Soil Science Commons^™

Modeling Spatial Distributions Of Tidal Marsh Blue Carbon Using Morphometric Parameters From Lidar, Bonnie Turek

Masters Theses

Tidal marshes serve as important “blue carbon” ecosystems that accrete large amounts of carbon with limited area. While much attention has been paid to the spatial variability of sedimentation within salt marshes, less work has been done to characterize spatial variability in marsh carbon density. Driven by tidal inundation, surface topography, and sediment supply, soil properties in marshes vary spatially with several parameters, including marsh platform elevation and proximity to the marsh edge and tidal creek network. We used lidar to extract these morphometric parameters from tidal marshes to map soil organic carbon (SOC) at the meter scale. Fixed volume …

Soil Properties Associated With Land Management Practices In Western Kentucky, Ava Isaacs, Gracey Moffitt

Scholars Week

Soil Properties Associated with Land Management Practices in Western Kentucky

1. A. Isaacs, G. Moffitt, W. Sides, and Corey Hale

Mentor: Dr. I.P. Handayani

Hutson School of Agriculture, Murray State University, Kentucky, USA

Abstract

One of the most important factors regarding soil and plant health is nutrient availability and fertility. Of these two factors that were mentioned available potassium is a key component. With that being said we decided that it would be beneficial to see how potassium can be traced within the soil in various locations after fertilizer is applied. There were two parts to this experiment. Part one was …

Spatial Variations Of Soil Properties Under Corn Field In Kentucky, Usa, Sai Neela Kesumala, Dr. Iin Handayani

Scholars Week

Precision farming involves modifying the rate of fertilizer, herbicides, and irrigation in response to crops’ requirements. For precision management, a better understanding of spatial variability of soil properties within a field is important. To fully utilize cultivation and site-specific crop production technology, it is crucial to understand the dynamics of soil properties spatially. Several factors, such as unequal fertilizer and manure application, erosion, tillage, and inborn variances formed during soil development, can contribute to spatial variation. The purpose of this study was to evaluate the spatial distribution of selected soil properties in the four border rows, the plot's center, and …

Gene Discovery And Molecular Dissection Of Lignin Biosynthesis In Perennial Ryegrass (Lolium Perenne), A. Lidgett, M. Emmerling, R. Heath, R. Mcinnes, D. Lynch, A. Bartkowski, K. Fulgueras, T. Sawbridge, E. K. Ong, K. F. Smith, A. Mouradov, G. C. Spangenberg

International Grassland Congress Proceedings

Lignification of plant cell walls has been identified as a major factor limiting forage digestibility. It limits the amount of digestible energy available to livestock, resulting in an incomplete utilisation of cellulose and hemicellulose by ruminant animals. Modification of the lignin profile of ryegrasses (Lolium spp.) and fescues (Festuca spp.) is undertaken through modulating the expression of genes encoding enzymes involved in the biosynthesis of monolignols.

Identification Of Putative AtTt2 R2r3-Myb Transcription Factor Orthologues In Tanniferous Tissues Of L. Corniculatus Var. Japonicus Cv Gifu, D. N. Bryant, P. Bailey, P. Morris, Mark P. Robbins, C. Martin, T. Wang

International Grassland Congress Proceedings

R2R3-MYB plant transcription factors are sequence–specific DNA-binding proteins, which regulate the expression of specific gene(s) following the R2R3 DNA-binding domain interacting with the corresponding promoter sequence(s). The biosynthetic pathway leading to the production of anthocyanins has been demonstrated to be under MYB transcriptional regulatory control (Cone et al., 1986), while the accumulation of proanthocyanidins (PAs) in Arabidopsis seed coats is determined by the R2R3-MYB AtTT2 (Nesi et al., 2001). Using an informatics approach, partial sequences of putative AtTT2 orthologues have been identified and cloned from the forage legume Lotus corniculatus var. japonicus cv Gifu.

Foliar Expression Of Candidate Genes Involved In Condensed Tannin Biosynthesis In White Clover (Trifolium Repens), Stephen N. Panter, J. Simmonds, A. Winkworth, A. Mouradov, G. C. Spangenberg

International Grassland Congress Proceedings

Bloat disease in cattle and sheep is caused by the rapid microbial degradation of protein-rich fodder in the rumen. This leads to the production of protein foams that trap gases, causing bloat, a condition that is often fatal to livestock and costly to farmers. Condensed tannins (CTs) are phenolic polymers produced by the phenylpropanoid pathway of plants (Figure 1). CTs bind to proteins under acidic to neutral conditions, such as those present in the rumen, slowing their breakdown. A diet with a CT content of between 2% and 4% by dry weight, which is provided by some pasture legumes (e.g. …

Discovery, Isolation And Characterisation Of Promoters In White Clover (Trifolium Repens), C. M. Labandera, Y. H. Lin, E. Ludlow, M. Emmerling, U. John, P. W. Sale, C. Pallaghy, G. C. Spangenberg

International Grassland Congress Proceedings

The availability of a suite of promoters with a range of spatial, temporal and inducible expression patterns is of significant importance to control targeted expression of genes for molecular breeding in forage species. A range of resources and tools have been developed for promoter isolation and characterisation in white clover (Trifolium repens L.), including a comprehensive BAC library and a 15K unigene microarray.

