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Full-Text Articles in Life Sciences

Genome-Wide Characterization Of Lateral Organ Boundaries Domain Genes In Sunflower (Helianthus Annuus L.), Saleh M. Aljurbua Jan 2021

Genome-Wide Characterization Of Lateral Organ Boundaries Domain Genes In Sunflower (Helianthus Annuus L.), Saleh M. Aljurbua

Masters Theses

Lateral Organ Boundaries (LBD) gene family encodes transcription factors found only in plants with essential roles in growth, development, and response to biotic and abiotic factors. The sunflower (Helianthus annuus L., Asteraceae family) LBD genes were studied using different in silico and phylogenetic approaches including four major steps: gene identification, phylogenic analysis, structural analysis, and expression analysis. Sixty-four sunflower LBD genes (HaLBDs) were identified using query search of all Arabidopsis LBD genes against sunflower genome (version r1.2) followed by LBD domain sequence verification. A phylogenetic tree was reconstructed using MEGA-X program. The identified genes were phylogenetically classified into two main …


Investigation Of Glutamate Carboxypeptidase Ii Roles In The Folate Cycle Dependent Reproduction And Development Of Caenorhabditis Elegans, Jessica M. Derham Jan 2020

Investigation Of Glutamate Carboxypeptidase Ii Roles In The Folate Cycle Dependent Reproduction And Development Of Caenorhabditis Elegans, Jessica M. Derham

Masters Theses

Glutamate Carboxypeptidase II (GCPII) is a transmembrane, zinc metallopeptidase that is expressed in a wide range of organisms, including roundworms, mice, and humans. In humans, GCPII is primarily expressed in the prostate, kidneys, small intestine, and central nervous system. Within the small intestine, the expected function of GCPII is to aid in the absorption of dietary folate from the intestinal lumen. GCPII cleaves excess glutamates from folate to yield monoglutamated folate which is then readily transported into the enterocyte. Folate can then be used through the one carbon metabolic cycle for the synthesis of nucleotides, conversion of homocysteine to methionine, …


Identification And Analysis Of Genes With Differential And Tissue-Specific Expression In Poplars, Bailey Mitchell Jan 2020

Identification And Analysis Of Genes With Differential And Tissue-Specific Expression In Poplars, Bailey Mitchell

Masters Theses

Poplars have become one of the most frequently studied plant species for their applications in biotechnology, commercial benefits, and ecological importance. Microarray analysis is commonly used to analyze differential gene expression in many organisms. Investigations have examined differential gene expression and performed functional analyses on a single tissue or organ within poplar trees or a closely related set of tissues and organs, but usually do not broadly analyze gene expression across a large number of tissues and organs in poplar. This thesis work aims to generate data on the most differentially expressed genes for the major groups of tissues and …


The Transcriptome Response Of The White-Rot Fungus Trametes Versicolor To Wild-Type And Lignin-Modified Hybrid Poplar, Anbarah Alzabaidi Jan 2020

The Transcriptome Response Of The White-Rot Fungus Trametes Versicolor To Wild-Type And Lignin-Modified Hybrid Poplar, Anbarah Alzabaidi

Masters Theses

Plant biomass is a renewable and sustainable feedstock for biofuel production that can reduce societal dependence on fossil fuels. However, the production of liquid biofuels from the non-starch (i.e. lignocellulosic) material through fermentation technology is limited due to the complexity of the cell wall structure. This necessitates the use of chemical, thermal, and/or mechanical pretreatment technologies, which adds significant capital, operational, and environmental costs. Biological pretreatment strategies have the potential to mitigate these expenses by harnessing the innate ability of specialized bacteria and fungi to deconstruct lignocellulose. White-rot fungi (e.g. Trametes versicolor) have been shown to be …


Exploration Of Sonic Hedgehog Gene Expression In Fathead Minnows (Pimephales Promelas), Brooke Renee Greiner Jan 2019

Exploration Of Sonic Hedgehog Gene Expression In Fathead Minnows (Pimephales Promelas), Brooke Renee Greiner

Undergraduate Honors Theses

Pollutants, as a result of wastewater treatments, have been shown to have negative impacts on aquatic ecosystems. To better understand the possible consequences caused by effluents on ecosystems, it is important to examine ecotoxicology data. One of the most commonly used species for water quality testing is the fathead minnow, Pimephales promelas. Ecotoxicology can then be taken one step further to understand the effects of pollutants on a molecular level. Previous research had identified effluents as causes for abnormal minnow fin morphology. In order to collect additional data on development, tanks with fathead minnows were placed at the Charleston …


