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Full-Text Articles in Life Sciences
Impact Of Climate Variations On Soybean Yield In Eastern Arkansas: 1960-2014, J. W. Magugu, S. Feng, Q. Huang, K. Luthra
Impact Of Climate Variations On Soybean Yield In Eastern Arkansas: 1960-2014, J. W. Magugu, S. Feng, Q. Huang, K. Luthra
Journal of the Arkansas Academy of Science
Climate is the major factor affecting crop production; therefore, various agro-meteorological indicators have been frequently used to evaluate the impact of climate on crop production. In this study, we examined the temporal variations of agrometeorological indicators (growing degree days, total precipitation, dry spells and drought indices) during 1960-2014 and their impact on soybean yields in East Arkansas. Results show an increasing trend in growing degree days (GDDs) and dry spells, though the total precipitation during the soybean growing season remained nearly unchanged during the study period. Generally, GDDs and dry spells show a strong correlation with yields. We also evaluated …
Nutrient Competition Between Algae And Juncus Effusus In The Lake Fayetteville Artificial Spiral Wetland, Toryn Jones, Thad Scott
Nutrient Competition Between Algae And Juncus Effusus In The Lake Fayetteville Artificial Spiral Wetland, Toryn Jones, Thad Scott
Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences
There is insufficient research focusing exclusively on how nutrient competition between algae and wetland macrophytes affects the growth of these species. This study examined the relationship between nutrient concentrations (N and P), algal concentrations, and the growth of Juncus effusus. Juncus effusus growth in the Lake Fayetteville artificial spiral wetland was monitored over a four month period during the prime growing season. Eighteen plants were taken from the wetland and replanted in 1 of 6 treatments: plant-only, algae-only, combined, plant-only +supplement, algaeonly +supplement, or combined +supplement. The algae and combined environments received an inoculation of algae, and the +supplement treatments …
Synthesis, Characterization, And Properties Of Mononuclear And Dinuclear Ruthenium(Ii) Complexes Containing Phenanthroline And Chlorophenanthroline, Anwar A. Bhuiyan, X. Du
Synthesis, Characterization, And Properties Of Mononuclear And Dinuclear Ruthenium(Ii) Complexes Containing Phenanthroline And Chlorophenanthroline, Anwar A. Bhuiyan, X. Du
Journal of the Arkansas Academy of Science
The study of photophysical and photochemical properties of ruthenium complexes is of great interest for fundamental practical reasons. Ruthenium complexes have been investigated for use in artificial photosynthesis. This paper deals with the synthesis and spectroscopic investigation of custom-designed ruthenium complexes containing phenanthroline and chloro-phenanthroline ligands. These complexes maybe useful for biological electron-transfer studies. The heteroleptic ruthenium monomer complex Ru(phen)2(Cl-phen) (where phen = 1,10-phenanthroline and Cl-phen=5-chloro-1,10-phenanthroline) was prepared in a two-step procedure previously developed in our laboratory. This monomer complex was used to prepare the ruthenium homometallic dimer complex, (phen)2Ru(phen-phen)Ru(phen)2, by utilizing the Ni-catalyzed coupling reaction. Both complexes were purified …
Understanding Floristic Diversity Though A Database Of Greene County Specimens, K. M. Harris, M. B. Foard, T. D. Marsico
Understanding Floristic Diversity Though A Database Of Greene County Specimens, K. M. Harris, M. B. Foard, T. D. Marsico
Journal of the Arkansas Academy of Science
We present a floristic list of Greene County, Arkansas, based on accessioned collections from the Arkansas State University Herbarium (STAR). Currently, there are 1569 specimens representing 540 taxa from Greene County in STAR. Using the USDA Plants Database, plant species were analyzed according to whether or not they are native to the state as well as whether or not they have been previously documented as species occurring in the county. Having analyzed all the Greene County collections from STAR, we found 225 previously undocumented species. The data suggest that most of the specimens in the STAR collection were found in …
Comparative Leaf Decomposition Rates Including A Non-Native Species In An Urban Ozark Stream, Sarah E. Lewis, Arthur V. Brown
Comparative Leaf Decomposition Rates Including A Non-Native Species In An Urban Ozark Stream, Sarah E. Lewis, Arthur V. Brown
Journal of the Arkansas Academy of Science
