scholarly journals Segregation of Flower Color and Eyespot in Althea

2020 ◽  
Vol 145 (4) ◽  
pp. 215-227
Author(s):  
Jason D. Lattier ◽  
Ryan N. Contreras
Keyword(s):  
Single Gene ◽  
Flower Color ◽  
Recessive Allele ◽  
Body Color ◽  
Dominant Group ◽  
Full Color ◽  
Plant Data ◽  
Low Levels ◽  
Ornamental Shrub ◽  
Dark Pink

Althea (Hibiscus syriacus) is an ornamental shrub prized for its winterhardiness, flower colors, and unique flower forms, including single-flowered and double-flowered types. Although floral traits are most important for breeders of althea, little is known about their segregation patterns. The objective of this study was to determine segregation patterns in flower color, including eyespot, among hybrid seedlings of elite taxa. Over 4 years, more than 3100 flowering seedlings were produced for observation of F1, F2, and backcross families. For each plant, data were collected including presence of eyespot and petal body color (CIEL*a*b*) using a colorimeter. Recessive testcrosses and χ2 analyses were performed among three taxa (‘Buddha Belly’, ‘Diana’, and White Chiffon®), and between this recessive group and a suite of colorful taxa. Self-pollination and intercrosses within homozygous dominant and homozygous recessive groups further confirmed their genotypes. Based on these results, we propose that eyespot is controlled by a single gene called spotless, named for the recessive allele that results in a complete elimination of color in flowers. Crosses that resulted in seedlings that all produced eyespots were observed to segregate for color in the petal body. Of these, one group produced white to blush pink petals, which was recessive to full color. Recessive testcrosses and χ2 analyses were performed among nine taxa exhibiting eyespots with white to blush petal bodies, and between taxa with full-color petal bodies. These testcrosses resulted in a putative homozygous dominant group composed mostly of blue and dark pink taxa, whereas the heterozygous group was composed mostly of pink taxa. Spotless taxa were also added to these two groups, suggesting an epistatic interaction with the spotless allele. Based on these results, we propose that petal body color is controlled by a single gene called geisha, named for the recessive allele that produces white to blush-pink petal bodies and dark red eyespot. This trait exhibits incomplete dominance and is under epistatic control by spotless. Geisha-type flowers lack pigment in the petal body, or exhibit a blush pink, likely produced by low levels of cyanidin, peonidin, and pelargonidin. The interaction and segregation of these two genes was confirmed in F1, F2, and backcross families from two crosses: Lil’ Kim™ × Blue Chiffon™ and Fiji™ × White Chiffon®. This study on segregation of flower color in H. syriacus contributes substantial and useful information on inheritance of color and will facilitate targeted breeding to improve this vibrant ornamental shrub.

Low effluent nutrient technologies for wastewater treatment

2006 ◽  
Vol 53 (3) ◽  
pp. 165-172 ◽  
Author(s):  
K.R. Pagilla ◽  
M. Urgun-Demirtas ◽  
R. Ramani
Keyword(s):  
Wastewater Treatment ◽  
Wastewater Treatment Plants ◽  
P Uptake ◽  
Organic N ◽  
Total N ◽  
Technology Gaps ◽  
Plant Data ◽  
Low Levels ◽  
Chemical Usage ◽  
Total P

The USEPA (2001) water quality nutrient criteria will have a significant impact on water pollution control industry due to stringent N and P requirements. This paper presents an update of findings on successful total N (TN) and total P (TP) technologies being implemented at existing wastewater treatment plants (WWTP) to achieve low TN and TP effluents and some key challenges in achieving lower levels. Plants consistently achieving <5 mg TN/L and <0.5 mg TP/L were identified from a worldwide literature search and plant data collection. Technology gaps and research needs to improve successful technologies to achieve very low TN and TP effluents are summarised in this paper. The dissolved and colloidal organic N have been identified as major challenges in achieving very low levels of TN. Technical and economic challenges to achieve very low TP effluents include alkalinity deficiency, high chemical usage, high sludge production and lack of sufficient influent BOD for biological P uptake.

