acid bacteria naturally present in the masa. The microflora of traditionally made nixtamalized corn masa from six tortilla mills in Guadalajara, Mexico were isolated and characterized, and their effect on folic acid content was evaluated. Isolated bacteria were identified …
Predicting Maize Yield, Nutrient Concentration And Uptake In P And K Fertilized Soils: Pressurized Hot Water And Other Alternatives To Mehlich I Extraction In Guatemala Soils, Heather Mae Hunsaker
Predicting Maize Yield, Nutrient Concentration And Uptake In P And K Fertilized Soils: Pressurized Hot Water And Other Alternatives To Mehlich I Extraction In Guatemala Soils, Heather Mae Hunsaker
Theses and Dissertations
The inaccessibility and cost of soil testing reduce effectiveness of fertilizer use on small-scale subsistence farms, and inadequate funding promotes adoption of soil tests in developing countries with minimal validation. For example, Mehlich-I extraction of phosphorus (P) currently used extensively in Guatemala may not be suitable for its broad range of soils. At least four alternatives are available but are relatively untested [Bray 1, Mehlich III, Olsen and pressurized hot water (PHW)]. Pressurized hot water is relatively simple and inexpensive, but is not yet tested against other extraction methods under variable P or potassium (K) fertilization levels. To determine whether …
Evaluation Of Forty-Two Corn (Zea Mays L.) Genotypes And Their Tolerance To Drought In Chiquimula, Servin Ardany Flores Galdámez
Evaluation Of Forty-Two Corn (Zea Mays L.) Genotypes And Their Tolerance To Drought In Chiquimula, Servin Ardany Flores Galdámez
Theses and Dissertations
The Corral de Piedra community is located in Chiquimula, Guatemala. The main agricultural activities are corn and bean production, small-scale gardens, and small animal production, such as poultry and pigs. The crop areas are predominantly located on lands with slopes between 12 and 55%, presenting low fertility conditions and poor moisture retention capabilities. In addition, local crop varieties have low productivity potentials and the winter season is characterized by poorly distributed and erratic periods of rain. The Benson Institute introduced a technology transfer model to increase and diversify agricultural production, while preserving current natural resources. An integral part of this …
Evaluation Of 4 Small Doses Of Fertilizer In Growing Maize (Zea Mays L.) In Two Communities Of San Juan Ermita, Chiquimula, Victor Estuardo Villalta Garcia
Evaluation Of 4 Small Doses Of Fertilizer In Growing Maize (Zea Mays L.) In Two Communities Of San Juan Ermita, Chiquimula, Victor Estuardo Villalta Garcia
Theses and Dissertations
Corral de Piedra and Salitron are two communities located in the municipality of San Juan Ermita, which is in the department of Chiquimula, Guatemala. In both communities, the land has very sloped topography with slope grades ranging from 12 to 55%. Agriculture is the main production activity with corn (Zea mays L.) and beans (Phaseolus vulgaris) being the crops of greatest economic importance. These crops are planted through a system of sequential association commonly called relay. First, corn is planted at the beginning of the rainy season (May or June). Once it has completed its reproductive cycle, beans are planted …