Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 9 of 9

Full-Text Articles in Life Sciences

Evaluation Of Novel Input Output Traits In Sorghum Through Biotechnology, Tejinder K. Mall Dec 2010

Evaluation Of Novel Input Output Traits In Sorghum Through Biotechnology, Tejinder K. Mall

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Sorghum [Sorghum bicolor (L.) Moench] is the fifth most important cereal crop world-wide as well as an important source of feed, fiber and biofuel. It is a C4 plant and is well adapted to environments subject to high temperature and water limitation. Despite these agronomic qualities, it suffers from limitations of sensitivity to low temperature and the grain has drawbacks in relation to functionality and digestibility. The objectives of this study are: 1. To promote seed germination at low temperature and to enhance the seedling cold tolerance. 2. To enhance the grain digestibility and functionality. In an attempt to …


Detection Of Soybean Seed Protein Qtls Using Selective Genotyping, Piyaporn Phansak Dec 2010

Detection Of Soybean Seed Protein Qtls Using Selective Genotyping, Piyaporn Phansak

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

A quantitative trait locus (QTL) is a statically defined location of a gene governing that trait. QTL identification is the first step towards using marker-assisted selection (MAS) to introgress desirable QTL alleles into elite high-yield cultivars. Hundreds of high protein plant introductions (PIs) exist in the USDA germplasm collection and are a source of high protein alleles. Although 86 protein QTLs are currently listed in SoyBase, many are likely repeat discoveries of the same QTL(s), given the typical +/- 10 cM confidence intervals associated with QTL positions. Six germplasm accessions of maturity groups (MGs) II to IV that exhibited high …


Fusarium Head Blight: Winter Wheat Cultivar Responses And Characterization Of Pathogen Isolates, John Fredy Hernandez Nopsa Nov 2010

Fusarium Head Blight: Winter Wheat Cultivar Responses And Characterization Of Pathogen Isolates, John Fredy Hernandez Nopsa

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Fusarium head blight (FHB) is a destructive disease of wheat (Triticum aestivum L). FHB reduces yield and grain quality and causes accumulation of the mycotoxin deoxynivalenol (DON) in grain. Cultivar resistance is one of the most effective management strategies for FHB. Experiments were conducted to 1) identify winter wheat cultivars with resistance to FHB and DON accumulation, 2) determine the effect of winter wheat cultivar on the relationship between FHB and DON concentration, and 3) identify the major species of Fusarium causing FHB in Nebraska and characterize its isolates. Differences (P ≤ 0.05) were detected among cultivars in FHB …


Identification Of Sources Of Rhizoctonia Root Rot Resistance In Common Bean And Mapping A New Source Of Bean Rust Resistance From The Tertiary Gene Pool Of Common Bean, Pamela A. Peña-Perdomo Nov 2010

Identification Of Sources Of Rhizoctonia Root Rot Resistance In Common Bean And Mapping A New Source Of Bean Rust Resistance From The Tertiary Gene Pool Of Common Bean, Pamela A. Peña-Perdomo

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

An efficient screening method was developed and used to identify bean lines resistant to Rhizoctonia Root Rot caused by Rhizoctonia solani Kuhn. Two sets of 163 and 111 lines previously evaluated for drought tolerance at Mitchell, NE and Isabela, PR were evaluated for Rhizoctonia Root Rot resistance under greenhouse conditions. This root rot data was also correlated with yield under drought stress and non stress conditions. In the first set of lines the rhizoctonia mean score ranged from 1.7 to 3.9; and in the second set the rhizoctonia mean score was between 2.6 and 5.7. There was no significant correlation …


Xenia Effects On Quality Of Maize Female Inbred In Production Of Hybrid Seeds, Leandro Castañeda Aug 2010

Xenia Effects On Quality Of Maize Female Inbred In Production Of Hybrid Seeds, Leandro Castañeda

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

In Maize (Zea maize L.), cost of hybrid seed production is directly related to the yield and quality of seed obtained per hectare of female parent. It is also important to consider the effects that a male parent can exert on the development of hybrid seed in the female parent. This effect is known as xenia. The objectives of this study were to evaluate xenia effects on 1) yield as 80K units, 2) germination of the hybrid seed and 3) susceptibility of the hybrid seed to mechanical damage. One female inbred and four male inbred lines were selected from a …


Genetic Mapping Of Quantitative Trait Loci Associated With Bioenergy Traits, And The Assessment Of Genetic Variability In Sweet Sorghum (Sorghum Bicolor (L.). Moench), Aatshwaelwe Lekgari Lekgari Aug 2010

Genetic Mapping Of Quantitative Trait Loci Associated With Bioenergy Traits, And The Assessment Of Genetic Variability In Sweet Sorghum (Sorghum Bicolor (L.). Moench), Aatshwaelwe Lekgari Lekgari