Host species specificity of the goldenrod rust fungus and the existence of rust resistance within some goldenrod species

1992 ◽  
Vol 70 (12) ◽  
pp. 2461-2466 ◽  
Author(s):  
Michèle C. Heath
Keyword(s):  
British Columbia ◽  
Rust Resistance ◽  
Selective Pressure ◽  
Specific Resistance ◽  
Rust Fungus ◽  
Single Gene ◽  
Rust Fungi ◽  
Nonhost Resistance ◽  
Low Levels ◽  
Coleosporium Asterum

Five out of six species of goldenrod at a study site in Ontario had rust pustules in the field and also developed pustules after laboratory inoculation with urediospores of a single-pustule isolate of the rust fungus (Coleosporium asterum) obtained from Solidago canadensis. This isolate also successfully infected seedlings of S. canadensis and an additional goldenrod species from British Columbia. Light microscopy revealed low levels of spore germination and high levels of failed infection attempts even on susceptible plants; in S. canadensis, infection commonly failed before the formation of the first haustorium, a phenomenon typical of nonhost resistance and indicative of a degree of nonspecific incompatibility between fungus and host. Only 2 out of over 200 S. canadensis seedlings from Ontario or British Columbia lacked pustules after repeated inoculations compared with 7 out of 36 for Solidago rugosa seedlings from the study site. Microscopically, infection sites in most of these resistant plants resembled those in crop plants with parasite-specific, single-gene resistance. The data raise the possibility that the fungus has exerted a stronger selective pressure for parasite-specific resistance on S. rugosa than on S. canadensis. Key words: Coleosporium asterum, goldenrod, rust fungi, Solidago, specificity.

scholarly journals Identification of a BTV-Strain-Specific Single Gene That Increases Culicoides Vector Infection Rate

Viruses ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1781
Author(s):  
Honorata M. Ropiak ◽  
Simon King ◽  
Marc Guimerà Busquets ◽  
Kerry Newbrook ◽  
Gillian D. Pullinger ◽  
...  
Keyword(s):  
Infection Rate ◽  
Bluetongue Virus ◽  
Genetic Basis ◽  
Single Gene ◽  
Field Strain ◽  
Economic Losses ◽  
Amino Acid Substitutions ◽  
Low Levels ◽  
Culicoides Vectors ◽  
Virus Strains

Since the 2000s, the distribution of bluetongue virus (BTV) has changed, leading to numerous epidemics and economic losses in Europe. Previously, we found a BTV-4 field strain with a higher infection rate of a Culicoides vector than a BTV-1 field strain has. We reverse-engineered parental BTV-1 and BTV-4 strains and created BTV-1/BTV-4 reassortants to elucidate the influence of individual BTV segments on BTV replication in both C. sonorensis midges and in KC cells. Substitution of segment 2 (Seg-2) with Seg-2 from the rBTV-4 significantly increased vector infection rate in reassortant BTV-14S2 (30.4%) in comparison to reverse-engineered rBTV-1 (1.0%). Replacement of Seg-2, Seg-6 and Seg-7 with those from rBTV-1 in reassortant BTV-41S2S6S7 (2.9%) decreased vector infection rate in comparison to rBTV-4 (30.2%). However, triple-reassorted BTV-14S2S6S7 only replicated to comparatively low levels (3.0%), despite containing Seg-2, Seg-6 and Seg-7 from rBTV-4, indicating that vector infection rate is influenced by interactions of multiple segments and/or host-mediated amino acid substitutions within segments. Overall, these results demonstrated that we could utilize reverse-engineered viruses to identify the genetic basis influencing BTV replication within Culicoides vectors. However, BTV replication dynamics in KC cells were not suitable for predicting the replication ability of these virus strains in Culicoides midges.

scholarly journals The Global Transcriptional Response of Bacillus subtilis to Peroxide Stress Is Coordinated by Three Transcription Factors

2003 ◽  
Vol 185 (1) ◽  
pp. 243-253 ◽  
Author(s):  
John D. Helmann ◽  
Ming Fang Winston Wu ◽  
Ahmed Gaballa ◽  
Phil A. Kobel ◽  
Maud M. Morshedi ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Transcription Factors ◽  
Transcriptional Profiling ◽  
Single Gene ◽  
Transcriptional Response ◽  
Butyl Alcohol ◽  
Complex Adaptive ◽  
Butyl Peroxide ◽  
Low Levels ◽  
Kinetics Of

ABSTRACT Bacillus subtilis exhibits a complex adaptive response to low levels of peroxides. We used global transcriptional profiling to monitor the magnitude and kinetics of changes in the mRNA population after exposure to either hydrogen peroxide (H2O2) or tert-butyl peroxide (t-buOOH). The peroxide stimulons could be largely accounted for by three regulons controlled by the PerR, σB, and OhrR transcription factors. Three members of the PerR regulon (katA, mrgA, and zosA) were strongly induced by H2O2 and weakly induced by t-buOOH. The remaining members of the PerR regulon were only modestly up-regulated by peroxide treatment. Overall, the magnitude of peroxide induction of PerR regulon genes corresponded well with the extent of derepression in a perR mutant strain. The σB regulon was activated by 58 μM H2O2 but not by 8 μM H2O2 and was strongly activated by either t-buOOH or, in a control experiment, tert-butyl alcohol. Apart from the σB regulon there was a single gene, ohrA, that was strongly and rapidly induced by t-buOOH exposure. This gene, controlled by the peroxide-sensing repressor OhrR, was not induced by any of the other conditions tested.

scholarly journals AFLP and SSR markers linked to the yellow seed colour gene in Brassica juncea L.

