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Basa Regulates Cell Wall Organization And Asexual/Sexual Sporulation Ratio In Aspergillus Nidulans, Shaojie Li, Dapeng Bao, Gary Yuen, Steven D. Harris, Ana M. Calvo

Department of Plant Pathology: Faculty Publications

Sphingolipid C4 hydroxylase catalyzes the conversion of dihydrosphingosine to phytosphingosine. In Saccharomyces cerevisiae, Sur2 is essential for sphingolipid C4 hydroxylation activity but not essential for normal growth. Here we demonstrate that the Aspergillus nidulans Sur2 homolog BasA is also required for phytosphingosine biosynthesis but is also essential for viability. We previously reported that a point missense mutation in basA resulted in aberrant cell wall thickening. Here our data suggest that accumulation of dihydrosphingosine is responsible for this phenotype. In addition, two different mutations in basA consistently accelerated the transition from asexual development to sexual development compared to the wild-type …

Free-Living Dorylaimid Nematodes From Nature Reserves In Costa Rica. The Genus Pachydorylaimus Siddiqi, 1983, A. Esquivel, P. Guerrero, R. Peña-Santiago, Thomas O. Powers

Department of Plant Pathology: Faculty Publications

A taxonomic study of three species, two known and one new, belonging to the genus Pachydorylaimus Siddiqi, 1983 from natural areas in Costa Rica is presented. Pachydorylaimus holovachovi sp. n. is described and can be distinguished by its body 0.90-1.00 mm long, lip region 14-17 μm wide, odontostyle 13-15 μm long, odontophore morphology with differentiated hyaline spindle-shaped area surrounding its junction to pharyngeal lining but lacking distinct basal flanges, total stylet length 35- 44 μm, pars refringens vaginae absent, V = 43-47, female tail straight and tapering to an acute tip (57- 78 μm, c = 12.5-15.8, c’ = 2.0-3.0), …

Fertility Restoration Of The Sorghum A3 Male-Sterile Cytoplasm Through A Sporophytic Mechanism Derived From Sudangrass, Hoang V. Tang, Jeffrey F. Pedersen, Christine D. Chase, Daryl R. Pring

Department of Agronomy and Horticulture: Faculty Publications

Fertility restoration of sorghum [Sorghum bicolor (L.) Moench] lines carrying the IS1112C (A3 group) male-sterile cytoplasm has been documented as a two-gene gametophytic mechanism involving complementary action of restoring alleles designated Rf3 and Rf4, as derived from IS1112C. Fertility restoration capability has also been reported from sudangrass (S. bicolor subsp. drummondii) populations. We describe characteristics of a fertility restoration system derived from sudangrass, in which male-sterile individuals were observed at high frequency in backcross and F₂-F₃ segregating populations. Segregation analyses were consistent with a sporophytic restoration system involving two complementary genes. Pollen iodine …

Publishing Ltd Whole-Plant Mineral Partitioning Throughout The Life Cycle In Arabidopsis Thaliana Ecotypes Columbia, Landsberg Erecta, Cape Verde Islands, And The Mutant Line Ysl1ysl3, Brian M. Waters, Michael A. Grusak

Department of Agronomy and Horticulture: Faculty Publications

• Minimal information exists on whole-plant dynamics of mineral flow through Arabidopsis thaliana or on the source tissues responsible for mineral export to developing seeds. Understanding these phenomena in a model plant could help in the development of nutritionally enhanced crop cultivars. • A whole-plant partitioning study, using sequential harvests, was conducted to characterize growth and mineral concentrations and contents of rosettes, cauline leaves, stems, immature fruit, mature fruit hulls, and seeds of three WT lines (Col-0, Ler, and Cvi) and one mutant line (Col-0::ysl1ysl3). • Shoot mineral content increased throughout the life cycle for all minerals, although tissue-specific mineral …

A Soybean Transcript Map: Gene Distribution, Haplotype And Single-Nucleotide Polymorphism Analysis, Ik-Young Choi, D. L. Hyten, Lakshmi K. Matukumalli, Qijian Song, Julian M. Chaky, Charles V. Quigley, Kevin Chase, K. Gordon Lark, Robert S. Reiter, Mun-Sup Yoon, Eun-Young Hwang, Seung-In Yi, Nevin D. Young, Randy C. Shoemaker, Curtis P. Van Tassell, James E. Specht, P. B. Cregan

