College of Agriculture & Natural Resources

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The collections in this community comprise faculty research works, as well as graduate theses and dissertations.

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20 Recommended Vegetable Crops for School Container Gardens: Classification and Characteristics
(University of Maryland Extension, 2010-01) Traunfeld, Jon; Smith, Erica
This chart lists plants that can be harvested in spring or fall by name, providing information about edible parts, container depth, time to plant/harvest, difficulty to grow, flavor, and nutrition.
2014 Changes for Organic Crop Insurance
(2014-02) Goeringer, L. Paul; Lynch, Lori
2014 Farm Bill Dairy Provisions
(2014-08) Connelly, Steve
Provides an overview of the risk management options that will be available for dairy producers under the 2014 Farm Bill
2014 Farm Bill Educational Tools
(2014-08) Connelly, Steve
This presentation gives an overview of the producer tools that will be available to aid in the decision making process.
2014 Farm Bill Makes Changes to the Noninsured Crop Disaster Assistance Program
(2015-09) Goeringer, Paul; Leathers, Howard
The Noninsured Crop Disaster Assistance Program (NAP) was established in 1994 and administered by USDA’s Farm Service Agency (FSA). NAP is a risk management tool for those producers growing crops not currently covered by a crop insurance product. The 2014 Farm Bill reauthorized NAP and made some dramatic changes to the program. NAP now offers coverage from the 50-percent level to the 65-percent level with producers able to buy-up coverage in 5-percent increments at up to 100 percent of the established market price. Prior to the 2014 Farm Bill, NAP had only allowed coverage at the 50-percent level and 55 percent of the established market price of the crop.
2014 Farm Bill Training
(2014-08) Wevodau, Bob
This presentation was presented under by the 2014 Farm Bill Workshops across MD. This presentation provides an overview of the commodity programs in the new bill.
2014 Legal Services Directory
(2014-04) Agricultural Law Section, Maryland State Bar Association
2015-16 Legal Services Directory
(2015-06) Agriculture Law Section, Maryland State Bar Association
Directory of members as of June 2015 of the Maryland State Bar Association's Agriculture Law Section.
2016 USDA Crop Insurance Update
(2016-09-13) Alston, Michael
2019 Market Facilitation Program Available to Assist Producers Trade Disputes
(2019-08-04) Millet-Williams, Nerice; Goeringer, Paul
The U.S. Department of Agriculture (USDA) Farm Service Agency (FSA) established the Market Facilitation Program (MFP) under Section 5 of the Commodity Credit Corporation (CCC) Charter Act in 2018. This section authorizes CCC to assist in the disposition of surplus commodities and to increase the domestic consumption of agricultural commodities by expanding or aiding in the expansion of domestic markets or by developing or aiding in the development of new and additional markets, marketing facilities and uses for such commodities. MFP provides direct payments to producers of specific products impacted by foreign tariffs. This program has been updated for 2019 to continue to assist growers impacted by trade disputes.
A Comparison of Irrigation-Water Containment Methods and Management Strategies Between Two Ornamental Production Systems to Minimize Water Security Threats
(MDPI, 2019-12-03) Ristvey, Andrew G.; Belayneh, Bruk E.; Lea-Cox, John D.
Water security in ornamental plant production systems is vital for maintaining profitability. Expensive, complicated, or potentially dangerous treatment systems, together with skilled labor, is often necessary to ensure water quality and plant health. Two contrasting commercial ornamental crop production systems in a mesic region are compared, providing insight into the various strategies employed using irrigation-water containment and treatment systems. The first is a greenhouse/outdoor container operation which grows annual ornamental plants throughout the year using irrigation booms, drip emitters, and/or ebb and flow systems depending on the crop, container size, and/or stage of growth. The operation contains and recycles 50–75% of applied water through a system of underground cisterns, using a recycling reservoir and a newly constructed 0.25 ha slow-sand filtration (SSF) unit. Groundwater provides additional water when needed. Water quantity is not a problem in this operation, but disease and water quality issues, including agrochemicals, are of potential concern. The second is a perennial-plant nursery which propagates cuttings and produces field-grown trees and containerized plants. It has a series of containment/recycling reservoirs that capture rainwater and irrigation return water, together with wells of limited output. Water quantity is a more important issue for this nursery, but poor water quality has had some negative economic effects. Irrigation return water is filtered and sanitized with chlorine gas before being applied to plants via overhead and micro-irrigation systems. The agrochemical paclobutrazol was monitored for one year in the first operation and plant pathogens were qualified and quantified over two seasons for both production systems. The two operations employ very different water treatment systems based on their access to water, growing methods, land topography, and capital investment. Each operation has experienced different water quantity and quality vulnerabilities, and has addressed these threats using a variety of technologies and management techniques to reduce their impacts.