A Pipeline For Exogenous Gene Expression And Biomass Analysis In Plants, Bijay Bisunke Jan 2019

A Pipeline For Exogenous Gene Expression And Biomass Analysis In Plants, Bijay Bisunke

Masters Theses

Biological pretreatment of biomass is typically required for the production of liquid biofuels, which are viable alternatives to traditional fossil fuels. While traditional thermomechanical pretreatments are effective at helping to deconstruct lignocellulose, they are often expensive and tend to generate environmentally dangerous waste materials. An alternative to traditional pretreatment strategies is biological pretreatment, which has focused on lignocellulose-degrading organisms, such as white-rot fungi. While direct pretreatment of biomass with white-rot fungi has shown great promise, directly expressing functional white-rot fungi genes in plants (i.e. in planta expression) has the potential to be even more efficient because the biomass itself …


Genomic Dysregulation By Overexpression Of Transcription Factors, Mackenzie Scroggins Jan 2019

Genomic Dysregulation By Overexpression Of Transcription Factors, Mackenzie Scroggins

Undergraduate Honors Theses

As one of the major organs, the liver plays vital roles in the homeostasis of an individual. Being able to identify master regulator genes, genes whose product can affect the activation or deactivation of other genes, will enrich our understanding of hepatic function and liver disease. Previously, our lab used genome-wide microarray data to identify several transcription factors that may play a key role in liver expression. Here we ask whether overexpression of these transcription factors in a non-liver cell would result in liver phenotype activation or general disruption of gene regulation. To this end, we stably introduced seven transcription …


Investigating The Prevalence Of An Insecticide Resistance Gene In Culex Mosquito Populations Of Central Illinois, Kylee R. Noel Jan 2019

Investigating The Prevalence Of An Insecticide Resistance Gene In Culex Mosquito Populations Of Central Illinois, Kylee R. Noel

Masters Theses

The globalization of society has led to the spread of the vectors, mosquitoes, and diseases. Each year millions of people are killed by diseases vectored by mosquitoes. For example, West Nile Virus alone killed over 2,000 people in North America in 2017; 8 of those deaths being in Illinois. Two prominent vectors of West Nile Virus are Culex pipiens and Culex restuans; which are difficult to differentiate based upon morphological features. In this study, mosquitoes collected from two Illinois counties, Coles County and Champaign County, were first identified based upon morphology and this identification was then compared to probe-based …


Detection Of Beta-Lactamase Variants In Municipal Wastewater And Fresh Water, Sunil Pandey Jan 2019

Detection Of Beta-Lactamase Variants In Municipal Wastewater And Fresh Water, Sunil Pandey

Masters Theses

The occurrence and spread of antibiotic-resistant genes (ARGs) are pressing public health problems worldwide. A key factor contributing to the spread of ARGs is lateral gene transfer. Wastewater treatment plants (WWTPs) are measured hot spots of microbial diversity and resistance because they receive polluted wastewater from diverse sources and contain a variety of different environments with dense bacterial loads. Due to the overuse of antibiotics the genetic capacities of microbes have profited. This helps every source of resistance gene and every means of horizontal gene transmission to develop the multiple mechanism of resistance to each antibiotic used clinically, agriculturally, or …


Haplotype Diversity And Population Genetic Structure Of Antistrophus Gall Wasps Associated With Two Silphium Species And Implication For Host Mediated Speciation, Jiaxin Deng Jan 2019

Haplotype Diversity And Population Genetic Structure Of Antistrophus Gall Wasps Associated With Two Silphium Species And Implication For Host Mediated Speciation, Jiaxin Deng

Masters Theses

Gall making insects form a special feeding guild of phytophagous animals, and by manipulating host plant tissue differentiation, are able to avoid plant chemical defenses and thus have no need for counter defense mechanisms. Host plant selection is crucial to the evolution of these insects because successful gall formation is largely dependent on host plant ability to respond to stimuli. In Illinois and neighboring states, Antistrophus gall wasps associated with the rosin weed (S. integrifolium) and the cup plant (S. perfoliatum) are morphologically indistinguishable and thus have been treated as belonging to single species. However, the wasps from the host …