Department of Agronomy and Horticulture: Faculty Publications

The first genetic transcript map of the soybean genome was created by mapping one SNP in each of 1141 genes in one or more of three recombinant inbred line mapping populations, thus providing a picture of the distribution of genic sequences across the mapped portion of the genome. Singlenucleotide polymorphisms (SNPs) were discovered via the resequencing of sequence-tagged sites (STSs) developed from expressed sequence tag (EST) sequence. From an initial set of 9459 polymerase chain reaction primer sets designed to a diverse set of genes, 4240 STSs were amplified and sequenced in each of six diverse soybean genotypes. In the …

Characterization Of Bacteriophages Of Pseudomonas Syringae Pv. Tomato, Sara E. Prior, Amanda J. Andrews, Russell O. Nordeen

Journal of the Arkansas Academy of Science

Bacteriophages from supernatants of the plant pathogenic bacteria Pseudomonas syringae pv. tomato (P. tomato) were isolated, enriched, and purified by density block centrifugation in cesium chloride (CsCl) step gradients. The DNA from purified phage was isolated and digested with the restriction endonucleases EcoRl or HindIII. Three different DNA fingerprint patterns were determined indicating 3 unique phage isolates. Genome sizes of the phage ranged from 40 to 52 kilobases (kB). Buoyant densities of phage particles in CsCI varied from 1.36 to 1.51 glml. Electron microscopy revealed a single morphological type with an elongated polyhedral head and a long tail indicating the …

Tungoil Tree (Aleurites Fordii Hemsl.) (Euphorbiaceae): New To The Arkansas Flora, Brett Serviss, Nicole Freeman, Joslyn Hernandez, Allen Leible, Chris Talley

Journal of the Arkansas Academy of Science

No abstract provided.

Genetic Diversity In Populations Of Xanthomonas Campestris Pv. Campestris In Cruciferous Weeds In Central Coastal California, A. Ignatov, A. Sechler, E. L. Schuenzel, I. Agarkova, B. Oliver, A. K. Vidaver, N. W. Schaad

Department of Plant Pathology: Faculty Publications

Xanthomonas campestris pv. campestris (X. campestris) infects a large number of cruciferous plants, including weeds. California has one of the largest and most diverse populations of wild cruciferous plants in the world. Although considerable information is available on the genetic diversity of X. campestris in commercial crop plants, nothing is known about the diversity in strains infecting weeds. To assess the genetic diversity among strains of X. campestris in weeds in noncultivated and cultivated areas, strains of the pathogen were isolated from populations of cruciferous weeds growing in coastal valley crop-production sites and from remote nonproduction sites along the …

Expression Analysis Of Rice Defense-Related Genes In Turfgrass In Response To Magnaporthe Grisea, Young-Ki Jo, Guo-Liang Wang, Michael J. Boehm

Department of Plant Pathology: Faculty Publications

Magnaporthe grisea (anamorph = Pyricularia grisea) causes blast on rice (Oryza sativa) and gray leaf spot on turfgrass. Gray leaf spot is a serious disease on St. Augustinegrass (Stenotaphrum secundatum), perennial ryegrass (Lolium perenne), and tall fescue (Festuca arundinacea). Virulence assays performed in this study revealed that M. grisea collected from rice could also cause disease on St. Augustinegrass and tall fescue. One rice isolate, Che86061, caused similar disease reactions on susceptible cultivars of rice and St. Augustinegrass and an incompatible interaction on resistant cultivars of both species. To explore whether …

Cell Wall Proteome In The Maize Primary Root Elongation Zone. Ii. Region-Specific Changes In Water Soluble And Lightly Ionically Bound Proteins Under Water Deficit1[W][Oa], Jinming Zhu, Sophie Alvarez, Ellen L. Marsh, Mary E. Lenoble, In-Jeong Cho, Mayandi Sivaguru, Sixue Chen, Henry T. Nguyen, Yajun Wu, Daniel P. Schachtman, Robert E. Sharp

Department of Agronomy and Horticulture: Faculty Publications

Previous work on the adaptation of maize (Zea mays) primary roots to water deficit showed that cell elongation is maintained preferentially toward the apex, and that this response involves modification of cell wall extension properties. To gain a comprehensive understanding of how cell wall protein (CWP) composition changes in association with the differential growth responses to water deficit in different regions of the elongation zone, a proteomics approach was used to examine water soluble and loosely ionically bound CWPs. The results revealed major and predominantly region-specific changes in protein profiles between well-watered and water-stressed roots. In total, 152 …

