The integration of quantitative trait locus mapping and transcriptome studies reveals candidate genes for water stress response in St. Augustinegrass.

Background: Drought resistance is an increasingly important trait for many plants-including St. Augustinegrass, a major warm-season turfgrass-as more municipalities impose restrictions on frequency and amount of irrigation. Breeding efforts have focused on breeding for drought resistance, and several drought-related quantitative trait loci (QTL) have been identified for St.

Assessing Pesticide Residue Levels in Sweetpotato Roots and Slips Treated with Fungicides for Management of Southern Blight and Circular Spot Disease Caused by .

Since 1971, North Carolina (NC) has been the leading sweetpotato-producing state in the United States and is now producing more than half of the nation's annual output. Because of the high demand for U.S.

Scaling of soil organic carbon in space and time in the Southern Coastal Plain, USA.

Soil organic carbon (SOC) is a dynamic soil property (DSP) that represents the largest portion of terrestrial carbon. Its relevance to carbon sequestration and the potential effects of land use on SOC storage, make it imperative to map across both space and time. Most regional-scale studies mapping SOC give static estimates and train different models for different periods with varying accuracies.

Realistic Physiological Options to Increase Grain Legume Yield under Drought.

Increasing yield resiliency under water deficits remains a high priority for crop improvement. In considering the yield benefit of a plant trait modification, two facts are often overlooked: (1) the total amount of water available to a crop through a growing season ultimately constrains growth and yield cannot exceed what is possible with the limited amount of available water, and (2) soil water content always changes over time, so plant response needs to be considered within a temporally dynamic context of day-to-day variation in soil water status. Many previous evaluations of drought traits have implicitly considered water deficit from a "static" perspective, but while the static approach of stable water deficit treatments is experimentally congruous, the results are not realistic representations of real-world drought conditions, where soil water levels are always changing.

Characterization of a Host-Specific Toxic Activity Produced by , Causal Agent of Target Leaf Spot of Sorghum.

Target leaf spot (TLS) of sorghum, caused by the necrotrophic fungus , can cause severe yield loss in many parts of the world. We grew in liquid culture and observed that the resulting culture filtrate (CF) was differentially toxic when infiltrated into the leaves of a population of 288 diverse sorghum lines. In this population, we found a significant correlation between high CF sensitivity and susceptibility to TLS.

Why soil testing is not enough: A mixed methods study of farmer nutrient management decision-making among U.S. producers.

Understanding farmers' nutrient management decision-making is critical to minimizing nutrient loss to water resources. This research examines farmer decision-making in the United States surrounding nutrients (primarily nitrogen and phosphorus) and water quality among 105 farmers in Missouri, North Carolina, and Ohio. Data were collected between 2015 and 2016 using a mixed-methods approach of in-person farmer interviews and accompanying quantitative surveys with demographic and Likert ranking questions.

Bioaccumulation and Heavy Metal Contamination in Fish Species of the Dhaleswari River of Bangladesh and Related Human Health Implications.

The release of a large quantity of heavy metals into the Dhaleswari River from the tannery, dyeing, and other industrial setups and their subsequent transfer to food chains through fish consumption have been an alarming issue in Bangladesh. To study the pollution level, a total of seven fish species, namely Heteropneustes fossillis, Channa punctata, Nandus nandus, Chanda nama, Anabas testudineus, Mystus gulio, and Colisa fasciata, were collected in winter from the Dhaleswari River and the total concentrations of Cr, Pb, Ni, and Zn in head and body tissues were analyzed separately. The concentrations of Cr, Pb, and Zn were found 300, 20, and 10 times higher, respectively, than the guideline value of the Food and Agriculture Organization (FAO)/World Health Organization (WHO), indicating possible health risks to humans.

Nitrogen leaching and Tifway bermudagrass response to simultaneous nutrient and pre-emergence herbicide applications.

Pre-emergence (PRE) herbicides are commonly applied simultaneously with fertilizers to turfgrass; however, the influence of PRE herbicides on nitrogen (N) uptake and leaching from turfgrass remains unclear. The hypothesis of this study was that PRE herbicides applied simultaneously with N fertilizers increase N leaching from Tifway 419 bermudagrass [Cynodon dactylon (L.) Pers.

