Characterization of Caulimovirid-like Sequences from Upland Cotton ( L.) Exhibiting Terminal Abortion in Georgia, USA.

In this study, we investigated the potential involvement of endogenous viral elements (EVEs) in the development of apical tissue necrosis, resulting in the terminal abortion of upland cotton ( L.) in Georgia. The high-throughput sequence analysis of symptomatic and asymptomatic plant tissue samples revealed near-complete EVE-Georgia (EVE-GA) sequences closely related to caulimoviruses.

An analysis of lncRNAs related to fiber quality and the discovery of their target genes in a Gossypium hirsutum line with Gossypium mustelinum introgression.

Analysis of fiber quality lncRNAs and their target genes from a pair of Gossypium mustelinum near-isogenic lines provide new prospects for improving the fiber quality of Upland cotton. Long noncoding RNAs (lncRNAs) are an important part of genome transcription and play roles in a wide range of biological processes in plants. In this research, a pair of near-isogenic cotton lines, namely, a Gossypium mustelinum introgression line (IL9) with outstanding fiber quality and its recurrent Upland cotton parent (PD94042), were used as the experimental materials.

Cotton leafroll dwarf disease: An enigmatic viral disease in cotton.

Taxonomy: Cotton leafroll dwarf virus (CLRDV) is a member of the genus Polerovirus, family Solemoviridae. Geographical Distribution: CLRDV is present in most cotton-producing regions worldwide, prominently in North and South America.

Physical Properties: The virion is a nonenveloped icosahedron with T = 3 icosahedral lattice symmetry that has a diameter of 26-34 nm and comprises 180 molecules of the capsid protein.

Identification of small effect quantitative trait loci of plant architectural, flowering, and early maturity traits in reciprocal interspecific introgression population in cotton.

Plant architecture, flowering time and maturity traits are important determinants of yield and fiber quality of cotton. Genetic dissection of loci determining these yield and quality components is complicated by numerous loci with alleles conferring small differences. Therefore, mapping populations segregating for smaller numbers and sizes of introgressed segments is expected to facilitate dissection of these complex quantitative traits.

Improved Upland Cotton Germplasm for Multiple Fiber Traits Mediated by Transferring and Pyramiding Novel Alleles From Ethyl Methanesulfonate-Generated Mutant Lines Into Elite Genotypes.

Ethyl methanesulfonate (EMS) mutagenesis offers important advantages for improving crops, such as cotton, with limited diversity in elite gene pools. EMS-induced point mutations are less frequently associated with deleterious traits than alleles from wild or exotic germplasm. From 157 mutant lines that have significantly improved fiber properties, we focused on nine mutant lines here.

Effect of Cotton Leafroll Dwarf Virus on Physiological Processes and Yield of Individual Cotton Plants.

Cotton leafroll dwarf disease (CLRDD) caused by cotton leafroll dwarf virus (CLRDV) is an emerging threat to cotton production in the United States. The disease was first reported in Alabama in 2017 and subsequently has been reported in 10 other cotton producing states in the United States, including Georgia. A field study was conducted at field sites near Tifton, Georgia in 2019 and 2020 to evaluate leaf gas exchange, chlorophyll fluorescence, and leaf temperature responses for a symptomatic cultivar (diseased plants observed at regular frequency) at multiple stages of disease progression and for asymptomatic cultivars (0% disease incidence observed).

Transcriptome analysis reveals genes potentially related to high fiber strength in a line IL9 with introgression.

Cotton ( L.) is the most important fiber crop worldwide. Here, transcriptome analysis was conducted on developing fibers of a introgression line, IL9, and its recurrent parent, PD94042, at 17 and 21 days post-anthesis (dpa).

Genome analysis of cotton leafroll dwarf virus reveals variability in the silencing suppressor protein, genotypes and genomic recombinants in the USA.

Cotton leafroll dwarf virus (CLRDV) is an emerging virus in cotton production in Georgia and several other Southeastern states in the USA. To better understand the genetic diversity of the virus population, the near complete genome sequences of six isolates from Georgia and one from Alabama were determined. The isolates sequenced were 5,866 nucleotides with seven open reading frames (ORFs).

The effect of two QTLs for resistance to in cotton on nematode egression from roots.

Cotton is widely grown in the southern US and is its most significant pathogen. The germplasm line M-120 RNR is highly resistant to due to two resistance QTLs (quantitative trait loci), and . Both QTLs reduce total egg production, but the QTLs affect development at different life stages.

Validation of QTLs for Fiber Quality Introgressed from by Selective Genotyping.

Gene introgression from wild species has been shown to be a feasible approach for fiber quality improvement in Upland cotton. Previously, we developed an interspecific × advanced-backcross population and mapped over one hundred QTL for fiber quality traits. In the current study, a trait-based selective genotyping approach was utilized to prioritize a small subset of introgression lines with high phenotypic values for different fiber quality traits, to simultaneously validate multiple fiber quality QTL in a single experiment.

Transcriptome analysis of a nematode resistant and susceptible upland cotton line at two critical stages of Meloidogyne incognita infection and development.

Host plant resistance is the most practical approach to control the Southern root-knot nematode (Meloidogyne incognita; RKN), which has emerged as one of the most serious economic pests of Upland cotton (Gossypium hirsutum L.). Previous QTL analyses have identified a resistance locus on chromosome 11 (qMi-C11) affecting galling and another locus on chromosome-14 (qMi-C14) affecting egg production.

Major QTLs for Resistance to Early and Late Leaf Spot Diseases Are Identified on Chromosomes 3 and 5 in Peanut ().