A Linear Surface Epitope in a Proline-Rich Region of ORF3 Product of Genotype 1 Hepatitis E Virus
(MDPI, 2016-08-18) Yang, Yonglin; Lin, Shaoli; Nan, Yuchen; Ma, Zexu; Yang, Liping; Zhang, Yanjin
Hepatitis E virus (HEV) is one of the viral pathogens causing hepatitis in humans. HEV open reading frame 3 (ORF3) encodes a small multifunctional protein (VP13), which is essential for HEV infection. In this study, a linear epitope was identified in a polyproline (PXXP) motif from VP13 of genotype 1 HEV by using a monoclonal antibody. The epitope was detected in enzyme-linked immunosorbent assay (ELISA), immunoblotting and immunofluorescence assays. Epitope mapping showed that the epitope locates in a proline-rich region containing a PXXP motif in amino acid residues 66-75 of VP13. The epitope was also detected in HEV-infected liver cells and reacted with genotype 1-specific antibodies in an HEV-positive human serum sample. The results demonstrated that the epitope in the PXXP motif of the genotype 1 VP13 is linear and surface-oriented, which should facilitate in-depth studies on the viral protein and HEV biology.
A Machine Learning Model for Food Source Attribution of Listeria monocytogenes
(MDPI, 2022-06-16) Tanui, Collins K.; Benefo, Edmund O.; Karanth, Shraddha; Pradhan, Abani K.
Despite its low morbidity, listeriosis has a high mortality rate due to the severity of its clinical manifestations. The source of human listeriosis is often unclear. In this study, we investigate the ability of machine learning to predict the food source from which clinical Listeria monocytogenes isolates originated. Four machine learning classification algorithms were trained on core genome multilocus sequence typing data of 1212 L. monocytogenes isolates from various food sources. The average accuracies of random forest, support vector machine radial kernel, stochastic gradient boosting, and logit boost were found to be 0.72, 0.61, 0.7, and 0.73, respectively. Logit boost showed the best performance and was used in model testing on 154 L. monocytogenes clinical isolates. The model attributed 17.5 % of human clinical cases to dairy, 32.5% to fruits, 14.3% to leafy greens, 9.7% to meat, 4.6% to poultry, and 18.8% to vegetables. The final model also provided us with genetic features that were predictive of specific sources. Thus, this combination of genomic data and machine learning-based models can greatly enhance our ability to track L. monocytogenes from different food sources.
A proximity biotinylation assay with a host protein bait reveals multiple factors modulating enterovirus replication
(PLoS, 2022-10-28) Moghimi, Seyedehmahsa; Viktorova, Ekaterina G.; Gabaglio, Samuel; Zimina, Anna; Budnik, Bogdan; Wynn, Bridge G.; Sztul, Elizabeth; Belov, George A.
As ultimate parasites, viruses depend on host factors for every step of their life cycle. On the other hand, cells evolved multiple mechanisms of detecting and interfering with viral replication. Yet, our understanding of the complex ensembles of pro- and anti-viral factors is very limited in virtually every virus-cell system. Here we investigated the proteins recruited to the replication organelles of poliovirus, a representative of the genus Enterovirus of the Picornaviridae family. We took advantage of a strict dependence of enterovirus replication on a host protein GBF1, and established a stable cell line expressing a truncated GBF1 fused to APEX2 peroxidase that effectively supported viral replication upon inhibition of the endogenous GBF1. This construct biotinylated multiple host and viral proteins on the replication organelles. Among the viral proteins, the polyprotein cleavage intermediates were overrepresented, suggesting that the GBF1 environment is linked to viral polyprotein processing. The proteomics characterization of biotinylated host proteins identified multiple proteins previously associated with enterovirus replication, as well as more than 200 new factors recruited to the replication organelles. RNA metabolism proteins, many of which normally localize in the nucleus, constituted the largest group, underscoring the massive release of nuclear factors into the cytoplasm of infected cells and their involvement in viral replication. Functional analysis of several newly identified proteins revealed both pro- and anti-viral factors, including a novel component of infection-induced stress granules. Depletion of these proteins similarly affected the replication of diverse enteroviruses indicating broad conservation of the replication mechanisms. Thus, our data significantly expand the knowledge of the composition of enterovirus replication organelles, provide new insights into viral replication, and offer a novel resource for identifying targets for anti-viral interventions.