Creg1: Its Role As A Master Regulator Of Liver Function, Iffat Jahan Jan 2019

Creg1: Its Role As A Master Regulator Of Liver Function, Iffat Jahan

Masters Theses

Mammalian development involves a complex system of regulatory signals and reactions resulting in highly differentiated cell types with specific structure and function. The liver is a major organ that has been studied extensively to understand underlying genetic processes responsible for specification, establishment and maintenance of tissue identity. Hepatoma and hepatoma variant cell lines have been used as models to understand genetic networks responsible for liver function. Whole genome microarray analysis of hepatocyte cell lines has revealed candidate genes that may serve as regulators or master regulators of liver specificity. In two previous studies in our lab, the role of candidate …


The Role Of Prrx1 And Snai2 As Master Regulators Of Fibroblast Identity, Huda A. Alzahrani Jan 2018

The Role Of Prrx1 And Snai2 As Master Regulators Of Fibroblast Identity, Huda A. Alzahrani

Masters Theses

Mammalian development involves a complex system of regulatory signals and reactions, leading to the creation of distinct tissues with specific structures and functions controlled by various gene expression profiles. Tissue-specific gene expression is by controlled specific combinations of transcription factors and cofactors that dictate cell differentiation via activation and repression of genes in mammalian cells.

Whole genome microarray analyses of fibroblasts have revealed candidate genes that may serve as master regulators of fibroblast identity, such as Prrx1 and Snai2, that activate downstream genes such as Bmp3, Twist, Shox2, Cfos, Slug, Sema3A, Spp1, and Col1a1. A previous study showed that Prrx1 …


The Transcriptional Response Of Trametes Versicolor To Growth On Maple Chips And Miscanthus Straw, Maha Alanazi Jan 2018

The Transcriptional Response Of Trametes Versicolor To Growth On Maple Chips And Miscanthus Straw, Maha Alanazi

Masters Theses

This thesis research explored the transcriptional response of Trametes versicolor, a white-rot fungus, in response to fundamentally different types of lignocellulosic biomass (miscanthus and maple) and rich medium (malt extract agar). After five weeks of growth by the fungus on the biomass, the fungal RNA was extracted from three biological replicates per biomass type and mRNA was sequenced (approximately 30 million reads per sample). The reads were processed using ArrayStar to covert to RPKM and annotated using JGI's T. versicolor GO annotation file along with NCBI's BLAST. Comparisons were made between average gene expression of the fungus grown on …


The Role Of Creg1 As A Master Regulator Of Liver Function, Abdulrahman Siran Aldaghmi Jan 2017

The Role Of Creg1 As A Master Regulator Of Liver Function, Abdulrahman Siran Aldaghmi

Masters Theses

The liver is known as the chemical factory of the body because it performs a wide range of biochemical functions required for life. Since the liver has such an important role in regulation of normal physiological processes, liver diseases cause a high rate of morbidity and mortality. Therefore, understanding the mechanisms of liver development will shed light on the causes of liver disease. In this study, a cell line model that utilizes rat hepatoma cells (Fg14) and hepatoma variant cells (H11) was used to identify master regulators of liver gene expression. Whole genome expression studies identified the gene CREG1 (Cellular …


Dna Markers Identify Genetic Heritage Between Chickadees Near A Contact Zone In Illinois, Fahad M. Alshammari Jan 2017

Dna Markers Identify Genetic Heritage Between Chickadees Near A Contact Zone In Illinois, Fahad M. Alshammari

Masters Theses

I studied the genetic interactions of Black-capped (Poecile atricapilus) (BCCH) and Carolina (P. carolinensis) (CACH) Chickadees in and near the largest hybrid contact zone in Illinois. Biologists have assumed Carolina and Black-capped Chickadees hybridize in their large contact zone in Bond and Fayette Counties, based on intermediate morphological measurements, plumage characteristics and the production of aberrant vocalizations. In determining hybridization, however, diagnostic genetics may be more useful than any other criterion. The genetic and environmental factors that have contributed to the survival of this chickadees hybrid zone have underscored the genetic integrity of both species. We …


Expression, Purification, And Characterization Of An Intrinsically Disordered Late Embryogenesis Abundant (Lea) Protein From Artemia Franciscana Utilizing Escherichia Coli And Nicotiana Tabacum, Md Fazlul Karim Jan 2017