Leaf decomposition of three species of native Ozark vegetation was compared to that of one nonnative invasive species. Leaves were placed in an urban gravel-bed stream for 23 days. Changes in mass and condition of the leaves were assessed along with stream temperature, flow, width, depth and discharge. Species native to Eastern North American forests were sycamore (Platanus occidentalis), dogwood (Cornus florida), and redbud (Cercis canadensis). The nonnative species, Japanese (Amur) honeysuckle (Lonicera maackii) comprised approximately 80% of the understory vegetation within the riparian zone of the study reach. After 23 days, Sycamore lost 24.6% mass, dogwood lost 30%, redbud …
Analysis Of The Accase Mutation Profile Of Italian Ryegrass (Lolium Perenne Ssp. Multiflorum) Accessions Resistant To Accase Inhibitors, Thomas Stark
Inquiry: The University of Arkansas Undergraduate Research Journal
Lolium perenne ssp. multiflorum (Italian ryegrass) resistant to ACCase inhibiting herbicides has been reported in many wheat producing counties across Arkansas. Resistance is believed to be the result of point mutations creating amino acid substitutions in the CT domain of the plastidic ACCase gene. This study explores the occurrence of mutations in the ACCase gene of ryegrass populations. Plant material was collected and DNA was extracted from 10 Arkansas ryegrass populations. Six of the populations were known to be resistant to the ACCase inhibitor diclofop-methyl, while the remaining four populations were known to be susceptible to diclofop-methyl. Two highly conserved …
Letter From The Dean, Lalit Verma
Letter From The Dean, Lalit Verma
Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences
No abstract provided.
Algae In Agricultural Fields From St. Francis County, Arkansas, T. Smith
Algae In Agricultural Fields From St. Francis County, Arkansas, T. Smith
Journal of the Arkansas Academy of Science
On August 9th, 2007, two agriculture fields (rice and sorghum fields) were sampled for freshwater algae in St. Francis County. The purpose of this study was to document the algal species in the rice and sorghum fields and compare the similarities of species composition. There were a total of 53 species identified. Overall, diatoms and cyanobacteria were equally dominant with both represented by 21 species (39.6% of the total) and 11 green algal species (20.8%) were present. The sorghum field was dominated by Chlorogloeopsis fritschii and Chroococcus limneticus, while Anabeana cylindrica was abundant in the rice field.
Comparison Of Instrumental Methods For Measuring Seed Hardness Of Food-Grade Soybean, Mioko Tamura, Bo Zhang, Joyce Berger-Doyle, Pengyin Chen
Comparison Of Instrumental Methods For Measuring Seed Hardness Of Food-Grade Soybean, Mioko Tamura, Bo Zhang, Joyce Berger-Doyle, Pengyin Chen
Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences
Seed hardness is an important factor in determining soybean suitability for natto production. There is no established methodology for testing seed texture of soybeans. The objective of this study was to develop an efficient method by examining different instruments and seed parameters that could be potentially used for testing soybean seed hardness. Five food-grade soybean genotypes with different seed sizes were used to determine seed hardness and water-absorption capacity. Water absorption capacity was expressed by swell ratios for seed weight, seed dimension, and volume of water changes before and after soaking. Seed hardness test was conducted by a one-bite method …
Tungoil Tree (Aleurites Fordii Hemsl.) (Euphorbiaceae): New To The Arkansas Flora, Brett Serviss, Nicole Freeman, Joslyn Hernandez, Allen Leible, Chris Talley
Tungoil Tree (Aleurites Fordii Hemsl.) (Euphorbiaceae): New To The Arkansas Flora, Brett Serviss, Nicole Freeman, Joslyn Hernandez, Allen Leible, Chris Talley
Journal of the Arkansas Academy of Science
No abstract provided.
Negundo Chaste Tree (Vitex Negundo L.) (Verbenaceae): New To The Arkansas Flora, Brett Serviss, Nicole Freeman, Joslyn Hernandez, Allen Leible, Chris Talley, Brent Baker
Negundo Chaste Tree (Vitex Negundo L.) (Verbenaceae): New To The Arkansas Flora, Brett Serviss, Nicole Freeman, Joslyn Hernandez, Allen Leible, Chris Talley, Brent Baker
Journal of the Arkansas Academy of Science
No abstract provided.
Discovery Of A Second Record Of Seaside Heliotrope (Heliotropilum Curassavicum L.) (Boraginaceae) In Arkansas, C. Renn Tumlison, Brett Serviss
Discovery Of A Second Record Of Seaside Heliotrope (Heliotropilum Curassavicum L.) (Boraginaceae) In Arkansas, C. Renn Tumlison, Brett Serviss
Journal of the Arkansas Academy of Science
No abstract provided.