Map Location Of The Rpp1 Locus That Confers Resistance To Soybean Rust In Soybean, D. L. Hyten, G. L. Hartman, R. L. Nelson, R. D. Frederick, V. C. Concibido, J. M. Narvel, P. B. Cregan

Department of Agronomy and Horticulture: Faculty Publications

Soybean rust (SBR), caused by Phakopsora pachyrhizi, was first discovered in North America in 2004 and has the potential to become a major soybean [Glycine max (L.) Merr.] disease in the USA. Currently, four SBR resistance genes have been identifi ed but not mapped on the soybean genetic linkage map. One of these resistance genes is the Rpp1 gene, which is present in the soybean accession PI 200492. The availability of molecular markers associated with Rpp1 will permit marker-assisted selection and expedite the incorporation of this gene into U.S. cultivars. We compared simple sequence repeat (SSR) markers between …

Barcsoysnp23: A Panel Of 23 Selected Snps For Soybean Cultivar Identification, M. S. Yoon, Q.J. Song, I. Y. Choi, James E. Specht, D. L. Hyten, P. B. Cregan

Department of Agronomy and Horticulture: Faculty Publications

This report describes a set of 23 informative SNPs (BARCSoySNP23) distributed on 19 of the 20 soybean linkage groups that can be used for soybean cultivar identification. Selection of the SNPs to include in this set was made based upon the information provided by each SNP for distinguishing a diverse set of soybean genotypes as well as the linkage map position of each SNP. The genotypes included the ancestors of North American cultivars, modern North American cultivars and a group of Korean cultivars. The procedure used to identify this subset of highly informative SNP markers resulted in a significant increase …

Ethylene Involvement In The Regulation Of The H+-Atpase Csha1 Gene And Of The New Isolated Ferric Reductase Csfro1 And Iron Transporter Csirt1 Genes In Cucumber Plants, Brian M. Waters, Carlos Lucena, Francisco J. Romera, Gena G. Jester, April N. Wynn, Carmen L. Rojas, Esteban Alcántara, Rafael Pérez-Vicente

Department of Agronomy and Horticulture: Faculty Publications

In previous works using ethylene inhibitors and precursors, it has been shown that ethylene participates in the regulation of several Fe-deficiency stress responses by Strategy I plants, such as enhanced ferric reductase activity, rhizosphere acidification, and subapical root hair development. Furthermore, recent evidence suggests that ethylene could regulate the expression of both the ferric reductase and the iron transporter genes of Strategy I plants by affecting the FER (or FER-like) transcription factor. Recently, two H⁺-ATPase genes have been isolated from cucumber roots, CsHA1 and CsHA2. CsHA1 is up-regulated under Fe deficiency while CsHA2 is constitutively expressed. In …

Fertility Restoration Of The Sorghum A3 Male-Sterile Cytoplasm Through A Sporophytic Mechanism Derived From Sudangrass, Hoang V. Tang, Jeffrey F. Pedersen, Christine D. Chase, Daryl R. Pring

Department of Agronomy and Horticulture: Faculty Publications

Fertility restoration of sorghum [Sorghum bicolor (L.) Moench] lines carrying the IS1112C (A3 group) male-sterile cytoplasm has been documented as a two-gene gametophytic mechanism involving complementary action of restoring alleles designated Rf3 and Rf4, as derived from IS1112C. Fertility restoration capability has also been reported from sudangrass (S. bicolor subsp. drummondii) populations. We describe characteristics of a fertility restoration system derived from sudangrass, in which male-sterile individuals were observed at high frequency in backcross and F2-F3 segregating populations. Segregation analyses were consistent with a sporophytic restoration system involving two complementary genes. Pollen iodine staining in fertile …

Array-Based Genotyping And Expression Analysis Of Barley Cv. Maythorpe And Golden Promise, Harkamal Walia, Clyde Wilson, Pascal Condamine, Abdelbagi M. Ismail, Jin Xu, Xinping Cui, Timothy J. Close