Expression, Purification, And Characterization Of An Intrinsically Disordered Late Embryogenesis Abundant (Lea) Protein From Artemia Franciscana Utilizing Escherichia Coli And Nicotiana Tabacum, Md Fazlul Karim

Masters Theses

Anhydrobiosis is an astounding strategy that allows certain species (both animals and plants) to survive severe environmental conditions such as desiccation, extreme cold, or heat in the habitat. Despite the occurrence of several different molecular strategies, expression of highly hydrophilic polypeptides termed LEA proteins has been most conclusive identified as a requirement for the survival of plants and animals during periods of water stress such as freezing and drying. Several classification schemes for LEA proteins have been proposed and the brine shrimp, Artemia franciscana, is the only known animal that naturally expresses LEA proteins from three different classification groups …


Detection Of Antibiotic Resistance Loci In Wastewater And Fresh Water Samples, Mohammed Hamed Almalki Jan 2017

Detection Of Antibiotic Resistance Loci In Wastewater And Fresh Water Samples, Mohammed Hamed Almalki

Masters Theses

Proper treatment of municipal wastewater is important not only for prevention of eutrophication but also for public health concerns. One consideration for wastewater treatment is the presence of organisms carrying antibiotic resistance genes. If these organisms survive the wastewater treatment process and are released into the streams, they can pose significant risks to public health. In addition, their presence also raises concerns for lateral gene transfer events at the wastewater plant. The spread of antibiotic loci has a major impact in public health and clinical therapy because resistant organisms render conventional treatments of important illnesses difficult. Beta-lactam drugs are known …


The Transcriptome Response Of The White-Rot Fungus Phanerochaete Chrysosporium To Maple And Miscanthus, Mashael Rashed Alaradi Jan 2017

The Transcriptome Response Of The White-Rot Fungus Phanerochaete Chrysosporium To Maple And Miscanthus, Mashael Rashed Alaradi

Masters Theses

Lignocellulosic biomass is a valuable feedstock for the production of liquid biofuels. However, liquid biofuel production from lignocellulose is economically challenging due to the difficulties associated with separating the cellulosic sugars from lignin. In addition, the current thermochemical methods to deconstruct lignocellulose typically involve hazardous chemicals that can negatively impact the environment. Recent studies have demonstrated the efficacy of white-rot fungi as alternative pretreatment agents that can lower the costs of lignocellulose deconstruction and reduce negative impacts on the environment. However, understanding of the biochemical mechanisms of lignocellulose breakdown used by these fungi is limited, particularly with respect to the …


Low-Head Dams On Habitat, Fish Functional Guilds And Genetic Structuring In A Midwestern River System, Shannon Cassandra Frary Smith Jan 2016

Low-Head Dams On Habitat, Fish Functional Guilds And Genetic Structuring In A Midwestern River System, Shannon Cassandra Frary Smith

Masters Theses

The natural flow regime of the majority of rivers in the United States has been altered by anthropogenic structures. This loss of connectivity plays a strong role in shaping river ecosystems by altering physical habitat characteristics and shaping fish community assemblages. Although the impacts of large dams on river systems are well documented and often easy to observe, there are fewer studies on the effects of smaller low-head dams. Additionally, the influences of low-head dams on the genetic structuring of small-bodied riverine fishes have yet to be fully explored. I assessed the effects of two low-head dams on the Vermilion …


Genetic Structure And Diversity Of Channel Catfish (Ictalurus Punctatus) In Three Large Midwestern Rivers, Vaclav Alexei Sotola Jan 2016

Genetic Structure And Diversity Of Channel Catfish (Ictalurus Punctatus) In Three Large Midwestern Rivers, Vaclav Alexei Sotola

Masters Theses

Little information is available regarding the genetic structure and diversity of sportfishes in large rivers, which can be vital to continuing the sustainable exploitation of these fisheries. Additionally, impoundments often have vast impacts on riverine systems. These impacts include altering the flow regime, changing the nutrient load, and preventing migratory fish from reaching their spawning grounds. If fishes are prevented from reaching their spawning grounds, their genetic diversity and structuring could begin to change relative to historic measures, potentially decreasing their fitness and ability to survive. I screened microsatellite loci to assess the genetic population structure and diversity of channel …