Early and late leaf spots (LLSs) are the major foliar diseases of peanut responsible for severely decreased yield in the absence of intensive fungicide spray programs. Pyramiding host resistance to leaf spots in elite cultivars is a sustainable solution to mitigate the diseases. In order to determine the genetic control of leaf spot disease resistance in peanut, a recombinant inbred line population (Florida-07 × GP-NC WS16) segregating for resistance to both diseases was used to construct a SNP-based linkage map consisting of 855 loci.

Fusarium wilt of cotton may commonly result from the interaction of f. sp. with .

The interaction between f. sp. (Fov) and (root-knot nematode) resulting in Fusarium wilt (FW) of cotton is well-known.

Resistance Quantitative Trait Loci and in Cotton Have Different Effects on the Development of , the Southern Root-Knot Nematode.

Quantitative trait loci (QTLs) and impart a high level of resistance to in cotton. Breeders had previously backcrossed both QTLs into the susceptible Coker 201 to create the highly resistant M-120 RNR, and we crossed Coker 201 and M-120 RNR to create near-isogenic lines with either or . Previous work suggests different modes of action for and .

In-field High Throughput Phenotyping and Cotton Plant Growth Analysis Using LiDAR.

Plant breeding programs and a wide range of plant science applications would greatly benefit from the development of in-field high throughput phenotyping technologies. In this study, a terrestrial LiDAR-based high throughput phenotyping system was developed. A 2D LiDAR was applied to scan plants from overhead in the field, and an RTK-GPS was used to provide spatial coordinates.

Advanced Backcross QTL Analysis of Fiber Strength and Fineness in a Cross between and .

The molecular genetic basis of cotton fiber strength and fineness in crosses between and (Upland cotton) was dissected using 21 BCF and 12 corresponding BCF and BCF families. The BCF families were genotyped with simple sequence repeat markers from a by linkage map, and the three generations of BC-derived families were phenotyped for fiber strength (STR) and fineness (Micronaire, MIC). A total of 42 quantitative trait loci (QTLs) were identified through one-way analysis of variance, including 15 QTLs for STR and 27 for MIC, with the percentage of variance explained by individual loci averaging 13.

Segregation distortion and genome-wide digenic interactions affect transmission of introgressed chromatin from wild cotton species.

This study reports transmission genetics of chromosomal segments into Gossypium hirsutum from its most distant euploid relative, Gossypium mustelinum . Mutilocus interactions and structural rearrangements affect introgression and segregation of donor chromatin. Wild allotetraploid relatives of cotton are a rich source of genetic diversity that can be used in genetic improvement, but linkage drag and non-Mendelian transmission genetics are prevalent in interspecific crosses.

Identification and Characterization of miRNA Transcriptome in Asiatic Cotton () Using High Throughput Sequencing.

MicroRNAs (miRNAs) are small 20-24nt molecules that have been well studied over the past decade due to their important regulatory roles in different cellular processes. The mature sequences are more conserved across vast phylogenetic scales than their precursors and some are conserved within entire kingdoms, hence, their loci and function can be predicted by homology searches. Different studies have been performed to elucidate miRNAs using prediction methods but due to complex regulatory mechanisms or false positive predictions, not all of them express in reality and sometimes computationally predicted mature transcripts differ from the actual expressed ones.

Fine mapping and candidate gene analysis of qFL-chr1, a fiber length QTL in cotton.

A fiber length QTL, qFL-chr1, was fine mapped to a 0.9 cM interval of cotton chromosome 1. Two positional candidate genes showed positive correlation between gene expression level and fiber length.

QTL analysis of cotton fiber length in advanced backcross populations derived from a cross between Gossypium hirsutum and G. mustelinum.

QTLs for fiber length mapped in three generations of advanced backcross populations derived from crossing Gossypium hirsutum and Gossypium mustelinum showed opportunities to improve elite cottons by introgression from wild relatives. The molecular basis of cotton fiber length in crosses between Gossypium hirsutum and Gossypium mustelinum was dissected using 21 BCF and 12 corresponding BCF and BCF families. Sixty-five quantitative trait loci (QTLs) were detected by one-way analysis of variance.

Fine mapping and identification of candidate genes for a QTL affecting Meloidogyne incognita reproduction in Upland cotton.

Background: The southern root-knot nematode (Meloidogyne incognita; RKN) is one of the most important economic pests of Upland cotton (Gossypium hirsutum L.). Host plant resistance, the ability of a plant to suppress nematode reproduction, is the most economical, practical, and environmentally sound method to provide protection against this subterranean pest.

A Genetic Map Between Gossypium hirsutum and the Brazilian Endemic G. mustelinum and Its Application to QTL Mapping.

Among the seven tetraploid cotton species, little is known about transmission genetics and genome organization in Gossypium mustelinum, the species most distant from the source of most cultivated cotton, G. hirsutum In this research, an F2 population was developed from an interspecific cross between G. hirsutum and G.

Comparative transmission genetics of introgressed chromatin in Gossypium (cotton) polyploids.

Premise Of The Study: Introgression is widely acknowledged as a potential source of valuable genetic variation, and growing effort is being invested in analysis of interspecific crosses conferring transgressive variation. Experimental backcross populations provide an opportunity to study transmission genetics following interspecific hybridization, identifying opportunities and constraints to introgressive crop improvement. The evolutionary consequences of introgression have been addressed at the theoretical level, however, issues related to levels and patterns of introgression among (plant) species remain inadequately explored, including such factors as polyploidization, subgenome interaction inhabiting a common nucleus, and the genomic distribution and linkage relationships of introgressant alleles.