2011 ◽  
Vol 47 (No. 4) ◽  
pp. 149-155
Author(s):  
Z. Huang ◽  
Y. Zhang ◽  
H.Q. Li ◽  
L. Yang ◽  
Y.Y. Ban ◽  
...  
Keyword(s):  
Brassica Juncea ◽  
Ssr Markers ◽  
Single Gene ◽  
Recessive Allele ◽  
Erucic Acid Content ◽  
Sequence Information ◽  
Seed Colour ◽  
Yellow Seed ◽  
Yellow Mustard ◽  
Colour Gene

Yellow mustard, cultivated in northern Shaanxi of China, is a valuable germplasm of Brassica juncea with low erucic acid content. Its yellow seed colour is controlled by a recessive allele of a single gene, whose dominant allele conditions brown seed colour. To map the yellow seed colour allele, amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) technologies were used to identify markers linked to the recessive allele. The analysis was done on 386 F<sub>2</sub> plants, segregating for seed colour, from the cross Wuqi yellow mustard &times; Wugong mustard. The plants were selfed to determine their seed colour genotype. Twenty AFLP markers and eight SSR markers were identified from 256 AFLP primer combinations and 624 pairs of SSR primers, respectively. Blast analysis indicated that the sequences of four closely linked AFLP and SSR markers showed good collinearity with those of Arabidopsis chromosome 3, and the homologue of the yellow seed colour allele was located between At3g14190 and At3g32130. Sequence information of the region between the two genes of Arabidopsis could be used to develop more closely linked markers to narrow down the homologue of the yellow seed colour allele. These results would accelerate the procedure of yellow seed colour gene cloning and marker-assisted selection for yellow mustard.&nbsp;

Cloning of the Pleiotropic T Locus in Soybean and Two Recessive Alleles That Differentially Affect Structure and Expression of the Encoded Flavonoid 3′ Hydroxylase

Genetics ◽  
2003 ◽  
Vol 163 (1) ◽  
pp. 295-309
Author(s):  
Gracia Zabala ◽  
Lila Vodkin
Keyword(s):  
Frameshift Mutation ◽  
Flower Color ◽  
Flavonoid Pathway ◽  
Genetic Stock ◽  
Color Mutant ◽  
H Gene ◽  
Low Levels ◽  
Mutant Lines ◽  
Seed Coats ◽  
T Locus

Abstract Three loci (I, R, and T) control pigmentation of the seed coats in Glycine max and are genetically distinct from those controlling flower color. The T locus also controls color of the trichome hairs. We report the identification and isolation of a flavonoid 3′ hydroxylase gene from G. max (GmF3′H) and the linkage of this gene to the T locus. This GmF3′H gene was highly expressed in early stages of seed coat development and was expressed at very low levels or not at all in other tissues. Evidence that the GmF3′H gene is linked to the T locus came from the occurrence of multiple RFLPs in lines with varying alleles of the T locus, as well as in a population of plants segregating at that locus. GmF3′H genomic and cDNA sequence analysis of color mutant lines with varying t alleles revealed a frameshift mutation in one of the alleles. In another line derived from a mutable genetic stock, the abundance of the mRNAs for GmF3′H was dramatically reduced. Isolation of the GmF3′H gene and its identification as the T locus will enable investigation of the pleiotropic effects of the T locus on cell wall integrity and its involvement in the regulation of the multiple branches of the flavonoid pathway in soybean.

scholarly journals GENETICS OF FERTILITY RESTORATION IN THE C-GROUP OF CYTOPLASMIC MALE STERILITY IN MAIZE

Genetics ◽  
1981 ◽  
Vol 98 (2) ◽  
pp. 379-388
Author(s):  
A Kheyr-Pour ◽  
V E Gracen ◽  
H L Everett
Keyword(s):  
Cytoplasmic Male Sterility ◽  
Male Sterility ◽  
Comparative Studies ◽  
Pollen Fertility ◽  
Fertility Restoration ◽  
Single Gene ◽  
Rf Gene ◽  
Allelism Tests ◽  
Low Levels

ABSTRACT The genetics of fertility restoration of cms-C group cytoplasm of maize was studied using crosses involving stable maintainer lines and lines that restored full pollen fertility. Pollen fertility in the sources of cms-C sterile cytoplasms studied was restored by a single dominant restorer (Rf4) gene. The fertility restoration was sporophytic. Allelism tests among five restorer lines showed that they all apparently carried the same alleles (Rf4 Rf4). Similar tests also demonstrated that seven nonrestoring maintainer lines had apparently the same genotype (rf4 rf4), although a partial "late break" of fertility was observed at low levels in some maintainer crosses. Comparative studies among different cms-C sources (C, Bb, ES, PR and RB) indicated that similar inheritance of fertility restoration was involved. The data indicated that a single, dominant Rf gene is involved in the restoration of several C-group cytoplasms, at least in the lines studied here. This is the first single-gene, sporophytic restorer system described in maize to date.

