scholarly journals Covering Soybean Leaves With Cellulose Nanofiber Changes Leaf Surface Hydrophobicity and Confers Resistance Against Phakopsora pachyrhizi

2021 ◽  
Vol 12 ◽  
Author(s):  
Haruka Saito ◽  
Yuji Yamashita ◽  
Nanami Sakata ◽  
Takako Ishiga ◽  
Nanami Shiraishi ◽  
...  
Keyword(s):  
Leaf Surface ◽  
Surface Hydrophobicity ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Cellulose Nanofiber ◽  
Soybean Rust ◽  
Phakopsora Pachyrhizi ◽  
Chitin Synthases ◽  
Soybean Leaf ◽  
Soybean Leaves

Asian soybean rust (ASR) caused by Phakopsora pachyrhizi, an obligate biotrophic fungal pathogen, is the most devastating soybean production disease worldwide. Currently, timely fungicide application is the only means to control ASR in the field. We investigated cellulose nanofiber (CNF) application on ASR disease management. CNF-treated leaves showed reduced lesion number after P. pachyrhizi inoculation compared to control leaves, indicating that covering soybean leaves with CNF confers P. pachyrhizi resistance. We also demonstrated that formation of P. pachyrhizi appressoria, and also gene expression related to these formations, such as chitin synthases (CHSs), were significantly suppressed in CNF-treated soybean leaves compared to control leaves. Moreover, contact angle measurement revealed that CNF converts soybean leaf surface properties from hydrophobic to hydrophilic. These results suggest that CNF can change soybean leaf surface hydrophobicity, conferring resistance against P. pachyrhizi, based on the reduced expression of CHSs, as well as reduced formation of pre-infection structures. This is the first study to investigate CNF application to control field disease.

scholarly journals Covering soybean leaves with cellulose nanofiber changes leaf surface hydrophobicity and confers resistance against Phakopsora pachyrhizi

2020 ◽  
Author(s):  
Haruka Saito ◽  
Yuji Yamashita ◽  
Nanami Sakata ◽  
Takako Ishiga ◽  
Nanami Shiraishi ◽  
...  
Keyword(s):  
Leaf Surface ◽  
Surface Hydrophobicity ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Cellulose Nanofiber ◽  
Soybean Rust ◽  
Phakopsora Pachyrhizi ◽  
Infection Structures ◽  
Soybean Leaf ◽  
Soybean Leaves

AbstractAsian soybean rust (ASR) caused by Phakopsora pachyrhizi, an obligate biotrophic fungal pathogen, is the most devastating soybean production disease worldwide. Currently, timely fungicide application is the only means to control ASR in the field. We investigated cellulose nanofiber (CNF) application on ASR disease management. CNF-treated leaves showed reduced lesion number after P. pachyrhizi inoculation compared to control leaves, indicating that covering soybean leaves with CNF confers P. pachyrhizi resistance. We also demonstrated that formation of P. pachyrhizi pre-infection structures including germ-tubes and appressoria, and also gene expression related to these formations, such as chitin synthases (CHSs), were significantly suppressed in CNF-treated soybean leaves compared to control leaves. Moreover, contact angle measurement revealed that CNF converts soybean leaf surface properties from hydrophobic to hydrophilic. These results suggest that CNF can change soybean leaf surface hydrophobicity, conferring resistance against P. pachyrhizi, based on the reduced expression of CHSs, as well as reduced formation of pre-infection structures. This is the first study to investigate CNF application to control field disease.

scholarly journals Effects of Simplicillium lanosoniveum on Phakopsora pachyrhizi, the Soybean Rust Pathogen, and Its Use as a Biological Control Agent

2012 ◽  
Vol 102 (8) ◽  
pp. 749-760 ◽  
Author(s):  
N. A. Ward ◽  
C. L. Robertson ◽  
A. K. Chanda ◽  
R. W. Schneider
Keyword(s):  
Biological Control Agent ◽  
Signs And Symptoms ◽  
Control Agent ◽  
Soybean Rust ◽  
Phakopsora Pachyrhizi ◽  
Latent Stage ◽  
Leaf Surfaces ◽  
Rust Pathogen ◽  
Soybean Leaf ◽  
Soybean Leaves