Department of Agronomy and Horticulture: Faculty Publications

Background: Golden Promise is a salt-tolerant spring barley closely related to Maythorpe. Salt tolerance in Golden Promise has been attributed to a single mutation at the Ari-e locus (on 5H) resulting from irradiation of Maythorpe. Golden Promise accumulates lower shoot Na⁺ compared to Maythorpe when growing under saline conditions. This study focused on elucidating the genetic basis and mechanisms involved in this difference. Results: The level of polymorphism between the two genotypes was explored using the Barley1 GeneChip for single feature polymorphisms (SFPs) and an oligonucleotide pool assay for single nucleotide polymorphisms (SNPs). Polymorphism analyses revealed three haplotype blocks …

Nutrient Use Efficiency: Measurement And Management, Achim Dobermann

Department of Agronomy and Horticulture: Faculty Publications

Mineral fertilizers have sustained world agriculture and thus global population and wealth growth for more than 100 years (Smil, 2001; Stewart et al., 2005). Their contribution to increasing crop yields has spared millions of hectares of natural ecosystems that otherwise would have been converted to agriculture (Balmford et al., 2005). However, lacking, imbalanced, inappropriate or excessive use of nutrients in agricultural systems remains a concern. Nutrient mining is a major cause for low crop yields in parts of the developing world, particularly Africa. In other situations, nutrients such as nitrogen (N) and phosphorus (P) often move beyond the bounds of …

The Effect Of Irrigation On Soil Water Availability And The Plant Water Relations Of Three Species Growing On Revegetated Bauxite Residue Disposal Areas, Sharyn Burgess

Theses : Honours

The waste product resulting from the alumina refining process consists of residue sand and mud which is laid on bauxite residue disposal areas (RDAs). Once the RDAs have been effectively solar dried they are revegetated to minimise deep drainage and potential groundwater contamination. In this study, two RDAs located at Alcoa's Pinjarra refinery were seasonally monitored to determine the effects of irrigation on soil water availability and plant water use. Three experimental Blocks were established by Alcoa, each with an irrigated and unirrigated site. Since then, irrigation has been applied to the three treated sites to maintain the root zone …

2007 Wildflower Of The Year: Atamasco Lily, Zephyranthes Atamasca, W. John Hayden

Biology Faculty Publications

Atamasco lily is a perennial herb that grows from a subterranean bulb. The bulb is dark, with a short neck and papery tunic formed by remnants of old leaf bases. Leaves are glossy green, linear, flat to somewhat concave, up to one half inch wide, approximately one foot in length and, overall, rather grasslike. When not in flower the plants can be easily overlooked. Flowering stems are leafless scapes that are about as long as the leaves. In crosssection the scapes are hollow. Each scape terminates in a single flower. A few papery bracts subtend the flower stalk where it …

Comparison Of Instrumental Methods For Measuring Seed Hardness Of Food-Grade Soybean, Mioko Tamura, Bo Zhang, Joyce Berger-Doyle, Pengyin Chen

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Seed hardness is an important factor in determining soybean suitability for natto production. There is no established methodology for testing seed texture of soybeans. The objective of this study was to develop an efficient method by examining different instruments and seed parameters that could be potentially used for testing soybean seed hardness. Five food-grade soybean genotypes with different seed sizes were used to determine seed hardness and water-absorption capacity. Water absorption capacity was expressed by swell ratios for seed weight, seed dimension, and volume of water changes before and after soaking. Seed hardness test was conducted by a one-bite method …

Varietal Role In The Management Of The Larger Grain Borer, Prostephanus Truncatus (Horn) In Stored Maize, C. P. Rugumamu

Tanzania Journal of Science

The study determined the amount of haemolymph vitellogenin (Vg) of the Larger Grain Borer (LGB), Prostephanus truncatus (Horn) vitellogenic females reared on different maize varieties. The varieties were ZM 521, ZM 421, ECAVL1-DLN, WEEVIL A, LOCAL 1 and LOCAL 2. Sodium Dodecyl Sulphate-Polyacrylamide Gel Electrophoresis (SDS - PAGE) was conducted on the insect haemolymph. F1 LGB adults from each variety were used to determine Indices of Susceptibility (IS) of the varieties to the insect pest attack. Percentages of Vg from female insects and IS were in the order ZM 521>ZM 421> ECAVL1-DLN>WEEVIL A >LOCAL 1>LOCAL 2. Weight …