Absorption and metabolism of 3-MCPD 1-monopalmitate in rats
(2017) Gao, Boyan; Yu, Liangli (Lucy); Food Science; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
Fatty acid esters of 3-monochloropropane 1,2-diol (3-MCPD esters) are a group of potential chemical toxicants. Their toxic effects primarily include nephrotoxicity and hepatotoxicity. To understand the toxic mechanisms of 3-MCPD esters, one of the key points is to advance the understanding of their metabolic mechanisms in vivo. This dissertation investigated 1) the absorption and kinetics of 3-MCPD 1-monopalmitate in rats, 2) the possible metabolites of 3- MCPD 1-monopalmitate after oral administration to rats, and 3) the possible metabolic pathways of 3-MCPD 1-monopalmitate in vivo. The greatest concentration of 3-MCPD 1-monopalmitate in the plasma was 873.72 ng/mL (Cmax) at about 1.67 hours (Tmax) after oral administration. The concentration of 3-MCPD 1-monopalmitate reduced to half after 3.42 hours (t1/2). No 3-MCPD 1-monopalmitate could be detected after 4 hours, which was its mean resident time (MRT). The area under curve (AUC) for 3-MCPD 1-monopalmitate in rat plasma was 1676.15 h.ng/mL, which represented the maximum amount of 3-MCPD 1-monopalmitate absorbed into plasma under the testing conditions. Beside, 39 possible metabolites were tentatively identified in the liver, kidney, testis, brain, plasma and urine samples at 6, 12, 24 and 48 hours after oral administration of 3-MCPD 1-monopalmitate to rats. In addition, five major metabolic pathways of 3-MCPD esters were derivate to evaluate their metabolic conditions in vivo. These results can greatly enhance the understanding about the absorption, distribution and metabolism conditions of 3-MCPD esters in vivo, and promote further research about the biological actions of 3-MCPD esters.
Absorption, Excretion, and Transformation of Individual Anthocyanins in Rats
(2004-08-06) He, Jian; Giusti, Monica M; Magnuson, Bernadene A; Food Science; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
Anthocyanins are polyphenolics responsible for most red to purple colors in plants. Human consumption is increasing because of their potential health benefits and use as natural colorants. However, their absorption and metabolism are not well characterized. We compared anthocyanin absorption and excretion in rats receiving chokeberry, bilberry or grape enriched diet (4g anthocyanin/kg) for 13 weeks. Traces of anthocyanins and metabolites were detected in plasma. In urine, intact anthocyanins and methylated derivatives (~ 24, 8, 15 mg cy-3-gla equivalent/L urine for chokeberry, bilberry, grape) were found. High metabolite concentration suggested accumulation of methylated anthocyanins in tissue. Fecal anthocyanin extraction was maximized with aqueous methanol (60%). Anthocyanin concentration in feces ranged from 0.7 to 2g anthocyanin/kg, similar to cecal content. In the gut, anthocyanin degradation was high for glucosides, moderate for galactosides and negligible for arabinosides and xylosides. Both, glycosylation and acylation seemed to affect the bioavailability of anthocyanins in vivo.
Acclimation and Compensating Metabolite Responses to UV-B Radiation in Natural and Transgenic Populus spp. Defective in Lignin Biosynthesis
(MDPI, 2022-08-20) Wong, Tiffany M.; Sullivan, Joe H.; Eisenstein, Edward
Plants have evolved to protect leaf mesophyll tissue from damage caused by UV-B radiation by producing an array of UV-absorbing secondary metabolites. Flavonoids (phenolic glycosides) and sinapate esters (hydroxycinnamates) have been implicated as UV-B protective compounds because of the accumulation in the leaf epidermis and the strong absorption in the wavelengths corresponding to UV. Environmental adaptations by plants also generate a suite of responses for protection against damage caused by UV-B radiation, with plants from high elevations or low latitudes generally displaying greater adaptation or tolerance to UV-B radiation. In an effort to explore the relationships between plant lignin levels and composition, the origin of growth elevation, and the hierarchical synthesis of UV-screening compounds, a collection of natural variants as well as transgenic Populus spp. were examined for sensitivity or acclimation to UV-B radiation under greenhouse and laboratory conditions. Noninvasive, ecophysiological measurements using epidermal transmittance and chlorophyll fluorescence as well as metabolite measurements using UPLC-MS generally revealed that the synthesis of anthocyanins, flavonoids, and lignin precursors are increased in Populus upon moderate to high UV-B treatment. However, poplar plants with genetic modifications that affect lignin biosynthesis, or natural variants with altered lignin levels and compositions, displayed complex changes in phenylpropanoid metabolites. A balance between elevated metabolic precursors to protective phenylpropanoids and increased biosynthesis of these anthocyanins, flavonoids, and lignin is proposed to play a role in the acclimation of Populus to UV-B radiation and may provide a useful tool in engineering plants as improved bioenergy feedstocks.
