Plant Breeding and Genetics Commons^™

Orm Expression Alters Sphingolipid Homeostasis And Differentially Affects Ceramide Synthase Activity, Athen N. Kimberlin, Gongshe Han, Kyle D. Luttgeharm, Ming Chen, Rebecca E. Cahoon, Julie M. Stone, Jennifer E. Markham, Teresa M. Dunn, Edgar B. Cahoon

Center for Plant Science Innovation: Faculty Publications

Sphingolipid synthesis is tightly regulated in eukaryotes. This regulation in plants ensures sufficient sphingolipids to support growth while limiting the accumulation of sphingolipid metabolites that induce programmed cell death. Serine palmitoyltransferase (SPT) catalyzes the first step in sphingolipid biosynthesis and is considered the primary sphingolipid homeostatic regulatory point. In this report, Arabidopsis (Arabidopsis thaliana) putative SPT regulatory proteins, orosomucoidlike proteins AtORM1 and AtORM2, were found to interact physically with Arabidopsis SPT and to suppress SPT activity when coexpressed with Arabidopsis SPT subunits long-chain base1 (LCB1) and LCB2 and the small subunit of SPT in a yeast ( …

Influence Of Source Credibility On Consumer Acceptance Of Genetically Modified Foods In China, Mingyang Zhang, Chao Chen, Wuyang Hu, Lijun Chen, Jintao Zhan

Agricultural Economics Faculty Publications

This paper examines the reasoning mechanism behind the consumer acceptance of genetically modified foods (GMFs) in China, and investigates influence of source credibility on consumer acceptance of GMFs. Based on the original Persuasion Model—which was developed by Carl Hovland, an American psychologist and pioneer in the study of communication and its effect on attitudes and beliefs—we conducted a survey using multistage sampling from 1167 urban residents, which were proportionally selected from six cities in three economic regions (south, central, and north) in the Jiangsu province through face to face interviews. Mixed-process regression that could correct endogeneity and ordered probit model …

Transcriptome Response Of Cassava Leaves Under Natural Shade, Zehong Ding, Yang Zhang, Yi Xiao, Fangfang Liu, Minghui Wang, Xinguang Zhu, Peng Liu, Qi Sun, Wenquan Wang, Ming Peng, Tom Brutnell, Pinghua Li

Center for Plant Science Innovation: Faculty Publications

Cassava is an important staple crop in tropical and sub-tropical areas. As a common farming practice, cassava is usually cultivated intercropping with other crops and subjected to various degrees of shading, which causes reduced productivity. Herein, a comparative transcriptomic analysis was performed on a series of developmental cassava leaves under both full sunlight and natural shade conditions. Gene expression profiles of these two conditions exhibited similar developmental transitions, e.g. genes related to cell wall and basic cellular metabolism were highly expressed in immature leaves, genes involved in lipid metabolism and tetrapyrrole synthesis were highly expressed during the transition stages, and …

Genetic Basis Of Biosynthesis And Cytotoxic Activity Of Medicago Truncatula Triterpene Saponins, Brynn Kathleen Lawrence

Graduate Theses and Dissertations

Saponins are a large family of specialized metabolites produced in many plants. They can have negative effects on a number of plant pests and are thought to play a role in plant defense. With current and possible future uses in industry and agriculture, saponins have also been shown to be hypocholesterolemic, hypoglycemic, immunostimulatory, antioxidative, anti-inflammatory, and cytotoxic. In spite of their usefulness, our understanding of the genetic basis for saponin biosynthesis is still incomplete. We generated recombinant populations with parents from genetically distinct accessions of Medicago truncatula, with either high or low accumulation and varying profiles of saponins. Primers for …

Phenotypic And Gene Expression Analysis Of Diverse Rice Genotypes In Response To Drought, Miranti Rahmaningsih

Graduate Theses and Dissertations

Drought is one of the most limiting factors for rice (Oryza sativa L.) growth and development with vegetative and reproductive stages the most sensitive and distinct phases. During the vegetative stage, drought can cause reduction in growth and biomass accumulation. Moreover, water stress at reproductive stage can reduce yield significantly. Plants are protected against drought by three different mechanisms: drought avoidance, drought tolerance, and drought escape. An integrated approach combining physiology, breeding, and genomics could be an effective way to characterize and mitigate this problem. The objectives of this research were to (1) screen a diverse set of rice genotypes …

Comparative Evolutionary Analysis Of Organellar Genomic Diversity In Green Plants, Weishu Fan

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

The mitochondrial genome (mitogenome) and plastid genome (plastome) of plants vary immensely in genome size and gene content. They have also developed several eccentric features, such as the preference for horizontal gene transfer of mitochondrial genes, the reduction of the plastome in non-photosynthetic plants, and variable amounts of RNA editing affecting both genomes. Different organismal lifestyles can partially account for the highly diverse organellar genomes across the tree of green plants. For example, endosymbiotic and parasitic lifestyles can dramatically affect the genomic architectures of plant mitochondria and plastids. In this study, the organellar genomes of several green plants with atypical …

Reducing Pollen Dispersal Using Forest Windbreaks, Carol Auer, Thomas Meyer, Vernie Sagun