The fungus Simplicillium lanosoniveum was isolated from soybean leaves infected with Phakopsora pachyrhizi, the soybean rust pathogen, in Louisiana and Florida. The fungus did not grow or become established on leaf surfaces until uredinia erupted, but when soybean rust signs and symptoms were evident, S. lanosoniveum colonized leaves within 3 days and sporulated within 4 days. Development of new uredinia was suppressed by about fourfold when S. lanosoniveum colonized uredinia. In the presence of S. lanosoniveum, uredinia became increasingly red-brown, and urediniospores turned brown and germinated at very low rates. Assays using quantitative real time polymerase chain reaction revealed that the fungus colonized leaf surfaces when plants were infected with P. pachyrhizi, either in a latent stage of infection or when symptoms were present. However, when plants were inoculated before infection, there was no increase of DNA of S. lanosoniveum, suggesting that the pathogen must be present in order for the antagonist to become established on soybean leaf surfaces. We documented significantly lower amounts of DNA of P. pachyrhizi and lower disease severity when soybean leaves were colonized with S. lanosoniveum. These studies documented the mycophilic and disease-suppressive nature of S. lanosoniveum.

scholarly journals Pathogenic Variation of Phakopsora pachyrhizi Isolates on Soybean in the United States from 2006 to 2009

Plant Disease ◽  
2012 ◽  
Vol 96 (1) ◽  
pp. 75-81 ◽  
Author(s):  
M. Twizeyimana ◽  
G. L. Hartman
Keyword(s):  
United States ◽  
Resistance Genes ◽  
The United States ◽  
Soybean Rust ◽  
Phakopsora Pachyrhizi ◽  
Soybean Genotype ◽  
Pathogenic Variation ◽  
Differential Set ◽  
Soybean Genotypes ◽  
Soybean Leaves

The introduction of Phakopsora pachyrhizi, the cause of soybean rust, into the United States is a classic case of a pathogen introduction that became established in a new geographical region overwintering on a perennial host (kudzu, Pueraria lobata). The objective of our study was to classify the pathogenic variation of P. pachyrhizi isolates collected in the United States, and to determine the spatial and temporal associations. In total, 72 isolates of P. pachyrhizi collected from infected kudzu and soybean leaves in the United States were purified, then established and increased on detached soybean leaves. These isolates were tested for virulence and aggressiveness on a differential set of soybean genotypes that included six genotypes with known resistance genes (Rpp), one resistant genotype without any known characterized resistance gene, and a susceptible genotype. Three pathotypes were identified among the 72 U.S. P. pachyrhizi isolates based on the virulence of these isolates on the genotypes in the differential set. Six aggressiveness groups were established based on sporulating-uredinia production recorded for each isolate on each soybean genotype. All three pathotypes and all six aggressiveness groups were found in isolates collected from the southern region and from both hosts (kudzu or soybean) in 2008. Shannon's index based on the number of pathotypes indicated that isolates from the South region were more diverse (H = 0.83) compared with the isolates collected in other regions. This study establishes a baseline of pathogenic variation of P. pachyrhizi in the United States that can be further compared with variation reported in other regions of the world and in future studies that monitor P. pachyrhizi virulence in association to deployment of rust resistance genes.

Influence of micro-nano surface texture on the hydrophobicity and corrosion resistance of a Ti6Al4V alloy surface

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Bochun Xu ◽  
Nan Zou ◽  
Yunhao Jia ◽  
Chao Feng ◽  
Jiajia Bu ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Titanium Alloy ◽  
Surface Texture ◽  
Surface Hydrophobicity ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Alloy Surface ◽  
Measurement Instruments ◽  
Content Type

Purpose The purpose of this paper is to study the effect of micro-nano surface texture on the corrosion resistance of a titanium alloy and investigate the correlation between corrosion resistance and hydrophobicity. Design/methodology/approach The surface of the Ti6Al4V alloy was modified by laser processing and anodizing to fabricate micro-pits, nanotubes and micro-nano surface textures. Afterward, the surface morphology, hydrophobicity and polarization curve of the samples were analyzed by cold field scanning electron microscopy, contact angle measurement instruments and a multi-channel electrochemical workstation. Findings The micro-nano surface texture can enhance the hydrophobicity of the Ti6Al4V surface, which may lead to better drag reduction to ease the friction of implants in vivo. Nevertheless, no correlation existed between surface hydrophobicity and corrosion resistance; the corrosion resistance of samples with nanotubes and high-density samples with micro-nano surface texture was extremely enhanced, indicating the similar corrosion resistance of the two. Research limitations/implications The mechanism of micro-dimples on the corrosion resistance of the micro-nano surface texture was not studied. Practical implications The density of micro-pits needs to be optimized to guarantee excellent corrosion resistance in the design of the micro-nano surface texture; otherwise, it will not fulfill the requirement of surface modification. Originality/value The influence of the micro-nano surface texture on the corrosion resistance, as well as the relationship between hydrophobicity and corrosion resistance of the titanium alloy surface, were systematically investigated for the first time. These conclusions offer new knowledge.

