Plant Biology Commons^™

Limited Mitogenomic Degradation In Response To A Parasitic Lifestyle In Orobanchaceae, Weishu Fan, Andan Zhu, Melisa Kozaczek, Neethu Shah, Natalia Pabón-Mora, Favio González, Jeffrey P. Mower

Center for Plant Science Innovation: Faculty Publications

In parasitic plants, the reduction in plastid genome (plastome) size and content is driven predominantly by the loss of photosynthetic genes. The first completed mitochondrial genomes (mitogenomes) from parasitic mistletoes also exhibit significant degradation, but the generality of this observation for other parasitic plants is unclear. We sequenced the complete mitogenome and plastome of the hemiparasite Castilleja paramensis (Orobanchaceae) and compared them with additional holoparasitic, hemiparasitic and nonparasitic species from Orobanchaceae. Comparative mitogenomic analysis revealed minimal gene loss among the seven Orobanchaceae species, indicating the retention of typical mitochondrial function among Orobanchaceae species. Phylogenetic analysis demonstrated that the mobile cox1 …

Identification Of Homogentisate Dioxygenase As A Target For Vitamin E Biofortification In Oilseeds, Minviluz G. Stacey, Rebecca E. Cahoon, Hanh T. Nguyen, Yaya Cui, Shirley Sato, Cuong T. Nguyen, Nongnat Phoka, Kerry M. Clark, Yan Liang, Joe Forrester, Josef Batek, Phat Tien Do, David A. Sleper, Thomas E. Clemente, Edgar B. Cahoon, Gary Stacey

Center for Plant Science Innovation: Faculty Publications

Soybean (Glycine max) is a major plant source of protein and oil and produces important secondary metabolites beneficial for human health. As a tool for gene function discovery and improvement of this important crop, a mutant population was generated using fast neutron irradiation. Visual screening of mutagenized seeds identified a mutant line, designated MO12, which produced brown seeds as opposed to the yellow seeds produced by the unmodified Williams 82 parental cultivar. Using forward genetic methods combined with comparative genome hybridization analysis, we were able to establish that deletion of the GmHGO1 gene is the genetic basis of …

The Chemical Constituents Of New Essential Oils From Endemic And Sub Endemic Plants Of Mongolian Gobi, Sanduin Shatar, Jordanka Stavena, Milka Todorova, Shataryn Altantsetseg

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

The new essential oil-Endemic and sub endemic plants in Outer Mongolian Gobi were isolated by hydro distillation from the aerial parts of Brachanthemum gobicum Krasch, B. mongolicum Krach, B. mongolorum Grub., Asterothamnus centrali-asiaticus Novopork, A. molliusculus Novopork., Ajania trifida (Turcz) Tzvel, A. achilleoides (Turcz) Tzvel., Ferula ferulaeoides (Stend) Eug. Kor., Artemisia davajamczii Darijima., A. caespitosa Ldb, A. subchrysolepis Filat, A. schischkinii Krasch, A.intricata Franch, A.ordasica Krasch, A.gobica (Krasch) Grub., A. sphalerocephala Krasch that grown in wild in Outer Mongolian Gobi. The essential oils were analyzed by a combination of Capillary GC and GC-MS and their main constituents were described.

Temporal Dynamics Of Maize Plant Growth, Water Use, And Leaf Water Content Using Automated High Throughput Rgb And Hyperspectral Imaging, Yufeng Ge, Geng Bai, Vincent Stoerger, James C. Schnable

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Automated collection of large scale plant phenotype datasets using high throughput imaging systems has the potential to alleviate current bottlenecks in data-driven plant breeding and crop improvement. In this study, we demonstrate the characterization of temporal dynamics of plant growth and water use, and leaf water content of two maize genotypes under two different water treatments. RGB (Red Green Blue) images are processed to estimate projected plant area, which are correlated with destructively measured plant shoot fresh weight (FW), dry weight (DW) and leaf area. Estimated plant FW and DW, along with pot weights, are used to derive daily plant …