Plant Science Articles

The adoption of genetically engineered (GE) crops has created a demand for practical methods to mitigate pollen dispersal and gene flow. The goal of this project was to measure the ability of a narrow forest windbreak to reduce downwind pollen fluxes from switchgrass (Panicum virgatum L.), a North American grass and model biofuels feedstock. Switchgrass fields were established in two identical plots where one had a forest windbreak and the other was in an open (control) site. Switchgrass reproduction, pollen dispersal, wind speed, and wind direction were measured over two years. Daily release of switchgrass pollen peaked at 11:00-13:30 …

A Heavy Metal P-Type Atpase Oshma4 Prevents Copper Accumulation In Rice Grain, Xin-Yuan Huang, Fenglin Deng, Naoki Yamaji, Shannon R.M. Pinson, Miho Fujii-Kashino, John Danku, Alex Douglas, Mary Lou Guerinot, David Salt, Jian Feng Ma

Dartmouth Scholarship

Rice is a major source of calories and mineral nutrients for over half the world's human population. However, little is known in rice about the genetic basis of variation in accumulation of copper (Cu), an essential but potentially toxic nutrient. Here we identify OsHMA4 as the likely causal gene of a quantitative trait locus controlling Cu accumulation in rice grain. We provide evidence that OsHMA4 functions to sequester Cu into root vacuoles, limiting Cu accumulation in the grain. The difference in grain Cu accumulation is most likely attributed to a single amino acid substitution that leads to different OsHMA4 transport …

Distribution Of Genomic Variation In The Usda Soybean Germplasm Collection And Relationship With Phenotypic Variation, Nonoy Batiller Bandillo

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

The USDA Soybean Germplasm Collection harbors a large stock of genetic diversity with potential to accelerate soybean cultivar development. The extent and nature of favorable alleles contained in the collection are not well known nor is the distribution of genetic variation and how it relates to phenotypic variation. The genotyping of the entire USDA Soybean Germplasm Collection marked the beginning of a systematic exploration of genetic diversity for genetic research and breeding. In this research, we conducted the first comprehensive analysis of population structure on the collection of ~14,400 soybean accessions [Glycine max (L.) Merr. and G. soja Siebold …

Rna-Seq Based Analysis Of Population Structure Within The Maize Inbred B73, Zhikai Liang, James C. Schnable

Center for Plant Science Innovation: Faculty Publications

Recent reports have shown than many identically named genetic lines used in research around the world actually contain large amounts of uncharacterized genetic variation as a result of cross contamination of stocks, unintentional crossing, residual heterozygosity within original stocks, or de novo mutation. 27 public, large scale, RNA-seq datasets from 20 independent research groups around the world were used to assess variation within the maize (Zea mays ssp. mays) inbred B73, a four decade old variety which served as the reference genotype for the original maize genome sequencing project and is widely used in genetic, genomic, and phenotypic research. Several …

Regeneration: An Overlooked Aspect Of Trait-Based Plant Community Assembly Models, Julie Larson, Jennifer L. Funk

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Despite the disproportionate influence that propagule production, dispersal, seed to seedling recruitment, and vegetative reproduction can have on plant population and community dynamics, progress has been slow in the directed collection of regeneration traits to inform community assembly outcomes.

While seed mass is globally available and linked to growth and reproductive output, there are limits to its explanatory ability. In this essay, we call for expanded efforts to integrate a more diverse set of regeneration traits into community assembly models.

First, we extend an existing community assembly framework to conceptualize regeneration as a series of transitional processes whose outcomes are …

Dawn Or Doom: The Risks And Rewards Of Emerging Technologies, Diana Hancock, Steve Tally, Gerry Mccartney, Michele Arthur

Purdue P-12 Networking Summit & Poster Session

Dawn or Doom is a free and open to the public conference at Purdue where we focus on benefits and risks surrounding some of the technologies that are both the most disruptive to current practices and being adopted the fastest. A collection of Purdue faculty experts and some outside speakers showcase their many perspectives related to this technology explosion, explore conditions that will foster innovation and investment into the next generation, and address the big-picture issues where both optimism and pessimism are warranted.

A Brief History Of Corn: Looking Back To Move Forward, Jon Derek Pruitt

Doctor of Plant Health Program: Dissertations and Student Research

Maize was domesticated from teosinte in Mexico some 7,000 to 10,000 years ago and quickly spread through the Americas. It has become one of the most important crops at a local and global level. Two types, Northern Flint corn and Southern Dent corns provided the basis of the genetic background of modern maize hybrids. The development of hybrids, first double-cross and later single-cross hybrids, along with a transition to high input farming provided huge yield increases, which have continued to improve with improving technology.

Increase in maize production also caused a rise in Western corn Rootworm (Diabrotica virgifera virgifera …

Genetic Determinism Of Xanthomonas Arboricola Pv. Pruni (Xap) Resistance, Fruit Quality, And Phenological Traits In Peach And Incorporation Of Marker-Assisted Selection (Mas) In The University Of Arkansas Peach And Nectarine Breeding Program, Terrence James Frett

Graduate Theses and Dissertations

For over two decades the incorporation of marker-assisted selection (MAS) has been discussed as an innovative approach to increase peach breeding efficiency. Although hundreds of quantitative trait loci (QTLs) have been identified, only a few have been converted into usable MAS tools. This highlights a disconnect between genomic discoveries and practical application in breeding programs, which has delayed use of MAS.