Impact Of Transcription Factors On Fibroblast Specific Gene Silencing In Somatic Cell Hybrids, Tania Ray Jan 2016

Impact Of Transcription Factors On Fibroblast Specific Gene Silencing In Somatic Cell Hybrids, Tania Ray

Masters Theses

As totipotent cells differentiate to specific cell types in multicellular organisms, certain sets of genes are turned off (gene silencing/gene extinction) while others are turned on (gene activation). Cell type specific gene silencing and gene activation is the basis of cell differentiation. Somatic cell hybrids which are produced by fusing different types of somatic cells from two different tissues have been used as a valuable resource to discern the phenomenon of lineage- specific gene extinction. Identification of regulatory factors that mediate gene extinction in hybrids are key to understanding regulatory mechanisms that govern cell differentiation in a multicellular organism. Transcription …


Genome Wide Analysis Of Hepatic Gene Silencing In Mammalian Cell Variants, Jeffrey L. Kurkewich May 2012

Genome Wide Analysis Of Hepatic Gene Silencing In Mammalian Cell Variants, Jeffrey L. Kurkewich

Undergraduate Honors Theses

Using microarray data, a genome wide analysis of hepatic gene-silencing in four hepatoma variant cell lines was carried out. The purpose of this analysis was to identify candidate genes that may be able to restore liver function in non-functional cell variants, ultimately giving insight into the mechanisms behind global hepatic gene expression. Based on a selection scheme allowing only for genes activated or repressed at least 5 fold in 2 out of the 4 variant cell lines, 225 genes were found to be repressed while a total of 76 genes were found to be activated. Of the repressed genes identified, …


Investigation Of Matrilineal Relationships Via Mitochondrial Dna In The Southeastern Yellowjacket (Vespula Squamosa), Anthony Deets Jan 2003

Investigation Of Matrilineal Relationships Via Mitochondrial Dna In The Southeastern Yellowjacket (Vespula Squamosa), Anthony Deets

Masters Theses

The question of whether and how apparently "altruistic" behaviors can evolve in social animals has received an enormous amount of attention from evolutionary biologists and has been termed "the central theoretical problem of sociobiology". Thus, recent interest is eusocial species with coexisting multiple queens stems from the realization that the genetic relatedness of individuals in such colonies presents additional theoretical challenges beyond those addressed by the Hamiltonian model of kin selection and lengthens the potential list of reproductive conflicts of interest.

The Southeastern Yellowjacket (Vespula squamosa) exhibits two social forms sympatrically in the southern parts of its range. These two …


Mitochondrial Dna And Microsatellite Genetic Variation Of Dollar Sunfish (Lepomis Marginatus), Nancy A. Schable Jan 2002

Mitochondrial Dna And Microsatellite Genetic Variation Of Dollar Sunfish (Lepomis Marginatus), Nancy A. Schable

Masters Theses

Dollar sunfish (Lepomis marginatus) at the Savannah River Site were sampled from two radiocesium contaminated ponds with a history of thermal elevation and from reference ponds with no history of radioactive or thermal contamination. Fluorescent sequencing of a portion of the mitochondrial control region showed no genetic variation within or between populations. Centrarchidae microsatellite loci Lma 120 (6 alleles, N=124 from 5 populations), Lma 20 (10 alleles, N=37 from 3 populations) and Rb 7 (14 alleles. N=17 from 2 populations) were variable for dollar sunfish. An additional 9 microsatellite primer pairs were designed for dollar sunfish. Testing of the designed …


Phylogeography And Genetic Diversity Of The Seal Salamander (Desmognathus Monticola), Erin D. Casey Jan 2002

Phylogeography And Genetic Diversity Of The Seal Salamander (Desmognathus Monticola), Erin D. Casey

Masters Theses

Phylogeography is defined as the spatial distribution of taxa with respect to geologic and geographic events. It is well documented that the distributions of many taxa have been affected by glacial events during the Pleistocene Era. The patterns generated can be very complex and result from shifts in climate and/or vegetation.