Decipher The Molecular Response Of Plant Single Cell Types To Environmental Stresses, Mehrnoush Nourbakhsh-Rey, Marc Libault

Department of Agronomy and Horticulture: Faculty Publications

The analysis of the molecular response of entire plants or organs to environmental stresses suffers from the cellular complexity of the samples used. Specifically, this cellular complexity masks cell-specific responses to environmental stresses and logically leads to the dilution of the molecular changes occurring in each cell type composing the tissue/organ/plant in response to the stress.Therefore, to generate a more accurate picture of these responses, scientists are focusing on plant single cell type approaches. Several cell types are now considered as models such as the pollen, the trichomes, the cotton fiber, various root cell types including the root hair cell, …

Draft Genome Sequence Of Erwinia Tracheiphila, An Economically Important Bacterial Pathogen Of Cucurbits, Lori R. Shapiro, Erin D. Scully, Dana Roberts, Timothy J. Straub, Scott M. Geib, Jihye Park, Andrew G. Stephenson, Erika Salaau Rojas, Quin Liu, Gwyn Beattie, Mark Gleason, Consuelo M. De Moraes, Mark C. Mescher, Shelby G. Fleischer, Roberto Kolter, Naomi Pierce, Olga Zhaxybayeva

Department of Agronomy and Horticulture: Faculty Publications

Erwinia tracheiphila is one of the most economically important pathogens of cucumbers, melons, squashes, pumpkins, and gourds in the northeastern and midwestern United States, yet its molecular pathology remains uninvestigated. Here, we report the first draft genome sequence of an E. tracheiphila strain isolated from an infected wild gourd (Cucurbita pepo subsp. texana) plant. The genome assembly consists of 7 contigs and includes a putative plasmid and at least 20 phage and prophage elements.

Effects Of Seed Applied Fungicide On Arbuscular Mycorrhizal Colonization Of South Dakota Cultivars Of Oat, Soybean, And Corn, Jesse Cameron

Electronic Theses and Dissertations

Arbuscular mycorrhizal fungi (AMF) are obligate symbionts that form a mutualistic relationship with approximately 80% of terrestrial plant species. These obligate symbionts have a generally beneficial effect on their host such as increased nutrient acquisition, better tolerance to biotic and abiotic stresses, and the improvement of soil qualities. Due to the recent, widespread use of seed applied fungicides on row crops in the U.S. Midwest, there are concerns that the fungicides will inhibit these beneficial mycorrhizae. This study was conducted to evaluate what effect different commonly used seed applied fungicides have on AMF in the presence of different varieties of …

A Molecular Genetic And Physiological Comparison Of The Hybrid Necrosis Response In Wheat (Triticum Aestivum L.) To Biotic And Abiotic Stress Responses, Devi R. Kandel

Electronic Theses and Dissertations

Expression of hybrid necrosis in plants can lead to a significant reduction in productivity, or even lethality. Epistatic interactions between divergent loci that have evolved through evolution are proposed as being responsible for the genetic incompatability that is expressed as hybrid necrosis. Hybrid necrosis can also represent an obstacle to the transfer of desirable traits from wild, related species to domesticated bread wheat. In wheat, expression of dominant complementary genes Ne1 and Ne2, located to chromosomes 5B and 2B in a hybrid results the production of necrotic leaf tissue, stunted plant growth, and reduced grain yield, which are similar plant …

Evaluation And Identification Of Soybean Aphid Resistance Sources And Mapping Of Soybean Aphid Resistance Loci In Early Maturing Soybean Germplasm Accessions, Siddhi Jeewan Bhusal

Electronic Theses and Dissertations

Soybean aphid (Aphis glycines Matsumura) has been a major pest of soybean [Glycine max (L.) Merr.] in North America particularly in the northern United States and three Canadian provinces. At least four biotypes of soybean aphid have been confirmed in the United States. Identification of soybean aphid resistance sources in early-maturing soybeans and genetic characterization of new sources of resistance will facilitate to expand the gene pool of soybean aphid resistance and thus will help to develop soybean aphid resistant cultivars. To identify new sources of resistance in early maturing soybeans, 330 soybean germplasm accessions from Maturity Group (MG) I, …