scholarly journals Proteomic Analysis of Soybean Leaves in a Compatible and an Incompatible Interaction with Phakopsora Pachyrhizi

2014 ◽  
Vol 1 (1) ◽  
Author(s):  
Mateus Rodrigues Pereira ◽  
Bianca Castro Gouvêa ◽  
Francismar Corrêa Marcelino-Guimarães ◽  
Humberto Josué de Oliveira Ramos ◽  
Maurilio Alves Moreira ◽  
...  
Keyword(s):  
Control Measure ◽  
Production Costs ◽  
Soybean Rust ◽  
Phakopsora Pachyrhizi ◽  
Fructose Bisphosphate ◽  
Soybean Genotypes ◽  
Fructose Bisphosphate Aldolase ◽  
Soybean Leaves ◽  
Dimensional Electrophoresis ◽  
Carbonic Anhydrase 1

AbstractAsian soybean rust (ASR), which is incited by the fungus Phakopsora pachyrhizi, is considered one of the most aggressive diseases to the soybean culture. There are no commercial cultivars immune to the pathogen and the control measure currently used is the application of fungicides that harms the environment and increases production costs. For a better understanding of the host’s response to the pathogen at the molecular level, two soybean genotypes were analyzed (PI561356, resistant to ASR and Embrapa 48, susceptible) at 72 hours and 192 hours after inoculation with spores of P. pachyrhizi. Leaf protein profiles of the plants were compared by two-dimensional electrophoresis associated with mass spectrometry (MS). Twenty-two protein spots presented different levels when the two treatments were compared (inoculated vs. non-inoculated). From those, twelve proteins were identified by MS analysis. Some of them are involved in metabolic pathways related to plant defense against pathogens, as in the case of carbonic anhydrase, 1-deoxy-D-xylulose- 5-phosphate reductoisomerase, fructose-bisphosphate aldolase and glutamine synthetase. The possible biochemical-physiological meanings of our findings are discussed.

scholarly journals Gene Expression in Leaves of Susceptible Glycine max during Infection with Phakopsora pachyrhizi Using Next Generation Sequencing

Sequencing ◽  
2011 ◽  
Vol 2011 ◽  
pp. 1-14 ◽  
Author(s):  
Arianne Tremblay ◽  
Parsa Hosseini ◽  
Nadim W. Alkharouf ◽  
Shuxian Li ◽  
Benjamin F. Matthews
Keyword(s):  
Soybean Rust ◽  
Cdna Libraries ◽  
Phakopsora Pachyrhizi ◽  
Rust Disease ◽  
Illumina Platform ◽  
Molecular Events ◽  
Genes Encoding ◽  
Exotic Pathogen ◽  
Soybean Leaves ◽  
Host Genes

Soybean rust is caused by the obligate biotrophic fungus Phakopsora pachyrhizi, an exotic pathogen causing important yield losses in soybean production. We used an mRNA-Seq strategy to analyze the expression pattern of soybean genes and better understand molecular events occurring in soybean following the infection. cDNA libraries were constructed from RNA isolated from whole infected soybean leaves 10 days after inoculation with P. pachyrhizi and sequenced using an Illumina platform to identify soybean genes that are affected by pathogen growth. We obtained 15 million sequences corresponding to soybean genes. Forty-two percent of the genes were downregulated including genes encoding proteins involved in amino acid metabolism, carbohydrate metabolism, and transport facilitation; 31% were upregulated including genes encoding proteins involved in lipid metabolism, glycan biosynthesis, and signal transduction. Candidate host genes identified in this study will be manipulated to assay their potential to control soybean rust disease.

scholarly journals The Importance of Phenolic Metabolism to Limit the Growth of Phakopsora pachyrhizi

2009 ◽  
Vol 99 (12) ◽  
pp. 1412-1420 ◽  
Author(s):  
Anatoliy V. Lygin ◽  
Shuxian Li ◽  
Ramya Vittal ◽  
Jack M. Widholm ◽  
Glen L. Hartman ◽  
...  
Keyword(s):  
Protective Role ◽  
Soybean Rust ◽  
Phakopsora Pachyrhizi ◽  
Phenolic Metabolism ◽  
Rust Infection ◽  
Resistant Lines ◽  
Significant Difference ◽  
Soybean Genotypes ◽  
Soybean Leaves