The Seal salamander, (Desmognathus monticola), is one species that still has questions pertaining to its phylogeography. The range of this species extends from southwestern Pennsylvania to northern Alabama and Georgia, with a highly disjunct, state-endangered population in the Red Hills of Alabama. The main goal of this study …


Comparisons Of Genetic Variance And Physiological Responses In Two Populations Of Western Mosquitofish, Gambusia Affinis, Brett Egger Jan 1997

Comparisons Of Genetic Variance And Physiological Responses In Two Populations Of Western Mosquitofish, Gambusia Affinis, Brett Egger

Masters Theses

The study was conducted to determine the effects of lowered genetic variance in the Western mosquitofish (Gambusia affinis) on the physiological parameters of critical thermal maximum and minimum pH. Mosquitofish were obtained from two small central Illinois ponds, Lost Pond and Shadow Pond, by seines and dip nets. Once caught, fish were returned to the laboratory and acclimated for a minimum of five days at a temperature of 27°C and a pH of 8.25. At the beginning of each experimental run, fish were subjected to the physiological experiments for determination of critical thermal maximum and minimum pH, and then measured …


Biochemical Systematics Of Notothenioid Fishes From Antarctica, Mara A. Mcdonald, Michael H. Smith, Michael W. Smith, James M. Novak, Paul E. Johns, Arthur L. Devries Jan 1992

Biochemical Systematics Of Notothenioid Fishes From Antarctica, Mara A. Mcdonald, Michael H. Smith, Michael W. Smith, James M. Novak, Paul E. Johns, Arthur L. Devries

Faculty Research & Creative Activity

Genetic variation at 30 protein-coding loci was examined in seven forms of notothenioid fishes from Antarctica. Multilocus heterozygosity varied from 0.018 to 0.078 across taxa. An analysis of the allozyme data revealed the probable existence of an unrecognized cryptic species within Trematomu5 bemacchii. Pagothenia borchgrevinki is as closely related to some species of Trematomus as are some species of Trematomus to each other. Speciation among the species of Trematomus and Pagothenia appears to have taken place primarily after the separation of Antarctica from Australia.


A Biosystematic Study Of Panus Conchatus (Basidiomycetes; Agaricales), James Edward Johnson Jan 1992

A Biosystematic Study Of Panus Conchatus (Basidiomycetes; Agaricales), James Edward Johnson

Masters Theses

As part of a biosystematic study of Panus conchatus (Bull.: Fr.) Fr., North American and European herbarium specimens from the Field Museum and the University of Michigan were examined and a description of the taxon prepared. Tissue and single spore isolates were obtained from basidiocarps collected in Illinois. Single and polyspore isolates were obtained from a collection made in Switzerland by R. H. Petersen. Culture mat analyses were completed on several media and the taxonomic value of cultural characters assessed. Based on this study, the identification of somatic cultures by cultural characteristics is unlikely. Single spore isolates from the Illinois …


Partial Characterization Of Lpss From Rhizobium Fredii Usda 205 Before And After Nod Gene Induction, Bradley Lawrence Reuhs Jan 1988

Partial Characterization Of Lpss From Rhizobium Fredii Usda 205 Before And After Nod Gene Induction, Bradley Lawrence Reuhs

Masters Theses

The lipopolysaccharides (LPS) from Rhizobium fredii USDA 205 and its nod- mutant, HC 205, which has been cured of the 192-MDa symbiotic plasmid, were isolated by the phenol-water extraction method. The LPS from the wild-type strain which was grown in association with host-plant root extract or a flavone analog to a constituent of the root extract, which is required for the induction of at least a portion of the nodulation genes, was also isolated. The conditions required for the induction of the nod genes were determined by work with a nod- mutant of R. fredii USDA 201 which …


Use Of Monolploid Solanum Phureja In Cell And Tissue Culture Techniques For Potato Improvement, Henry R. Owen Jul 1987

Use Of Monolploid Solanum Phureja In Cell And Tissue Culture Techniques For Potato Improvement, Henry R. Owen

Faculty Research & Creative Activity

Monoploid genotypes (2n = x = 12), derived by anther culture of a diplandrous genotype of Solanum phureja, a South-American diploid potato species, were examined for their utility in germplasm development.

Nine monoploid genotypes and the diploid anther-donor plant were grown in photoperiod chambers at The Southeastern Plant Environment Laboratories (SEPEL) at North Carolina State University to examine the effect of photoperiod on tuber yield and to determine the variability for critical photoperiod for tuberization. Significant differences were found among the monoploid genotypes for total tuber weight and tuber number. Longer photoperiod treatments both decreased and delayed tuberization. Axillary tuber …