Cooperation And Punishment In The Arbuscular Mycorrhizal Symbiosis: Implications For Resource Exchange & Biological Market Dynamics, Jerry A. Mensah

Electronic Theses and Dissertations

The arbuscular mycorrhizal (AM) symbiosis is arguably the world’s most abundant and important mutualism, and brings together the roots of the majority of land plants and AM fungi to great mutual advantage. The AM symbiosis can increase the uptake of nutrients, such as phosphorus (P) and nitrogen (N), and improves the abiotic and biotic stress resistance of the host plant. AM fungi have the potential to act as biofertilizers and bioprotectors in sustainable agriculture. However, despite its significance, the mechanisms that control the resource exchange between both partners in the arbuscular mycorrhizal symbiosis are largely unknown. The main aim of …

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 …

2016 Virginia Wildflower Of The Year: Downy Rattlesnake Plantain, Goodyera Pubescens, W. John Hayden

Biology Faculty Publications

Regardless of season, Downy Rattlesnake Plantain is a delight to encounter in the woods of Virginia. This evergreen orchid is a perennial rhizomatous herb of the forest floor. The horizontal rhizomes, usually covered lightly by leaf litter, bear roots at intervals and terminate in a rosette of leaves. Leaves are alternate, somewhat crowded together, and only slightly elevated above ground level. Leaf blades are ovate, 3–8 cm long, and 1.5–3 cm wide, often of varying size within a rosette. Leaves are present year-round, bluish-green, with prominent white veins; on each leaf, a broad midvein is flanked by two smaller veins …

Triticum Mosaic Virus Exhibits Limited Population Variation Yet Shows Evidence Of Parallel Evolution After Replicated Serial Passage In Wheat, Melissa S. Bartels, Roy French, Robert A. Graybosch, Satyanarayana Tatineni

Department of Plant Pathology: Faculty Publications

An infectious cDNA clone of Triticum mosaic virus (TriMV) (genus Poacevirus; family Potyviridae) was used to establish three independent lineages in wheat to examine intra-host population diversity levels within protein 1 (P1) and coat protein (CP) cistrons over time. Genetic variation was assessed at passages 9, 18 and 24 by single-strand conformation polymorphism, followed by nucleotide sequencing. The founding P1 region genotype was retained at high frequencies in most lineage/passage populations, while the founding CP genotype disappeared after passage 18 in two lineages.We found that rare TriMV genotypes were present only transiently and lineages followed independent evolutionary trajectories, …

Foliar Fungicide Application Timing For Disease Management, Stay Green, And Yield In Nebraska, 2015, J. D. Harbour, T. A. Jackson-Ziems

Department of Plant Pathology: Faculty Publications

The objective of the trial was to compare foliar fungicides applied at different corn growth stages for gray leaf spot (GLS) and southern rust (SR) efficacy. Irrigated corn was grown based on Nebraska Extension irrigation recommendations at the South Central Ag Lab near Clay Center, NE. Soils were a silt loam with 6.7 pH and 1.8 % organic matter, and the previous crop was soybean. Reduced tillage was performed to the field prior to planting. Corn (DKC 65-79 RIB, tolerant to GLS) was planted at approximately 34,000 seed/A on 26 May, which is later than normal, due to wet spring …

Foliar Fungicide Modes Of Action For Southern Rust Management, Push Lodging, And Yield In Nebraska, 2015, J. D. Harbour, T. A. Jackson-Ziems