Understanding the metabolic responses of the plant to a devastating foliar disease, soybean rust, caused by Phakopsora pachyrhizi, will assist in development of cultivars resistant to soybean rust. In this study, differences in phenolic metabolism were analyzed between inoculated and noninoculated plants using two susceptible and three resistant soybean genotypes with known resistance genes. Rust infection resulted in increased accumulation of isoflavonoids and flavonoids in leaves of all soybean genotypes tested. Although the soybean phytoalexin glyceollin was not detected in leaves of uninfected plants, accumulation of this compound at marked levels occurred in rust-infected leaves, being substantially higher in genotypes with a red-brown resistant reaction. In addition, there was inhibition of P. pachyrhizi spore germination by glyceollin, formononetin, quercetin, and kaempferol. However, there was no correlation between concentrations of flavonoids quercetin and kaempferol and rust-induced isoflavonoid formononetin in soybean leaves and rust resistance. Lignin synthesis also increased in all inoculated soybean genotypes whereas there was no significant difference in all noninoculated soybean genotypes. Cell wall lignification was markedly higher in inoculated resistant lines compared with inoculated susceptible lines, indicating a possible protective role of lignin in rust infection development.

Hemocompatibility of TiO2 Nanoparticles Composite PTFE Coating for Medical Devices

2011 ◽  
Vol 299-300 ◽  
pp. 600-603 ◽  
Author(s):  
Li Li Xue ◽  
Ping Long ◽  
Huan Wei ◽  
Ying Liang
Keyword(s):  
Contact Angle ◽  
Medical Devices ◽  
Blood Clotting ◽  
Platelet Adhesion ◽  
Surface Hydrophobicity ◽  
Contact Angle Measurement ◽  
Organic Coating ◽  
Angle Measurement ◽  
Nano Particles ◽  
Systematic Evaluation

Hemocompatibility is a key property of biomaterials that come in contact with blood. Surface modification has shown great potential for improving the hemocompatibility of biomedical materials and devices. It has been improved that TiO2has excellent hemocompatibility. In this study, TiO2nanoparticles was added into polytetrafluorethylen (PTFE) resin in order to enhance hemocompatibility of the organic coating. The surface hydrophobicity of the coatings was characterized by contact angle measurement. Systematic evaluation of hemocompatibility, including platelet adhesion and blood clotting, proved that TiO2nanoparticles composite PTFE coating have better hemocompatibility. It is suggested that TiO2nano particles can improve hemocompatibility of organic coating due to its passive surface and chemical stability.

scholarly journals First Report of Phakopsora pachyrhizi Telia on Kudzu in the United States

Plant Disease ◽  
2006 ◽  
Vol 90 (3) ◽  
pp. 380-380 ◽  
Author(s):  
C. L. Harmon ◽  
P. F. Harmon ◽  
T. A. Mueller ◽  
J. J. Marois ◽  
G. L. Hartman
Keyword(s):  
United States ◽  
South Carolina ◽  
Leaf Surface ◽  
The United States ◽  
Visual Observation ◽  
Soybean Rust ◽  
Hypodermic Needle ◽  
Phakopsora Pachyrhizi ◽  
First Report ◽  
Telial Stage

Soybean rust caused by Phakopsora pachyrhizi H. Sydow & Sydow was first reported in the continental United States during 2004 (2). By 10 November 2005, the disease was confirmed in eight southern states (Florida, Georgia, Alabama, Mississippi, South Carolina, North Carolina, Louisiana, and Texas). Diagnoses have been based on visual observation of uredinia and urediniospores of the pathogen followed by polymerase chain reaction confirmation. On 10 November 2005, uredinia and telia were identified on leaves of kudzu (Pueraria lobata) in central Florida. Telia first were noted as dark brown-to-black flecks on the abaxial leaf surface intermingled with abundant tan-to-light brown uredinia. Of 200 leaves examined, 143 (72%) had telia. The number of telia ranged from a few (1/cm2) that were scattered to many (73/cm2). Telia were approximately the same diameter as uredinia, but were appressed to the leaf surface and pigmented. Twenty telia were excised from host tissue with the aid of a dissecting microscope and a 20 gauge hypodermic needle. Telia averaged 89 × 100 μm (n = 20, σ = 17 and 16 μm, respectively). Four telia were crushed and five teliospores from each averaged 4.3 × 8.3 μm (n = 20, σ = 0.5 and 0.9 μm, respectively). Pale yellowish brown-to-hyaline teliospores were similar in color to urediniospores. Observations matched descriptions by Ono et al. (1). To our knowledge, this is the first report of the telial stage of P. pachyrhizi in the United States. References: (1) Y. Ono et al. Mycol. Res. 96:825, 1992. (2) R. W. Schneider et al. Plant Dis. 89:774, 2005.

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