Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network

Open Access. Powered by Scholars. Published by Universities.®

PDF

Plant Sciences

Theses/Dissertations

Louisiana State University

Sweetpotato

Articles 1 - 4 of 4

Full-Text Articles in Entire DC Network

Identification Of Blda As A Major Regulator Of Virulence In The Sweetpotato Soil Rot Pathogen Streptomyces Ipomoeae And Characterization Of Distinct Clostridium Sweetpotato Soft Rot Isolates, Kuei-Ting Yang Dec 2020

Identification Of Blda As A Major Regulator Of Virulence In The Sweetpotato Soil Rot Pathogen Streptomyces Ipomoeae And Characterization Of Distinct Clostridium Sweetpotato Soft Rot Isolates, Kuei-Ting Yang

LSU Doctoral Dissertations

Streptomyces ipomoeae is the causative agent of Streptomyces soil rot on sweetpotato, a disease characterized by extensive necrosis of both adventitious and storage roots. While Streptomyces potato scab pathogens produce a phytotoxin (thaxtomin A), which is induced in the presence of cellobiose and suberin, S. ipomoeae produces a less-modified, phytotoxin (thaxtomin C), whose inducer has not been identified. To investigate transcriptional regulation of thaxtomin C production, we inserted a promoter involved in thaxtomin C synthesis upstream of the gusA reporter in an S. ipomoeae strain. Reporter gene expression was significantly upregulated in the presence of size-fractionated sweetpotato extract (SPE). The …


Sweetpotato Virus C And Its Contribution To The Potyvirus Complex In Sweetpotato (Ipomoea Batatas), Favio E. Herrera Eguez Nov 2017

Sweetpotato Virus C And Its Contribution To The Potyvirus Complex In Sweetpotato (Ipomoea Batatas), Favio E. Herrera Eguez

LSU Doctoral Dissertations

In Louisiana, sweetpotato (Ipomoea batatas) is infected in Louisiana by the four ubiquitous potyviruses: Sweetpotato feathery mottle virus (SPFMV), Sweetpotato virus G (SPVG), Sweetpotato virus 2 (SPV2) and the strain of SPFMV previously known as the common strain, recently renamed as Sweetpotato virus C (SPVC). These four viruses belong to the Potyviridae family, with single stranded RNA of ~11kb. In this group of plant viruses, a single polyprotein is coded entirely but later cleaved into ten mature proteins: P1, HC-pro, P3, 6K1, CI, 6K2, NIa-VPg, NIa-Pro Nib and Coat Protein (CP). In sweetpotato potyviruses, two additional open reading …


Sweetpotato Storage Root Rots: Flooding-Associated Bacterial Soft Rot Caused By Clostridium Spp. And Infection By Fungal End Rot Pathogens Prior To Harvest, Washington Luis Da Silva Jan 2013

Sweetpotato Storage Root Rots: Flooding-Associated Bacterial Soft Rot Caused By Clostridium Spp. And Infection By Fungal End Rot Pathogens Prior To Harvest, Washington Luis Da Silva

LSU Master's Theses

Sweetpotato production in the southern United States is being threatened by a soft rot that develops in storage roots when fields are flooded and by an important post-harvest disease caused mainly by the fungi Fusarium solani and Macrophomina phaseolina. To identify the pathogens responsible for development of the soft rot, samples were collected from storage roots with soft rot from intentionally flooded fields and decayed tissue was streaked on plates of nutrient dextrose agar plus 0.05% cysteine and incubated anaerobically. Two distinct groups of Gram positive strict anaerobic bacteria were re-isolated from rotting storage roots. Endospores were observed in all …


Molecular Diversity And Coat Protein Expression Of Sweet Potato Leaf Curl Virus, Dina Lida Gutierrez Reynoso Jan 2008

Molecular Diversity And Coat Protein Expression Of Sweet Potato Leaf Curl Virus, Dina Lida Gutierrez Reynoso

LSU Doctoral Dissertations

Leaf curl virus diseases have been reported in sweetpotato throughout the world. One of the causal agents is Sweet potato leaf curl virus (SPLCV) which belongs to the genus Begomovirus (family Geminiviridae). In the United States, SPLCV has been found infecting an ornamental sweetpotato and several breeding lines but not in sweetpotatoes grown for commercial production. SPLCV does not cause symptoms on Beauregard, the predominant sweetpotato cultivar in the US, but it can reduce its yield. Since SPLCV could become an important constraint for sweetpotato production; diagnosis, identification, and characterization are essential steps to develop an effective management program. The …