Characterization Of Bacteriophages Of Pseudomonas Syringae Pv. Tomato, Sara E. Prior, Amanda J. Andrews, Russell O. Nordeen
Characterization Of Bacteriophages Of Pseudomonas Syringae Pv. Tomato, Sara E. Prior, Amanda J. Andrews, Russell O. Nordeen
Journal of the Arkansas Academy of Science
Bacteriophages from supernatants of the plant pathogenic bacteria Pseudomonas syringae pv. tomato (P. tomato) were isolated, enriched, and purified by density block centrifugation in cesium chloride (CsCl) step gradients. The DNA from purified phage was isolated and digested with the restriction endonucleases EcoRl or HindIII. Three different DNA fingerprint patterns were determined indicating 3 unique phage isolates. Genome sizes of the phage ranged from 40 to 52 kilobases (kB). Buoyant densities of phage particles in CsCI varied from 1.36 to 1.51 glml. Electron microscopy revealed a single morphological type with an elongated polyhedral head and a long tail indicating the …
Evaluation Of Water-Retention Ability Of Eastern Arkansas Prairie And Agricultural Soil, Maria L. Barrenechea, Kristofor R. Brye
Evaluation Of Water-Retention Ability Of Eastern Arkansas Prairie And Agricultural Soil, Maria L. Barrenechea, Kristofor R. Brye
Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences
Agricultural land use affects soil physical properties, such as bulk density, water content, organic matter content, and soil structure; all of which in turn affect ecosystem productivity. The objective of this study was to evaluate the effects of: 1) time since aboveground biomass has been removed by haying (i.e., 0 vs. 23 years), and 2) land use (i.e., undisturbed tallgrass prairie vs. cultivated agriculture) on water-retention characteristics in a silt-loam soil of the Grand Prairie region of eastern Arkansas. Soil samples were collected from the 0- to 10-cm depth and were wetted with varying amounts of distillated water to create …
Adventitious Shoot Propagation And Cultural Inputs In Nursery Production Of A Primocane-Fruiting Blackberry Selection, Kimberley Dennis, John R. Clark, James A. Robbins
Adventitious Shoot Propagation And Cultural Inputs In Nursery Production Of A Primocane-Fruiting Blackberry Selection, Kimberley Dennis, John R. Clark, James A. Robbins
Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences
Studies were conducted from January to October 2005 to determine the effect of root-cutting length on adventitious shoot yield and the management practices necessary to produce nurseryquality primocane-fruiting blackberry plants. The first portion of the study measured the average number of shoots produced from 7.6 cm- and 15.2 cm-long root cuttings of APF-44 blackberry—a primocane-fruiting genotype from the University of Arkansas breeding program. Cuttings were forced in a shallow bin containing a soilless potting medium. The average number of shoots per root cutting from 7.6 cm- and 15.2 cm- long root cuttings averaged 1.6 and 2.7 shoots per root cutting, …
Vascular Plant Species Inventory Of Richardson Bottoms Wildlife Viewing Area, Travis D. Marsico
Vascular Plant Species Inventory Of Richardson Bottoms Wildlife Viewing Area, Travis D. Marsico
Journal of the Arkansas Academy of Science
No abstract provided.