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Sweet sorghum, a botanical variety of sorghum is a potential source of bioenergy because high sugar levels accumulate in its stalks. The objectives of this study were to explore the global diversity of sweet sorghum germplasm, and map the genomic regions that are associated with bioenergy traits. In assessing diversity, 142 sweet sorghum accessions were evaluated with three marker types (SSR, SRAP, and morphological markers) to determine the degree of relatedness among the accessions. The traits measured (anthesis date [AD], plant height [PH], biomass yield [BY], and moisture content [MC]) were all significantly different (P<0.05) among accessions. Morphological marker clustered the accessions into five groups based on PH, MC and AD. The three traits accounted for 92.5% of the variation. There were four and five groups based on SRAP and SSR data respectively classifying accessions mainly on their origin or breeding history. The observed difference between SSR and SRAP based clusters could be attributed to the difference in marker type. SSRs amplify any region of the genome whereas SRAP amplify the open reading frames and promoter regions. Comparing the three marker-type clusters, the markers complimented each other in grouping accessions and would be valuable in assisting breeders to select appropriate lines for crossing. In evaluating QTLs that are associated with bioenergy traits, 165 recombinant inbred lines (RILs) were planted at four environments in Nebraska. A genetic linkage map constructed spanned a length of 1541.3 cM, and generated 18 linkage groups that aligned to the 10 sorghum chromosomes. Fourteen QTLs (6 for brix, 3 for BY, 2 each for AD and MC, and 1 for PH) were mapped. QTLs for the traits that were significantly correlated, colocalized in two clusters on linkage group Sbi01b. Both parents contributed beneficial alleles for most of traits measured, supporting the transgressive segregation in this population. Additional work is needed on exploiting the usefulness of chromosome 1 in breeding sorghum for bioenergy.


Quantitative Trait Loci For Agronomic And End-Use Quality Performance And The Effect Of Soilborne Wheat Mosaic Virus In A Hard Winter Wheat Population In Nebraska, Nicholas A. Crowley Jul 2010

Quantitative Trait Loci For Agronomic And End-Use Quality Performance And The Effect Of Soilborne Wheat Mosaic Virus In A Hard Winter Wheat Population In Nebraska, Nicholas A. Crowley

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

To better understand agronomic and end-use quality in wheat (Triticum aestivum L.) we developed a population containing 154 F6:8 recombinant inbred lines (RILs) from the cross TAM107-R7/Arlin. The parental lines and RILs were phenotyped at six environments in Nebraska and differed for resistance to Wheat soilborne mosaic virus (WSBMV), morphological, agronomic, and end-use quality traits. Additionally, a 2300 cM genome-wide linkage map was created for quantitative trait loci (QTL) analysis. Based on our results across multiple environments, the best RILs could be used for cultivar improvement. The population and marker data are publicly available for interested researchers for future research. …


Grain Yield And Yield-Related Qtl Validation Using Reciprocal Recombinant Inbred Chromosome Lines In Wheat, Neway C. Mengistu Apr 2010

Grain Yield And Yield-Related Qtl Validation Using Reciprocal Recombinant Inbred Chromosome Lines In Wheat, Neway C. Mengistu

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Grain yield and yield-related traits are the most important economic factors for bread wheat (Triticum aestivum L.) improvement. Grain yield (GYLD) and yield-related quantitative trait loci (QTLs) were previously identified by using a population of recombinant inbred chromosome lines (RICLs) developed from cultivar ‘Cheyenne’ (CNN) and its substitution line CNN(WI3A), where the 3A chromosome of cultivar ‘Wichita’ (WI) was substituted for the CNN chromosome 3A. The objectives of this study were to identify and validate GYLD and yield-related QTLs previously identified in CNN(RICLs-3A) studies by using the mirror population WI(RICLs-3A), where chromosome 3A of CNN and WI were now …


Genetic Diversity Of Wheat Cultivars From Turkey And U.S. Great Plains, Anyamanee Auvuchanon Jan 2010

Genetic Diversity Of Wheat Cultivars From Turkey And U.S. Great Plains, Anyamanee Auvuchanon

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Genetic diversity of wheat cultivars from Turkey and the Great Plains was studied under the hypothesis ‘Turkey’ wheat originated from Turkey and is the original hard red winter wheat landrace in the Great Plains. Wheat cultivars in Turkey and the Great Plains were selected for adaptation in two countries which were similar in climate. Twenty-two Turkish and twenty-three Great Plains wheat cultivars were selected for this study using SSR markers, agronomic, and end-use quality traits data. Wheat cultivars were clustered into five groups based on SSR markers and the clustering largely followed their countries of origin and pedigree. Modern Great …