Novel Genotypes Of The Subtropical Grass Eragrostis Curvula For The Analysis Of Apomixis (Diplospory), S. Cardone, P. Polci, J. P. Selva, M. Mecchia, S. C. Pessino, P. Voigt, G. C. Spangenberg, V. Echenique

International Grassland Congress Proceedings

Eragrostis curvula (Schrad.) Nees is a variable grass native to Southern Africa. Its several forms, known as lovegrasses, were introduced to Australia, USA and Argentina as forage perennial grasses. Apomixis is a common trait in the genus Eragrostis, with diplospory being the most frequent type. Sexual reproduction also occurs in Eragrostis, although not frequently. Since most tetraploid Eragrostis lines are apomictic, the generation of a sexual tetraploid strain is a requirement for linkage analysis of the gene(s) governing the apomictic character. Furthermore, isogenic lines of the same ploidy, reproducing alternatively by sexuality or apomixes, represent an ideal system …

Isolation And Characterisation Of Genes Encoding Malate Synthesis And Transport Determinants In The Aluminum-Tolerant Australian Weeping-Grass (Microlaena Stipoides), R. M. Polotnianka, E. Ribarev, L. Mackin, K. A. Sivakumaran, G. D. Nugent, U. P. John, G. C. Spangenberg

International Grassland Congress Proceedings

Acid soils cover some 40% of the Earth’s arable land where they represent a major limitation to plant production. Plant growth on acid soils is primarily limited due to aluminium (Al) solubilized by acidity into toxic Al³⁺ cations which will inhibit root growth resulting in poor uptake of water and nutrients. Many important pasture species lack sufficient Al tolerance within their germplasm to allow effective breeding for this character.

Development And Use Of A Tool For Automated Alignments Of Genes In The Rice Bac's Genbank Card Against Other Species, P. Barre, G. Darrieutort, J. Auzanneau, B. Julier

International Grassland Congress Proceedings

In many cases, the analysis of the genetic bases of any trait requires molecular markers and if possible co-dominant PCR-based ones. In perennial fodder species, the number of publicly available markers (microsatellites and Sequence Tagged Site (STS)) is limited. Our goal is to use sequences from model grass species, i.e. rice, wheat, maize, barley, in L. perenne in order to develop STS markers in interesting regions such as under a QTL (Quantitative Trait Loci) or around a candidate gene,. As the genome sequence of rice is now available, the objective was to use the sequences of genes included in the …

Screening Of Perennial Grasses And A Mutant Maize Collection By Fourier-Transformed Infrared (Ftir) Spectroscopy For Improved Biofuel Traits, S. C. Thain, P. Morris, S. Hawkins, C. Morris, I. S. Donnison

International Grassland Congress Proceedings

Currently the potential of biomass crops, including grasses, is limited because most species have not been bred for this purpose. However traits such as lignification, phenolic cross-linking and carbohydrate accessibility, which are also important for nutritive quality in forage grasses, can affect potential biofuel quality in applications such as combustion, fast-pyrolysis or fermentation. A collection of Lolium and Festuca species known to exhibit a range of lignin, cell wall phenolic and carbohydrate concentrations have been used to test optimum characteristics for biofuel processing. This collection formed a “calibration” set for subsequent high through-put FTIR chemical screening of additional plant lines: …

Application Of Molecular Markers Derived From Medicago Truncatula In White Clover (Trifolium Repens L.), C. Jones, M. T. Abberton

International Grassland Congress Proceedings

White clover is the major forage legume of temperate areas. Genome maps have been produced recently (Jones et al., 2003; Barrett et al., 2004) and the location of QTL for important agricultural traits reported (Abberton et al., 2004). White clover is closely related to the model legume Medicago truncatula and there is likely to be considerable benefit in applying genomic resources from model to crop. However, the extent of synteny between the species must be established. Here we present preliminary results detailing progress towards this goal.

A Proposal For An International Transcriptome Initiative For Forage And Turf: Microarray Tools For Expression Profiling In Ryegrass, Clover And Grass Endophytes, T. Webster, N. Nguyen, C. Rhodes, S. A. Felitti, R. Chapman, D. Edwards, G. C. Spangenberg

International Grassland Congress Proceedings

Knowledge of the expression pattern of genes provides a valuable insight into gene function and role in determining the observed heritable phenotype. High–density cDNA and oligonucleotide microarrays represent powerful tools for transcriptome analysis to gain an understanding of gene expression patterns for thousands of genes. Internationally coordinated efforts in transcriptome analyses and sharing of microarray resources will benefit the advancement of our understanding of gene function in forage and turf species.