Department of Plant Pathology: Faculty Publications

The objective of the trial was to compare foliar fungicides with different modes of action for southern rust (SR) efficacy. Irrigated corn was grown based on Nebraska Extension irrigation recommendations at the South Central Ag Lab near Clay Center, NE. Soils were a silt loam with 6.7 pH and 1.8 % organic matter, and the previous crop was soybean. Reduced tillage was performed to the field prior to planting. Corn (DKC 65-79 RIB, tolerant to gray leaf spot (GLS)) was planted at approximately 34,000 seed/A on 26 May. Eight treatments were arranged in a randomized complete block design with six …

Deposition Aid Adjuvants Plus A Fungicide For Southern Rust Management, Stay Green, Push Lodging, And Yield Comparisons In Field Corn In Nebraska, 2015, J. D. Harbour, T. A. Jackson-Ziems

Department of Plant Pathology: Faculty Publications

The objective of the trial was to compare foliar fungicides for southern rust (SR) efficacy. Irrigated corn was grown based on Nebraska Extension irrigation recommendations at the South Central Ag Lab near Clay Center, NE. Soils were a silt loam with 6.7 pH and 1.8 % OM and the previous crop was soybean. Reduced tillage was performed to the field prior to planting. Corn (DKC 65-79 RIB, tolerant to gray leaf spot (GLS)) was planted at approximately 34,000 seed/A on 26 May. Eleven treatments were arranged in a randomized complete block design with six replications. . . . Phytotoxicity was …

Root-Lesion Nematodes, T. A. Jackson-Ziems

Department of Plant Pathology: Faculty Publications

Root-lesion nematodes, Pratylenchus spp., are among the most commonly encountered plant-parasitic nematodes, with one or more species occurring in almost every field. Their small size (0.4-0.7 mm long) relative to most other plant-parasitic nematodes enables them to survive in almost any soil texture. Their wide host range and distribution make them one of the most damaging nematodes worldwide, ranging from cool temperate to tropical environments. At least eight species of root-lesion nematodes have been associated with sunflower.

Root-Knot Nematodes, T. A. Jackson-Ziems

Department of Plant Pathology: Faculty Publications

Root-knot nematodes, Meloidogyne spp., are some of the most damaging plant pathogens. Several of the most common species of root-knot nematodes have been confirmed to reproduce and cause damage on sunflower, including M. arenaria, M. hapla, M. incognita, M. javanica, and M. hispanica.

Meloidogyne spp. occur worldwide but are especially common in temperate, subtropical, and tropical regions. Countries where Meloidogyne spp. have been confirmed to affect sunflower include the United States and the African nations of Egypt, Mozambique, South Africa, and Zambia. Root-knot nematodes tend to cause the most damage to plants grown in sandy …

Northern Corn Leaf Blight, Tamra A. Jackson-Ziems

Department of Plant Pathology: Faculty Publications

Northern corn leaf blight (NCLB) is a disease of corn caused by a fungus, Exserohilum turcicum (sexual stage Setosphaeria turcica). Its development is favored by cool to moderate temperatures and high relative humidity. Historically, NCLB has been more common and severe in states in the eastern Corn Belt, but its incidence has increased in Nebraska and the western Corn Belt in recent years. The disease is distributed throughout most of the corn-growing areas of the United States. The disease also occurs sporadically throughout other humid corn-producing areas of the world. In Nebraska, the disease has been most serious in …

Identification Of Erwinia Rhapontici As The Causal Agent Of Crown And Shoot Rot And Pink Seed Of Pea In Nebraska, Anthony O. Adesemoye, Hsin-Ho Wei, Robert M. Harveson

Department of Plant Pathology: Faculty Publications

Over the last five years, the production of dry yellow peas (Pisum sativum L.) has been increasing in Nebraska and other areas of the Central High Plains, according to a USDA report (Jasa 2013). Dry pea is a short-season crop with a low water requirement, making it a good rotational crop for the high plains. We have noted bacterial pathogens, potentially a disease complex, that may negatively impact the production of pea in this region, and one of the emerging pathogens is Erwinia rhapontici. This pathogen is a gram-negative bacterium that has been reported from soil, seed, and …