Immobilization of lead by amendments in a mine-waste impacted soil: Assessing Pb retention with desorption kinetic, sequential extraction and XANES spectroscopy.

Chemical stabilization is an in-situ remediation that uses amendments to reduce contaminant availability in polluted soils. Rates of phosphate, lime, biochar, and biosolids were evaluated as affecting Pb speciation and mobility in soil samples of a mining area located in Vazante, state of Minas Gerais, Brazil. Chemical and mineralogical characterization, desorption kinetics, sequential extraction, leaching evaluation in columns and speciation using X-ray absorption near edge structure were performed.

Evaluation and genome-wide association study of resistance to bacterial blight race 18 in U.S. Upland cotton germplasm.

Bacterial blight (BB), caused by Xanthomonas citri pv. malvacearum (Xcm), is a destructive disease to cotton production in many countries. In the U.

The importance of dominance and genotype-by-environment interactions on grain yield variation in a large-scale public cooperative maize experiment.

High-dimensional and high-throughput genomic, field performance, and environmental data are becoming increasingly available to crop breeding programs, and their integration can facilitate genomic prediction within and across environments and provide insights into the genetic architecture of complex traits and the nature of genotype-by-environment interactions. To partition trait variation into additive and dominance (main effect) genetic and corresponding genetic-by-environment variances, and to identify specific environmental factors that influence genotype-by-environment interactions, we curated and analyzed genotypic and phenotypic data on 1918 maize (Zea mays L.) hybrids and environmental data from 65 testing environments.

Abscisic Acid and Sulfate Offer a Possible Explanation for Differences in Physiological Drought Response of Two Maize Near-Isolines.

The hypothesis was tested that differences in response to water-deficits between low osmotic potential (LOP) and high osmotic potential (HOP) maize ( L.) near-isolines were associated with differences in transpiration rate sensitivity to abscisic acid (ABA) and/or sulfate. In a series of four experiments, decreases in transpiration rate (DTR) of whole plants and fully expanded leaves were measured in response to treatments of 1.

Genome-wide association analysis of the strength of the MAMP-elicited defense response and resistance to target leaf spot in sorghum.

Plants have the capacity to respond to conserved molecular features known as microbe-associated molecular patterns (MAMPs). The goal of this work was to assess variation in the MAMP response in sorghum, to map loci associated with this variation, and to investigate possible connections with variation in quantitative disease resistance. Using an assay that measures the production of reactive oxygen species, we assessed variation in the MAMP response in a sorghum association mapping population known as the sorghum conversion population (SCP).

Soil surfactants influence fungicide movement in United States Golf Association putting green soil.

The management of root and crown diseases of turfgrasses is challenging. To manage these diseases, golf course superintendents and other turfgrass managers often spray fungicides at a high carrier volume and irrigate after application to move fungicides into the root zone. Furthermore, previous research has demonstrated that soil surfactants can increase fungicide movement and distribution in soil.

Sleep tight and wake-up early: nocturnal transpiration traits to increase wheat drought tolerance in a Mediterranean environment.

In wheat, night-time transpiration rate (TRN) could amount to 14-55% of daytime transpiration rate (TR), depending on the cultivar and environment. Recent evidence suggests that TRN is much less responsive to soil drying than daytime TR, and that such 'wasteful' water losses would increase the impact of drought on yields. In contrast, other evidence indicates that pre-dawn, circadian increases in TRN may enable enhanced radiation use efficiency, resulting in increased productivity under water deficit.

Transcriptome-Based Analysis of Tomato Genotypes Resistant to Bacterial Spot ( Race T4.

Bacterial spot (BS) is one of the most devastating foliar bacterial diseases of tomato and is caused by multiple species of . We performed the RNA sequencing (RNA-Seq) analysis of three tomato lines with different levels of resistance to race T4 to study the differentially expressed genes (DEGs) and transcript-based sequence variations. Analysis between inoculated and control samples revealed that resistant genotype accession PI 270443 had more DEGs (834), followed by susceptible genotype tomato ( L) breeding line NC 714 (373), and intermediate genotype tomato breeding line NC 1CELBR (154).

