Microbial Remediation of Fragipan
Academic Level at Time of Presentation
Senior
Major
Agricultural Science/Agronomy
List all Project Mentors & Advisor(s)
Dr. Iin Handayani
Presentation Format
Oral Presentation
Abstract/Description
The fragipan layer in the soil is a naturally occurring subsurface layer that restricts water percolation as well as inhibits root growth. A fragipan layer can be found almost ubiquitously across Southwestern Kentucky. This limits how agriculturalists manage soils in this area. It has been recently discovered by the University of Kentucky that annual ryegrass roots produce 3,4 dihydroxyphenylpropionic acid (DHPPA) that reacts with this hardpan to weaken the layer. Certain bacteria, such as Escherichia coli, Lactobacilli, and Bifidobacteria can also synthesize DHPPA through a breakdown process of chlorogenic acid. This reaction typically happens in the human digestive tract. The objective of this study is to find a biological solution to fragipan remediation. This experiment consists of four treatments, each replicated three times. Soil samples from the fragipan layer will be taken into the lab where they are treated in the following ways: control (no treatment) (T0), various bacteria species with a balanced ratio of tea and coffee grounds (T1), Annual ryegrass alone (T2), various bacteria species with tea and coffee grounds and annual ryegrass (T3). T3 will also be applied on a Bt soil horizon sample to evaluate the effects on fragipan alone vs the whole B horizon. Treatments will be applied periodically to ensure that bacterial populations remain adequate and active. The samples are to be weighed dry biweekly and a visual analysis should be done to monitor any types of major cracking or degradation. All of the data will be statistically analyzed using Microsoft Excel. The results of this study would greatly affect how growers manage fragipan in their soil in Kentucky, as well as improve soil drainage and crop production.
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Honors College Senior Thesis Presentations
Microbial Remediation of Fragipan
The fragipan layer in the soil is a naturally occurring subsurface layer that restricts water percolation as well as inhibits root growth. A fragipan layer can be found almost ubiquitously across Southwestern Kentucky. This limits how agriculturalists manage soils in this area. It has been recently discovered by the University of Kentucky that annual ryegrass roots produce 3,4 dihydroxyphenylpropionic acid (DHPPA) that reacts with this hardpan to weaken the layer. Certain bacteria, such as Escherichia coli, Lactobacilli, and Bifidobacteria can also synthesize DHPPA through a breakdown process of chlorogenic acid. This reaction typically happens in the human digestive tract. The objective of this study is to find a biological solution to fragipan remediation. This experiment consists of four treatments, each replicated three times. Soil samples from the fragipan layer will be taken into the lab where they are treated in the following ways: control (no treatment) (T0), various bacteria species with a balanced ratio of tea and coffee grounds (T1), Annual ryegrass alone (T2), various bacteria species with tea and coffee grounds and annual ryegrass (T3). T3 will also be applied on a Bt soil horizon sample to evaluate the effects on fragipan alone vs the whole B horizon. Treatments will be applied periodically to ensure that bacterial populations remain adequate and active. The samples are to be weighed dry biweekly and a visual analysis should be done to monitor any types of major cracking or degradation. All of the data will be statistically analyzed using Microsoft Excel. The results of this study would greatly affect how growers manage fragipan in their soil in Kentucky, as well as improve soil drainage and crop production.