• Plant Biotechnology Reports
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• v.2 no.1
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• pp.75-85
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• 2008

Prune dwarf virus (PDV) is an Ilarvirus systemically infecting almond trees and other Prunus species and spreading through pollen, among other means. We have studied strategies based on coat protein (cp) gene to block PDV replication in host plant cells. A Portuguese isolate of PDV was obtained from infected almond leaves and used to produce the cDNA of the cp gene. Various constructs were prepared based on this sequence, aiming for the transgenic expression of the original or modified PDV coat protein (cpPDVSense and cpPDVMutated) or for the expression of cpPDV RNA (cpPDVAntisense and cpPDVwithout start codon). All constructs were tested in a PDV host model, Nicotiana benthamiana, and extensive molecular characterization and controlled infections were performed on transformants and their progenies. Transgenic plants expressing the coat protein RNA were able to block the proliferation of a PDV isolate sharing only 91% homology with the isolate used for cpPDV cloning, as evaluated by DAS-ELISA on newly developed leaves. With cp expression, the blockage of PDV proliferation in newly developed leaves was only achieved with the construct cpPDV Mutated, where the coat protein has a substitution in the 14th aa residue, with arginine replaced by alanine. This result points to a possible role of the mutated amino acid in the virus ability to replicate and proliferate. This work reveals the possibility of achieving protection against PDV through either coat protein RNA or mutated cp sequence.

• The Plant Pathology Journal
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• v.37 no.6
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• pp.632-640
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• 2021

Cucumber mosaic virus (CMV) and Pepper mild mottle virus (PMMoV) causes severe economic loss in crop productivity of both agriculture and horticulture crops in Korea. The previous surveys showed that naturally available biopolymer material - chitosan (CS), which is from shrimp cells, reduced CMV accumulation on pepper. To improve the antiviral activity of CS, it was synthesized to form phosphate cross-linked chitosan (PCS) and compared with the original CS. Initially, the activity of CS and PCS (0.01%, 0.05%, and 0.1% concentration) compound against PMMoV infection and replication was tested using a half-leaf assay on Nicotiana glutinosa leaves. The total number of local lesions represented on a leaf of N. glutinosa were counted and analyzed with phosphate buffer treated leaves as a negative control. The leaves treated with a 0.1% concentration of CS or PCS compounds exhibited an inhibition effect by 40-75% compared with the control leaves. The same treatment significantly reduced about 40% CMV accumulation measured by double antibody sandwich enzyme-linked immunosorbent assay and increased the relative expression levels of the NPR1, PR-1, cysteine protease inhibitor gene, LOX, PAL, SRC2, CRF3 and ERF4 genes analyzed by quantitative reverse transcriptase-polymerase chain reaction, in chili pepper plants.

• The Plant Pathology Journal
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• v.38 no.6
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• pp.646-655
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• 2022

Pepper mild mottle virus (PMMoV), one of the most prevalent viruses in chili pepper (Capsicum annuum L.) is a non-enveloped, rod-shaped, single-stranded positive-sense RNA virus classified in the genus Tobamovirus. The supernatants of five bacterial cultures (Pseudomonas putida [PP], Bacillus licheniformis [BLI], P. fluorescens [PF], Serratia marcescens [SER], and B. amyloliquifaciens [BA]) were analyzed to find novel antiviral agents to PMMoV in chili pepper. Foliar spraying with supernatants (1:1, v/v) obtained from Luria-Bertani broth cultures of PP, BLI, PF, SER, and BA inhibited PMMoV infection of chili pepper if applied before the PMMoV inoculation. Double-antibody sandwich enzyme-linked immunosorbent assay showed that treatments of five supernatants resulted in 51-66% reductions in PMMoV accumulation in the treated chili pepper. To identify key compounds in supernatants of PP, BLI, PF, SER, and BA, the supernatants were subjected to gas chromatography-mass spectrometry. The 24 different types of compounds were identified from the supernatants of PP, BLI, PF, SER, and BA. The compounds vary from supernatants of one bacterial culture to another which includes simple compounds-alkanes, ketones, alcohols, and an aromatic ring containing compounds. The compounds triggered the inhibitory effect on PMMoV propagation in chili pepper plants. In conclusion, the cultures could be used to further conduct tissue culture and field trial experiments as potential bio-control agents.

• Research in Plant Disease
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• v.8 no.2
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• pp.101-106
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• 2002

For the detection of Tobacco masaic virus (TMV), Tomato mosaic virus (ToMV), and Cucumber mosaic virus (CMV), tomato seeds of 11 table tomato and 7 cherry tomato cultivars were assayed by DAS-ELISA. Among the cultivars, TMV and ToMV were detected from 9 cultivars at the rates lower than 20% and 16%, respectively. In the assay on seed transmission rates, ToMV and CMV were detected as high as 24% and 8% , respectively, but TMV was not detected. In field survey on these viruses from tomato plants of 10 different places in Chungbuk province, ToMV and CMV were detected from most fields. TMV was detected from only 3 fields. The highest detection rates of these viruses were recorded in Cheongwon for TMV Chungju for ToMV, and the other locality of Chungju far CMV. It was difficult to find any relationship between the growth stage of tomato and infection rates. TMV usually caused mosaic on leaves while ToMV caused various symptoms including yellows, necrosis, and mottling. CMV-infected tomato plants showed symptoms of shoestring, fern leaf, and yellows.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.8
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• pp.1119-1126
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• 2018

Objective: Present investigation was aimed to study the Single Nucleotide Variants of the luteinizing hormone beta ($LH{\beta}$) gene and to analyze their association with the semen quality (fresh and post-thawed frozen semen) and luteinizing hormone (LH) concentrations in Murrah buffalo bulls. Methods: Polymerase chain reaction-single stranded conformational polymorphism (PCR-SSCP) and Sanger sequencing method is used to study genetic variability in $LH{\beta}$ gene. LH assay was carried out using enzyme-linked immunosorbent assay method. A fixed general linear model was used to analyze association of single nucleotide polymorphism (SNP) of $LH{\beta}$ gene with semen quality in 109 and LH concentrations in 80 Murrah bulls. Results: $LH{\beta}$ gene was found to be polymorphic. Total six SNPs were identified in $LH{\beta}$ gene g C356090A, g C356113T, g A356701G, g G355869A, g G356330C, and g G356606T. Single Stranded Conformational Polymorphism variants of pattern 2 of exon 1+pattern 2 of exon 2+pattern 1 of exon 3 had highly significant (p<0.01) effect on sperm concentration (million/mL), percent mass motility, acrosome integrity and membrane integrity in fresh and frozen semen whereas significant (p<0.05) effect was observed on percent live spermatozoa. SSCP variants of pattern 2 of exon 1+pattern 2 of exon 2+pattern 1 of exon 3 had highly significant (p<0.01) effect on luteinizing hormone concentrations too. Conclusion: The observed association between SSCP variants of $LH{\beta}$ gene with semen quality parameters and LH concentrations indicated the possibilities of using $LH{\beta}$ as a candidate gene for identification of markers for semen quality traits and LH concentrations in Murrah buffaloes.