Screening Genes For Association With Loci For Nitrogen-Use Efficiency In Perennial Ryegrass By PyrosequencingTm, O. Dolstra, D. Dees, J. -D. Driesprong, E. N. Van Loo

International Grassland Congress Proceedings

The application of marker-assisted selection to improve quantitative traits in perennial ryegrass (Lolium perenne) is cumbersome. It requires a priori knowledge on the association of markers and genes. The knowledge on the chromosomal location of major genes for quantitative traits as well as on gene sequences is rapidly growing. However, determination of the genetic constitution of parents prior to their use in breeding still is impractical. More realistic is to collect association data along with the testing activities needed for breeding new varieties. This study uses changes in allele frequency due to selection as a criterion for gene-trait …

Gene-Associated Single Nucleotide Polymorphism (Snp) Discovery In Perennial Ryegrass (Lolium Perenne L.), J. W. Forster, N. O. I. Cogan, A. C. Vecchies, R. C. Ponting, M. C. Drayton, J. George, J. L. Dumsday, G. C. Spangenberg, K. F. Smith

International Grassland Congress Proceedings

Perennial ryegrass (Lolium perenne L.) is the most important grass species for temperate pasture systems world-wide. Varietal improvement programs for this obligate outbreeding species are based on polycrossing of multiple parents to produce heterogeneous synthetic populations. The complexity of breeding systems creates challenges and opportunities for molecular marker technology development and implementation. Previous research has led to: the generation of a comprehensive suite of simple sequence repeat (SSR) markers, reference genetic map construction, comparative genetic studies, QTL identification, and population structure analysis. Emphasis has now shifted from the use of anonymous genetic markers linked to trait-specific genes to the …

Isolation Of Candidate Genes Involved In Cold Temperatures Response In Festuca Pratensis Huds., Using Suppression Subtractive Hybridisation And Microarray Approaches, H. Rudi, V. Alm, L. Opseth, A. Larsen, O. A. Rognli

International Grassland Congress Proceedings

The objective of this work was to isolate candidate genes which are differentially expressed following cold-acclimation and develop SNPs to test for associations between candidate genes and frost tolerance. The ability to develop sufficient levels of tolerance against freezing temperatures through cold-acclimation (hardening) is crucial for survival of grasses and winter cereals in temperate climate. Meadow fescue (Festauca pratensis Huds.) is one of the most important forage grass species in Northern Europe. The preference of Festuca instead of Lolium in Norway is due to its superior combination of winter hardiness and forage quality.

Positive Effect Of Increased Aflp Diversity Among Parental Plants On Yield Of Polycross Progenies In Perennial Ryegrass (Lolium Perenne L.), R. Kölliker, B. Boller, F. Widmer

International Grassland Congress Proceedings

In outbreeding forage crops such as perennial ryegrass (Lolium perenne L.), genetic diversity among parental plants may greatly influence the success of a cultivar through mechanisms such as heterosis and inbreeding depression. The aim of this study was to evaluate the use of amplified fragment length polymorphism (AFLP) markers to select polycross parents with contrasting levels of genetic diversity and to analyse genetic diversity and agronomic performance of first and second generation synthetic progenies (Syn1, Syn2).

Ryegrass Astra: A Web-Based Resource For Lolium Est Analysis, G. C. Spangenberg, T. Sawbridge, E. K. Ong, C. G. Love, T. A. Erwin, E. G. Logan, D. Edwards

International Grassland Congress Proceedings

Perennial ryegrass (Lolium perenne L.) is a major grass species of temperate pastoral agriculture.

Genomic Constitution Of Festulolium Varieties, D. Kopecky, V. Cernoch, R. Capka, J. Dolezel

International Grassland Congress Proceedings

Hybrids between species of ryegrass (Lolium) and fescue (Festuca) combine useful agronomical characteristics such as rapid establishment from seed and fodder quality from ryegrass and tolerance against abiotic and biotic stressses from fescue. The superior potential of hybrids has stimulated breeding programs generating so called Festulolium varieties. While the varieties have been evaluated extensively for their agronomic characteristics, little information is publicly available on their genomic constitution. The aim of our study was to analyse genomic constitution of a representative set of commercially available European Festulolium cultivars. To do this, we have employed genomic in situ …

Genetic Changes Over Breeding Generations Of Festulolium, M. Ghesquière, P. Barre, L. Barrot

International Grassland Congress Proceedings

Festulolium hybrids are a valuable breeding source for tolerance to abiotic stress and to make grass more persistent under drought and in cold environments. In 2004, the EU Commission enlarged the definition of Festulolium which may now include all hybrids between Lolium sp. and Festuca sp. and not only those between L. multiflorum and F. pratensis. We here report allele frequencies at two unlinked PCR-based marker loci in populations derived from tetraploid (2n=4x=28) L. multiflorum x F. glaucescens hybrids where breeding history enables us to test the effects of selection vs that of genetic drift.