Aerobic Stability Of Heat And Orchardgrass Round-Bale Silage, Robert T. Rhein, Wayne K. Coblentz, Charles F. Rosenkrans Jr., D. Wayne Kellog
Aerobic Stability Of Heat And Orchardgrass Round-Bale Silage, Robert T. Rhein, Wayne K. Coblentz, Charles F. Rosenkrans Jr., D. Wayne Kellog
Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences
In Arkansas, silage is typically stored as balage in long rows of round bales wrapped in plastic film. It is important to evaluate the aerobic stability of this fermented forage when it is exposed to air, especially during the winter months when most of it is fed to livestock or sold as a cash crop. Two types of forage, orchardgrass (Dactylis glomerata) and wheat (Triticum aestivum), were harvested in May 2002 and stored as balage. Twenty-one bales of each balage type were unwrapped and exposed to air on 10 Dec. 2002 for 0, 2, 4, 8, 16, 24, or 32 …
Chitosanase May Enhance Anti-Fungal Defense Responses In Transgenic Tobacco, Bill L. Hendrix
Chitosanase May Enhance Anti-Fungal Defense Responses In Transgenic Tobacco, Bill L. Hendrix
Inquiry: The University of Arkansas Undergraduate Research Journal
Fungicides are expensive, dangerous, and can be harmful to the environment, but they are often necessary for profitable farming operations. New technologies may soon allow farmers to replace these chemicals with genetically engineered plants producing antifungal enzymes that degrade fungal cell walls. To explore this option, a Paenbacillus chitosanase gene was cloned, sequenced, and modified for plant expression. The modified gene was delivered to tobacco (Nicotiana tabacum L cv. Xanthine) leaf disks via Agrobacterium tumenfaciens-mediated transformation. The putative GMOs were tested for transgene integration, transcription, and translation. Confirmed transformants were then screened for enhanced responses to a Rhizoctonia solani cell …
The Role Of Natural Calcium Oxalate Crystals In Plant Defense Against Chewing Insects, Sarah J. Doege
The Role Of Natural Calcium Oxalate Crystals In Plant Defense Against Chewing Insects, Sarah J. Doege
Inquiry: The University of Arkansas Undergraduate Research Journal
Calcium oxalate is the most abundant insoluble mineral found in plants and it is common among many plant families. Calcium oxalate crystals in plants can appear as irregular rectangles, spiked balls, or needles. The formidable appearance of these crystals has lead to speculation that they might serve as a form of pest control by deterring chewing insects. We utilized mutant plant lines to assess the effects of plant calcium oxalate crystals on the survival and feeding habits of chewing insects. We have taken advantage of calcium oxalate-deficient (cod) mutants of the barrel medic, Medicago truncatula Calcium oxalate crystals accumulate in …
Expression Patterns Of Novel Wound-Inducible Plant Genes In Medicago Truncatula, Mandy M. Cox, Kenneth L. Korth
Expression Patterns Of Novel Wound-Inducible Plant Genes In Medicago Truncatula, Mandy M. Cox, Kenneth L. Korth
Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences
Terpenoids are an important class of defensive compounds that can accumulate in plants after pathogen infection or injury by chewing insects. Clones encoding putative terpene synthases and an oxidosqualene synthase, isolated from insect-damaged Medicagotruncatula leaves, were selected from an expressed sequence tag (EST) database. The cDNA clones were used as radiolabeled probes to analyze gene expression in leaves treated by known factors that can trigger a defense response in plants. Transcript levels for all of the genes examined increased in response to artificial wounding, insect herbivory, and methyl jasmonate (meJA) treatments, whereas salicylic acid (SA) and glucose oxidase (GOX) had …
Fire Effects On Three Trophic Levels In A Central Arkansas Grassland, Laura Skelton, Amy Polk, Brenna C. Fitzgerald, Matthew D. Moran
Fire Effects On Three Trophic Levels In A Central Arkansas Grassland, Laura Skelton, Amy Polk, Brenna C. Fitzgerald, Matthew D. Moran
Journal of the Arkansas Academy of Science
We studied the effect of a late growing-season fire on the plant and foliar arthropod communities in a naturally occurring grassland. In central Arkansas, these grasslands are common on south-facing slopes where shallow soils and hot/dry weather conditions during the summer cannot support the growth of a forest community. Patches of grassland were burned in the autumn (4 November, late growing season), often the time of natural fires in Arkansas, and compared to unburned areas. Fire increased the biomass of forbs and decreased the biomass of grasses, although overall biomass was not different between treatments. Among the foliar arthropods, herbivores …
Characterization Of Wound-Inducible Genes Encoding Enzymes For Terpenoid Biosynthesis In Medicago Truncatula, Mandy M. Cox
Characterization Of Wound-Inducible Genes Encoding Enzymes For Terpenoid Biosynthesis In Medicago Truncatula, Mandy M. Cox
Inquiry: The University of Arkansas Undergraduate Research Journal
In addition to having numerous applications as food flavorings and pharmaceuticals, terpenoids are an important class of defensive compounds that can accumulate in plants after pathogen infection or injury by insects. Sequences of DNA encoding putative terpene synthases and an oxidosqualene synthase, isolated from insect-damaged Medicago truncatula leaves, were selected from an expressed sequence tag (EST) database. The eDNA clones were used as radiolabeled probes to analyze gene expression in leaves treated with factors known to trigger a defense response in plants. Transcript levels for all of the genes examined increased in response to artificial wounding, insect herbivory, and methyl …
Plantain Sunflower (Helianthus Occidentalis Subsp. Plantagineus) In Arkansas, Daniel L. Marsh, Timothy A. Golden
Plantain Sunflower (Helianthus Occidentalis Subsp. Plantagineus) In Arkansas, Daniel L. Marsh, Timothy A. Golden
Journal of the Arkansas Academy of Science
No abstract provided.
