Life Sciences Commons^™

Use Of Cross-Species Amplification Markers For Pollen-Medicated Gene Flow Determination In Trifolium Polymorphum Poiret, M. Dalla Rizza, D. Real, R. Reyno, K. Quesenberry

IGC Proceedings (1997-2023)

The species Trifolium polymorphum Poiret is endemic to Uruguay and is widespread in native grasslands throughout the country. Preliminary observations suggested that the aerial flowers are chasmogamous (open at maturity for potential cross-pollination) while the basal flowers are cleistogamous. Several approaches have been practised to determine the reproductive system of forage legumes by the aid of co-dominant markers (Real et al., 2004; Dalla Rizza et al., 2004). The aim of this study is to explore cross-species amplification as a quick approach to obtain co-dominant markers to study the breeding system of T. polymorphum.

Qtl Analysis And Trait Dissection In Ryegrass (Lolium Spp.), T. Yamada, J. W. Forster

IGC Proceedings (1997-2023)

Key points

1. Molecular marker-based genetic analysis permits the dissection of complex phenotypes through resolution of the locations of pleiotropic and interacting genetic factors.
2. Several QTLs for agronomically important characters such as flowering time, winter hardiness and forage quality have been identified in perennial ryegrass by molecular marker-based map analysis.
3. Some QTLs were putatively orthologous to those for equivalent traits in cereals.
4. The identification of co-location between QTLs and functionally-associated genetic markers is critical for the future implementation of marker-assisted selection programs.

Comparative Genomics And Virulence Studies Of Streptomyces Soil Rot And Scab Pathogen Species, Natasha Soares

LSU Doctoral Dissertations

Comparative genomic analyses were performed to gain insights into the organization and content of the genome of Streptomyces ipomoeae, the soil rot pathogen that infects sweetpotatoes. Unlike Streptomyces scab pathogens, the thaxtomin phytotoxin gene cluster (txt) in S. ipomoeae does not appear to reside within a genomic island and has diverged from its scab pathogen counterparts. Increased usage of the rare TTA codon, particularly for the txt cluster, suggests greater translational control by the bldA tRNA in S. ipomoeae. Orthologous gene searches and secondary metabolite profiling yielded ortholog groups and metabolite gene clusters that were exclusive …

Genetic Characterization Of Antimicrobial Activities Of Endophytic Bacteria Burkholderia Strains Ms455 And Ms389, Jiayuan Jia

Theses and Dissertations

Strains MS455 and MS389, endophytic bacteria, were isolated from healthy soybean plant growing adjacent to a patch of plants affected by charcoal rot disease, caused by the fungal pathogen Macrophomina phaseolina. The complete genomes of both strains were sequenced and identified as Burkholderia species Strain MS455 exhibits broad-spectrum antifungal activities against economically important pathogens, including Aspergillus flavus. Random and site-specific mutations were employed in discovery of the genes that share high homology to the ocf gene cluster of Burkholderia contaminans strain MS14, which is responsible for production of the antifungal compound occidiofungin. RNA-seq analysis demonstrated ORF1, a …

Predicting Transcriptional Responses To Cold Stress Across Plant Species, Xiaoxi Meng, Zhikai Liang, Xiuru Dai, Yang Zhang, Samira Mahboub, Daniel W. Ngu, Rebecca Roston, James Schnable

Center for Plant Science Innovation: Faculty and Staff Publications

Although genome-sequence assemblies are available for a growing number of plant species, gene-expression responses to stimuli have been cataloged for only a subset of these species. Many genes show altered transcription patterns in response to abiotic stresses. However, orthologous genes in related species often exhibit different responses to a given stress. Accordingly, data on the regulation of gene expression in one species are not reliable predictors of orthologous gene responses in a related species. Here, we trained a supervised classification model to identify genes that transcriptionally respond to cold stress. A model trained with only features calculated directly from genome …

A Comparative Genome Analysis Of Cercospora Sojina With Other Members Of The Pathogen Genus Mycosphaerella On Different Plant Hosts, Fanchang Zeng, Xin Lian, Guirong Zhang, Xiaoman Yu, Carl A. Bradley, Ray Ming

Plant Pathology Faculty Publications

Fungi are the causal agents of many of the world's most serious plant diseases causing disastrous consequences for large-scale agricultural production. Pathogenicity genomic basis is complex in fungi as multicellular eukaryotic pathogens. Here, we report the genome sequence of C. sojina, and comparative genome analysis with plant pathogen members of the genus Mycosphaerella (Zymoseptoria. tritici (synonyms M. graminicola), M. pini, M. populorum and M. fijiensis - pathogens of wheat, pine, poplar and banana, respectively). Synteny or collinearity was limited between genomes of major Mycosphaerella pathogens. Comparative analysis with these related pathogen genomes indicated distinct genome-wide repeat …

Swainsonine Biosynthesis Genes In Diverse Symbiotic And Pathogenic Fungi, Daniel Cook, Bruno G. G. Donzelli, Rebecca Creamer, Deana L. Baucom, Dale R. Gardner, Juan Pan, Neil Moore, Stuart B. Krasnoff, Jerzy W. Jaromczyk, Christopher L. Schardl

Plant Pathology Faculty Publications

Swainsonine—a cytotoxic fungal alkaloid and a potential cancer therapy drug—is produced by the insect pathogen and plant symbiont Metarhizium robertsii, the clover pathogen Slafractonia leguminicola, locoweed symbionts belonging to Alternaria sect. Undifilum, and a recently discovered morning glory symbiont belonging to order Chaetothyriales. Genome sequence analyses revealed that these fungi share orthologous gene clusters, designated “SWN,” which included a multifunctional swnKgene comprising predicted adenylylation and acyltransferase domains with their associated thiolation domains, a β-ketoacyl synthase domain, and two reductase domains. The role of swnK was demonstrated by inactivating it in M. robertsii through homologous …