The effects of compost incorporation on soil physical properties in urban soils - A concise review.

Incorporation of compost into soil can significantly alter soil physical properties, nutrient dynamics, and vegetation establishment. Strategic compost application to disturbed, degraded urban soil may provide benefits to soil properties. This review compared twenty-five peer-reviewed studies that evaluated changes in soil bulk density, infiltration rate, hydraulic conductivity, and water retention where compost was incorporated into urban soils.

Genome-wide association analysis for maize stem Cell Wall-bound Hydroxycinnamates.

Background: The structural reinforcement of cell walls by hydroxycinnamates has a significant role in defense against pests and pathogens, but it also interferes with forage digestibility and biofuel production. Elucidation of maize genetic variations that contribute to variation for stem hydroxycinnamate content could simplify breeding for cell wall strengthening by using markers linked to the most favorable genetic variants in marker-assisted selection or genomic selection approaches​.

Results: A genome-wide association study was conducted using a subset of 282 inbred lines from a maize diversity panel to identify single nucleotide polymorphisms (SNPs) associated with stem cell wall hydroxycinnamate content.

A genome-wide association study uncovers consistent quantitative trait loci for resistance to Verticillium wilt and Fusarium wilt race 4 in the US Upland cotton.

A high-resolution GWAS detected consistent QTL for resistance to Verticillium wilt and Fusarium wilt race 4 in 376 U.S. Upland cotton accessions based on six independent replicated greenhouse tests.

Biomass of the Cyanobacterium Lyngbya wollei Alters Copper Algaecide Exposure and Risks to a Non-target Organism.

Nuisance algal infestations are increasing globally in distribution and frequency. Copper-based algaecides are routinely applied to control these infestations, though there is an ever-present concern of risks to non-target species. This research evaluated risks associated with a commonly applied chelated copper algaecide (Captain® XTR; SePRO Corporation) to a sentinel non-target species (Daphnia magna) and further assessed alteration of the exposure and toxicity when a nuisance mat-forming cyanobacterium, Lyngbya wollei, was present in exposures.

Mapping of resistance to corn borers in a MAGIC population of maize.

Background: Corn borers constitute an important pest of maize around the world; in particular Sesamia nonagrioides Lefèbvre, named Mediterranean corn borer (MCB), causes important losses in Southern Europe. Methods of selection can be combined with transgenic approaches to increase the efficiency and durability of the resistance to corn borers. Previous studies of the genetic factors involved in resistance to MCB have been carried out using bi-parental populations that have low resolution or using association inbred panels that have a low power to detect rare alleles.

Increasing Photosynthesis: Unlikely Solution For World Food Problem.

Increasing the photosynthesis rate of plants has been recently revitalized as an approach for increasing grain crop yields and solving world food crises. The idea that photosynthesis is the key to increasing grain crop yields is not new. Considerable research in the 1970s and 1980s showed that carbon input was not limiting for crop growth and yield.

Sorption of copper and phosphate to diverse biogenic iron (oxyhydr)oxide deposits.

Iron (Fe) transformations partially control the biogeochemical cycling of biologically and environmentally important elements, such as carbon (C), nitrogen (N), phosphorus (P), and trace metals. In marine and freshwater environments, iron oxidizing bacteria commonly promote the oxidation of ferrous iron (Fe(II)) at circumneutral oxic-anoxic interfaces, resulting in the formation of mineral-organic composites known as biogenic Fe(III) (oxyhydr)oxides (BIOS). Previous studies have examined the microbial ecology, composition, morphology, and sorption reactivity of BIOS.

High density genetic maps of St. Augustinegrass and applications to comparative genomic analysis and QTL mapping for turf quality traits.

Background: St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze] is a warm-season, perennial turfgrass species well adapted for home lawns and commercial landscapes with economic and ecological value.

Plant Genetics: Two Steps on the Path to Maize Adaptation.

Two distinct variations in the promoter of a key flowering time gene were selected during the spread of maize from its tropical origin to northern North America.