First Record Of Leptodora Kindti In Dardanelle Reservoir And Status Of Other Recent Additions To Dardanelle Fauna, John D. Rickett, Robert L. Watson
First Record Of Leptodora Kindti In Dardanelle Reservoir And Status Of Other Recent Additions To Dardanelle Fauna, John D. Rickett, Robert L. Watson
Journal of the Arkansas Academy of Science
No abstract provided.
Vegetation Of Maple-Leaved Oak Sites On Sugarloaf And Magazine Mountains, Arkansas, David W. Rouw, George P. Johnson
Vegetation Of Maple-Leaved Oak Sites On Sugarloaf And Magazine Mountains, Arkansas, David W. Rouw, George P. Johnson
Journal of the Arkansas Academy of Science
We conducted an analysis of the vegetation of the maple-leaved oak sites on Sugarloaf and Magazine Mountains, Arkansas, during September and October of 1993. The woody vegetation was sampled using the point-quarter method; on Sugarloaf Mountain five transects were sampled (950 m) and on Magazine Mountain four transects were sampled (710 m). Soil samples from each site were collected and analyzed for 15 factors. In total 27 species were recorded and measured for both sites, 18 for Sugarloaf and 19 for Magazine. The Sugarloaf site can be described as a Quercus-Juniperus community and the Magazine site can be described as …
Bryophyte And Pteridophyte Distribution Records Of Southern Arkansas, James R. Bray, Greg A. Whitehead, Daniel L. Marsh, Dennis W. Mcmasters
Bryophyte And Pteridophyte Distribution Records Of Southern Arkansas, James R. Bray, Greg A. Whitehead, Daniel L. Marsh, Dennis W. Mcmasters
Journal of the Arkansas Academy of Science
No abstract provided.
Sex Ratio And Success, An Assessment Of Lindera Melissifolia In Arkansas, Robert D. Wright
Sex Ratio And Success, An Assessment Of Lindera Melissifolia In Arkansas, Robert D. Wright
Journal of the Arkansas Academy of Science
Lindera melissifolia pondberry, is a federally endangered dioecious shrub found in Arkansas and four other southeastern states. Although by far the greatest area exists in Arkansas, it is broken into numerous small single-sex clones concentrated in two locations. Several stands have been lost during the 1980's according to records of the Arkansas Natural Heritage Commission. Even casual observation reveals that there are more males than females. This suggests dependence on vegetative reproduction, with possible bias against females. This paper reports on work investigating this suggestion. It was found that a 7:1 bias in area covered favors males. Poor survival of …
Additional Occurrences Of The Bog Clubmosses In Southern Arkansas, James R. Bray, Daniel L. Marsh
Additional Occurrences Of The Bog Clubmosses In Southern Arkansas, James R. Bray, Daniel L. Marsh
Journal of the Arkansas Academy of Science
No abstract provided.
Effect Of Light, Nitrogen, And Water Management On Rice (Oryza Sativa) Tolerance To Fenoxaprop, Roy J. Smith Jr., Aurora M. Baltazar, Paolo Nastasi
Effect Of Light, Nitrogen, And Water Management On Rice (Oryza Sativa) Tolerance To Fenoxaprop, Roy J. Smith Jr., Aurora M. Baltazar, Paolo Nastasi
Journal of the Arkansas Academy of Science
The effect of light intensity, nitrogen (N), and water management on rice (Oryza sativa cv. 'Newbonnet' and 'Lemont') tolerance to fenoxaprop {(+)-2-[4[(6-chloro-2-benzoxazolyl)oxy]phenoxy]propanoic acid} was determined in two field studies at the Rice Research and Extension Center, Stuttgart, AR, in 1988 and 1989. In one study, 'Newbonnet' rice was treated with 0.22 kgai ha-1fenoxaprop at 0, 1, 3, 5, 7, 10, 14, and 28 days after N application and flooding. Moderate to severe foliar chlorosis, stunting, and stand and yield reductions occurred when fenoxaprop was applied within 7 days after N application and flooding. None to slight injury or yield reduction …
Occurrence Of The Hybrid Honey Locust (Gleditsia X Texana Sarg.) In Southwest Arkansas, Brian A. Smith, Daniel L. Marsh
Occurrence Of The Hybrid Honey Locust (Gleditsia X Texana Sarg.) In Southwest Arkansas, Brian A. Smith, Daniel L. Marsh
Journal of the Arkansas Academy of Science
No abstract provided.