Yield and seasonal growth flushing of Protea 'Pink Ice' and Leucadendron 'Silvan Red' in South Australia

1996 ◽  
Vol 36 (7) ◽  
pp. 869 ◽  
Author(s):  
GE Barth ◽  
NA Maier ◽  
JS Cecil ◽  
WL Chyvl ◽  
MN Bartetzko
Keyword(s):  
Growth Rate ◽  
Stem Elongation ◽  
South Australia ◽  
Annual Growth ◽  
Stem Length ◽  
Seasonal Growth ◽  
Fertile Soil ◽  
Plant Data ◽  
Low Levels

Data on yield and growth flushing of 2 protea varieties were collected at commercial sites in South Australia over 3 years. Mean (� s.e.) yield of Protea 'Pink Ice' in terms of marketable stems averaged 63 (�) stems/plant on a highly fertile soil to 39 (�1) stemslplant on an infertile site. On the same sites, Leucadendron 'Silvan Red' yielded means (�se.) of 314 (�13) and 219 (�5) marketable stems/plant. Data are presented in marketing classes based on stem length. Monthly increases in stem length and diameter were used to determine seasonal growth flushing patterns in the 2 cultivars. Pink Ice commenced annual growth in August-September, reached peak growth rate in October and fell to low levels in December. Silvan Red commenced growth between October and November, reached peak growth rate in December and continued stem elongation until March when all growth ceased until the following year.

scholarly journals Predicting insecticide resistance: mutagenesis, selection and response

1998 ◽  
Vol 353 (1376) ◽  
pp. 1729-1734 ◽  
Author(s):  
J. A. McKenzie ◽  
P. Batterham
Keyword(s):  
Single Gene ◽  
Natural Populations ◽  
Selective Advantage ◽  
Resistance Mechanisms ◽  
Predictive Capacity ◽  
Evolution Of Resistance ◽  
Australian Sheep ◽  
Delivery Strategies ◽  
Low Levels ◽  
Molecular Bases

Strategies to manage resistance to a particular insecticide have usually been devised after resistance has evolved. If it were possible to predict likely resistance mechanisms to novel insecticides before they evolved in the field, it might be feasible to have programmes that manage susceptibility. With this approach in mind, single–gene variants of the Australian sheep blowfly, Lucilia cuprina , resistant to dieldrin, diazinon and malathion, were selected in the laboratory after mutagenesis of susceptible strains. The genetic and molecular bases of resistance in these variants were identical to those that had previously evolved in natural populations. Given this predictive capacity for known resistances, the approach was extended to anticipate possible mechanisms of resistance to cyromazine, an insecticide to which L. cuprina populations remain susceptible after almost 20 years of exposure. Analysis of the laboratory–generated resistant variants provides an explanation for this observation. The variants show low levels of resistance and a selective advantage over susceptibles for only a limited concentration range. These results are discussed in the context of the choice of insecticides for control purposes and of delivery strategies to minimize the evolution of resistance.

scholarly journals GENETIC CONTROL OF QUANTITATIVE VARIATION IN SELF-INCOMPATIBILITY PROTEINS DETECTED BY IMMUNODIFFUSION

Genetics ◽  
1974 ◽  
Vol 76 (1) ◽  
pp. 45-50
Author(s):  
M E Nasrallah
Keyword(s):  
Genetic Control ◽  
Genetic Basis ◽  
Seed Set ◽  
Single Gene ◽  
Inbred Lines ◽  
The Self ◽  
Self Incompatibility ◽  
Dosage Effects ◽  
Low Levels ◽  
S Proteins

ABSTRACT Single radial immunodiffusion was used to study the self-incompatibility (S) proteins present in stigmas of two inbred lines of Brassica oleracea: a self-incompatible line and a self-compatible mutant derived from it. The genetic basis of observed quantitative differences in S proteins between the two inbreds was shown to be determined by a single gene with dosage effects. Self-pollination of individual plants with high, intermediate and low levels of S protein in the stigmas, respectively, resulted in low, intermediate and high seed set.

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