Vegetation Structure And Heavy Metal Uptake By Plants In The Mining-Impacted And Non Mining-Impacted Sites Of Southern Lake Victoria Wetlands, G. Y. S. Mtui, C. Mligo, M. K. D. Mutakyahwa, J. R. Ikingura

Tanzania Journal of Science

This study assessed the plant species composition and the heavy metal uptake by plants in the mining-impacted and non mining-impacted areas of the southern Lake Victoria basin. The vegetation of the wetlands was stratified into riverine forest, riverine thickets, swampy grassland, open woodland and floodplain grassland. Plant diversity at Nyamtukuza ranged between 2.34 to 2.70; at Geita was 2.29 to 2.57 and Mwakitolyo was between 1.08 to 1.70, which was significantly lower than the other two sites; whereas variation in plant species richness was not significant. TWINSPAN classification resulted into four clusters of the vegetation communities. Cluster A, a shrubby …

Lake Mead National Recreation Area Vegetation Monitoring And Management: Quarterly Progress Report, Period Ending December 31, 2006, Margaret N. Rees

Vegetation Monitoring

Executive Summary

• Two new Weed Sentry research assistants were hired.
• Weed Sentry staff surveyed for exotic species on 89 miles of roads on NPS and BLM land and treated more than 21,000 exotic plants in incipient populations.
• A grid-based rare plant monitoring method was tested this quarter.
• A manuscript detailing vegetation succession on a water pipeline at Lake Mead NRA was submitted for review to the journal Crossosoma.
• New integrative projects undertaken this quarter included establishing a competition study between a native grass and the exotic Sahara mustard, salvaging plants for research purposes from private sites with permission from landowners, …

Evaluating The Performance Of Leucaena Accessions For Agroforestry In Sub-Humid Environment, Southern Tanzania, A. E. Majule

Tanzania Journal of Science

The performance of Leucaena accessions on acid soils in eastern coast Tanzania for agroforestry was evaluated for three years. Plant tree parameters assessed were fodder yield and plant stem height, stem girth, the number of total branches and poles production. Also, Leucaena psyllid, a common pest threatening the plants was also counted. Soil parameters assessed were pH organic carbon, total nitrogen, exchangeable calcium and magnesium. Result showed significant difference in growth between Leucaena accessions. Leucaena leucocephal cv K8 and Leucaena diversifolia were able to grow fast reaching 4.7 and 3.3 m respectively within a period of three years. Leucaena diversifolia …

Spring Ephemeral Plant Diversity As It Relates To Gap Dynamics In Vigo County, Indiana, Jodi K. Farrell Sparks

All-Inclusive List of Electronic Theses and Dissertations

During the course of 25 years, plant specimens from several local locations have been collected and deposited into the Indiana State University (ISU) Herbarium by plant taxonomy students. The locations of some of these plots were reestablished in the spring of 2004. In each plot, all woody and spring herbaceous plants were collected from 26 February 2004 to 12 May 2004. These specimens were identified and compared to previous collections to examine species change in the context of gap dynamics. I compiled a species list for each plot and each preserve. Objectives for this thesis were to document plant diversity …

Nucleic Acids Encoding Pseudomonas Hop Proteins And Use Thereof, Alan Collmer, James R. Alfano, Xiaoyan Tang, C. Robin Buell, Gregory B. Martin

Department of Plant Pathology: Faculty Publications

The present invention relates to isolated nucleic acid molecules encoding a type III—secreted bacterial protein capable of modifying a cell death pathway in a plant cell. One aspect of the present invention involves an isolated nucleic acid molecule having a nucleotide sequence that encodes the HopPtoD2 protein of Pseudomonas syringae pv. syringae DC 3000. Expression vectors, host cells, and transgenic plants which include the DNA molecules of the present invention are also disclosed. The nucleic acid mol ecules of the present invention can be used to impart disease resistance to a plant and to make a plant hypersusceptible to colonization …

Whole-Genome Expression Profiling Defines The Hrpl Regulon Of Pseudomonas Syringae Pv. Tomato Dc3000, Allows De Novo Reconstruction Of The Hrp Cis Element, And Identifies Novel Coregulated Genes, Adriana O. Ferreira, Christopher R. Myers, Jeffrey S. Gordon, Gregory B. Martin, Monica Vencato, Alan Collmer, Misty D. Wehling, James R. Alfano, Gabriel Moreno-Hagelsieb, Warren F. Lamboy, Geneviene Declerck, David J. Schneider, Samuel W. Cartinhour