Acid Modification of Psyllium
(2008) Pei, Xiaoyin; Yu, Liangli; Food Science; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
Psyllium, a type of dietary fiber, has been shown to have various health benefits including cholesterol lowering, hypoglycemic, cancer prevention, and laxative effects. However, due to its extremely strong water-holding and gel-forming capacities, incorporation of psyllium into food products on the required amount per serving for health claim is difficult. This study evaluated the effect of acid treatment on water up-taking, swelling, gelling and bile acid binding capacities of psyllium samples. The acid treatments were conducted at different reaction temperatures (25, 37.5, and 50 °C) with different psyllium - solvent ratios (1:2.5, 1:5, 1:7.5, and 1:10 g/mL). The result showed that reaction temperature influenced the effectiveness of acid treatment on physical/chemical properties of psyllium samples significantly, while effects of different psyllium - solvent ratios were not significant. This implicated the acid modification at a high temperature might be a possible method to improve the physical/chemical properties of psyllium for incorporation in food.
Activating a 60's Modernist Plaza Using the Principles of Human Scale Design: Re-imagining HUD Plaza
(2021) Velez-Lopez, Sebastian; Sullivan, Jack; Plant Science and Landscape Architecture (PSLA); Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
Population growth has increased rapidly across many large American cities in the last 20 years. The growing population generates a need for quality public open space, but it also increases the development of housing making land increase drastically in value, making it harder for municipalities to acquire land for public open space projects. One strategy that cities can use to address this issue, is to leverage existing public spaces that are currently underutilized. This project explores the contemporary principles of public space and human scale design through a review of the existing literature. The principles gathered from the literature, are demonstrated by using them as the basis for re-imagining an underutilized urban public space. The project establishes a link between the research on public space design and practice, providing an example of how it can be used to create innovative ways to better utilize our existing public spaces.
Activation of the RpoN-RpoS regulatory pathway during the enzootic life cycle of Borrelia burgdorferi
(Springer Nature, 2012-03-23) Ouyang, Zhiming; Narasimhan, Sukanya; Neelakanta, Girish; Kumar, Manish; Pal, Utpal; Fikrig, Erol; Norgard, Michael V
The maintenance of Borrelia burgdorferi in its complex tick-mammalian enzootic life cycle is dependent on the organism's adaptation to its diverse niches. To this end, the RpoN-RpoS regulatory pathway in B. burgdorferi plays a central role in microbial survival and Lyme disease pathogenesis by up- or down-regulating the expression of a number of virulence-associated outer membrane lipoproteins in response to key environmental stimuli. Whereas a number of studies have reported on the expression of RpoS and its target genes, a more comprehensive understanding of when activation of the RpoN-RpoS pathway occurs, and when induction of the pathway is most relevant to specific stage(s) in the life cycle of B. burgdorferi, has been lacking. Herein, we examined the expression of rpoS and key lipoprotein genes regulated by RpoS, including ospC, ospA, and dbpA, throughout the entire tick-mammal infectious cycle of B. burgdorferi. Our data revealed that transcription of rpoS, ospC, and dbpA is highly induced in nymphal ticks when taking a blood meal. The RpoN-RpoS pathway remains active during the mammalian infection phase, as indicated by the sustained transcription of rpoS and dbpA in B. burgdorferi within mouse tissues following borrelial dissemination. However, dbpA transcription levels in fed larvae and intermolt larvae suggested that an additional layer of control likely is involved in the expression of the dbpBA operon. Our results also provide further evidence for the downregulation of ospA expression during mammalian infection, and the repression of ospC at later phases of mammalian infection by B. burgdorferi. Our study demonstrates that the RpoN-RpoS regulatory pathway is initially activated during the tick transmission of B. burgdorferi to its mammalian host, and is sustained during mammalian infection.

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