In this dissertation, three sequential steps were performed with the objective to bridge this gap and develop breeding-relevant DNA tests for MAS of fruit bacterial spot resistance (Xap1 and Xap6), fruit quality [blush (Rf), acidity (D), and acidity and …

Screening Strawberry Clones For Anthracnose Disease Resistance Using Traditional Techniques And Molecular Markers, Melinda A. Miller-Butler

Dissertations

Cultivated strawberry, Fragaria x ananassa Duchesne, is host for many pathogens. One of the most destructive diseases of strawberry is anthracnose, whose symptoms include fruit rot, leaf and petiole lesions, crown rot, wilt, and death. Three species of Colletotrichum are considered causative agents of anthracnose diseases of strawberry. Colletotrichum acutatum causes anthracnose fruit rot, has a broad host range, and occurs in most areas of the world where strawberries are grown. Colletotrichum fragariae, the primary causal fungus of anthracnose crown rot, may infect all aboveground parts of the strawberry plant, and has restricted host and geographic ranges. Colletotrichum gloeosporioides …

Gene Expression And Physiological Analysis To Study Differences Between Oryza Sativa Cultivars Susceptible And Resistant To Chalky Grain Formation Subjected To High Nighttime Temperatures., Nicholas Lawson

Graduate Theses and Dissertations

Starch composition and grain quality of rice is greatly influenced by genotype and environmental factors. The detrimental effects of high nighttime temperatures on rice yield and quality has recently become apparent, with some of the warmest average nighttime temperatures being recorded in the past few years. One of the most notable effects of this stress, an increase in grain chalk formation, correlates with a decrease in quality. This effect varies greatly between cultivars as some show less temperature-sensitive quality reduction than others. The goal of this research is to elucidate fundamental changes that occur in developing plants and grains as …

Influence Of Fatty Acids And Their Derivatives On Aphid Resistance In Arabidopsis And Tomato, Jiamei Li

Graduate Theses and Dissertations

Fatty acid desaturases (FADs) are enzymes that act in the chloroplast or the endoplasmic reticulum (ER) to incorporate double bonds into the acyl chains of fatty acids, and recent evidence indicates that at least one of these enzymes, FAD7, also influences plant resistance to aphids. FAD7 is an enzyme in the chloroplast that is found throughout the plant kingdom and that desaturates 16- and 18-carbon fatty acids (FAs) with two double bonds (dienoic acids) to generate FAs with three double bonds (trienoic acids). In tomato (Solanum lycopersicum) and the model plant Arabidopsis thaliana, mutants with impaired FAD7 function are more …

Consumer Willingness To Pay For Genetically Engineered Edamame, Elijah John Wolfe

Graduate Theses and Dissertations

This study examined the effect of GM labeling on consumer willingness to pay (WTP) for edamame. It also investigated how people reacted to different messages and whether the order of receiving positive or negative information about GM technology impacted their willingness to pay (WTP). The study had three components: (1) a sensory test of GM and non-GM labeled products; (2) a non-hypothetical experimental auction to assess WTP for GM, non-GM and unlabeled products; and (3) a questionnaire to collect demographics and other information from the participants. Results of the sensory evaluation revealed no statistically significant difference between GM and non-GM …

Genetic Analysis Of Soybean Mosaic Virus (Smv) Resistance Genes In Soybean [Glycine Max (L.) Merr.], Mariola Klepadlo

Graduate Theses and Dissertations

Soybean mosaic virus (SMV) causes the most serious viral disease in soybean worldwide. Seven SMV strains, G1 - G7, and three independent multi-allelic loci for SMV resistance, Rsv1, Rsv3, and Rsv4, have been identified. In the initial study, 299 soybean germplasm lines were genotyped for Rsv4 region, inoculated with SMV-G1 and G7 strains, and classified into several resistance groups. The Glyma.02g121400 locus was sequenced from ten soybean accessions, and alignment of the sequences revealed three SNPs displaying 100% polymorphic consistency when a soybean genotype carrying the Rsv4 gene was present. A cross between V94-5152 × Lee 68 was made to …

Preserving Rice Quality: Fine-Mapping And Introgressing A Fissure Resistance Locus, Haley Marie Sater

Graduate Theses and Dissertations

Rice (Oryza sativa L.) kernel fissuring is a major concern of both rice producers and millers. Fissures are small cracks in rice kernels that increase breakage of kernels when milled, and decrease the value of processed rice. This study employed molecular gene tagging methods to fine-map a fissure resistance (FR) locus found in ‘Cybonnet’, a semidwarf tropical japonica cultivar, as well as transfer this trait to rice genotypes of taller, non-semidwarf plant height that are better adapted to some rice production systems. Three QTLs for FR were previously reported; the FR locus with strongest effect resides near the semidwarf sd-1 …