Department of Plant Pathology: Faculty Publications

Pseudomonas syringae pv. tomato DC3000 is a model pathogen of tomato and Arabidopsis that uses a hypersensitive response and pathogenicity (Hrp) type III secretion system (T3SS) to deliver virulence effector proteins into host cells. Expression of the Hrp system and many effector genes is activated by the HrpL alternative sigma factor. Here, an open reading frame-specific whole-genome microarray was constructed for DC3000 and used to comprehensively identify genes that are differentially expressed in wild-type and ΔhrpL strains. Among the genes whose differential regulation was statistically significant, 119 were upregulated and 76 were downregulated in the wild-type compared with the ΔhrpL …

Microbial Content Of Abattoir Wastewater And Its Contaminated Soil In Lagos, Nigeria, A. O. Adesemoye, B. O. Opere, S. C. O. Makinde

Department of Plant Pathology: Faculty Publications

Microbial content of wastewater in two abattoirs and the impact on microbial population of receiving soil was studied in Agege and Ojo Local Government Areas in Lagos State, Nigeria. Wastewater samples were collected from each of the abattoirs over three months period and examined for microbial content. Soil samples contaminated with the wastewaters were also collected and analyzed for microbial content as compared to soil without wastewater contamination in the neighborhood (control). Some physico-chemical parameters of the samples such as total dissolved solid, chemical oxygen demand, etc., were examined. The wastewater samples from both abattoirs were highly contaminated; Agege abattoir …

Lake Mead National Recreation Area Vegetation Monitoring And Management: Final Close-Out Report, Time Period: October 1, 2005 To September 30, 2006, Margaret N. Rees

Vegetation Monitoring

The National Park Service (NPS) at Lake Mead National Recreation Area (LAME) entered into a cooperative agreement with the University of Nevada, Las Vegas (UNLV) to accomplish vegetation monitoring and management activities. This report summarizes activities that took place by UNLV under this task agreement between October 1, 2005, and September 30, 2006. The activities included:

• Weed Sentry mapping and treating incipient populations of exotic invasive plants throughout Clark County, including along shorelines of Lakes Mead and Mohave;
• Monitoring of targeted rare native plant species;
• Sahara mustard research; and
• Providing technical assistance upon request to the NPS vegetation manager.

In …

Pseudomonas SyringaeHrpj Is A Type Iii Secreted Protein That Is Required For Plant Pathogenesis, Injection Of Effectors,And Secretion Of The Hrpz1 Harpin, Zheng Qing Fu, Ming Guo, James R. Alfano

Center for Plant Science Innovation: Faculty Publications

The bacterial plant pathogen Pseudomonas syringae requires a type III protein secretion system (TTSS) to cause disease. The P. syringae TTSS is encoded by the hrp-hrc gene cluster. One of the genes within this cluster, hrpJ, encodes a protein with weak similarity to YopN, a type III secreted protein from the animal pathogenic Yersinia species. Here, we show that HrpJ is secreted in culture and translocated into plant cells by the P. syringae pv. tomato DC3000 TTSS. A DC3000 hrpJ mutant, UNL140, was greatly reduced in its ability to cause disease symptoms and multiply in Arabidopsis thaliana …

Inducible Yeast System For Viral Rna Recombination Reveals Requirement For An Rna Replication Signal On Both Parental Rnas, Hernan Garcia-Ruiz, Paul Ahlquist

Department of Plant Pathology: Faculty Publications

To facilitate RNA recombination studies, we tested whether Saccharomyces cerevisiae, which supports brome mosaic virus (BMV) replication, also supports BMV RNA recombination. Yeast strains expressing BMV RNA replication proteins 1a and 2a^pol were engineered to transiently coexpress two independently inducible, overlapping, nonreplicating derivatives of BMV genomic RNA3. B33' lacked the coat protein gene and negative-strand RNA promoter. B35' lacked the positive-strand RNA promoter and had the coat gene replaced by the selectable URA3 gene. After 12 to 72 h of induction, B33' and B35' transcription was repressed and Ura⁺ yeast cells were selected. All Ura⁺ cells …