Bakanae disease (BD) has emerged as a serious threat in almost all rice cultivation regions worldwide. Nampyeong is a Korean japonica rice variety known to be resistant to BD. In this study, quantitative trait locus (QTL) mapping was performed with F2 and F3 plants derived from a cross between the Nampyeong variety and a susceptible Korean japonica line, DongjinAD.
View Article and Find Full Text PDFFlavonoids and carotenoids of pigmented rice ( Oryza sativa L.), including five black cultivars and two red cultivars, from Korea were characterized to determine the diversity among the phytochemicals and to analyze the relationships among their contents. Black cultivars were higher in flavonoids and carotenoids than the red and white cultivars.
View Article and Find Full Text PDFEstimation of the protein levels introduced in a biotechnology-derived product is conducted as part of an overall safety assessment. An enzyme-linked immunosorbent assay (ELISA) was used to analyze phosphinothricin acetyltransferase (PAT) and neomycin phosphotransferase II (NPT II) protein expression in a genetically modified (GM) pepper plant developed in Korea. PAT and NPT II expression levels, based on both dry weight and fresh weight, were variable among different plant generations and plant sections from isolated genetically modified organism (GMO) fields at four developmental stages.
View Article and Find Full Text PDFCoordination of multiple transgenes is essential for metabolic engineering of biosynthetic pathways. Here, we report the utilization of two bicistronic systems involving the 2A sequence from the foot-and-mouth disease virus and the internal ribosome entry site (IRES) sequence from the crucifer-infecting tobamovirus to the biosynthesis of carotenoids in rice endosperm. Two carotenoid biosynthetic genes, phytoene synthase (Psy) from Capsicum and carotene desaturase (CrtI) from Pantoea, were linked via either the synthetic 2A sequence that was optimized for rice codons or the IRES sequence under control of the rice globulin promoter, generating PAC (Psy-2A-CrtI) and PIC (Psy-IRES-CrtI) constructs, respectively.
View Article and Find Full Text PDFAlthough susceptibility to seed shattering causes severe yield loss during cereal crop harvest, it is an adaptive trait for seed dispersal in wild plants. We previously identified a recessive shattering locus, sh-h, from the rice shattering mutant line Hsh that carries an enhanced abscission layer. Here, we further mapped sh-h to a 34-kb region on chromosome 7 by analyzing 240 F(2) plants and five F(3) lines from the cross between Hsh and Blue&Gundil.
View Article and Find Full Text PDFTo increase insect resistance in transgenic rice plants, a synthetic truncated cry1Ac gene was linked to the rice rbcS promoter and its transit peptide sequence (tp) for chloroplast-targeted expression. Several transgenic lines were generated by the Agrobacterium-mediated transformation method and the expression levels of the transgene were compared with untargeted expression. Use of the rbcS-tp sequence increased the cry1Ac transcript and protein levels by 25- and 100-fold, respectively, with the accumulated protein in chloroplasts comprising up to 2% of the total soluble proteins.
View Article and Find Full Text PDFABSTRACT Cochliobolus miyabeanus forms a specialized infection structure, an appressorium, to infect its host rice plants. Curtailment of prepenetration development by spermidine and spermine was more evident in appressorium development and germination remained unaffected, whereas putrescine and methylglyoxal-bis-guanyl hydrazone (MGBG) impaired both morphogenetic events. Exogenous calcium nullified the inhibitory effect of MGBG on the prepenetration development in vitro and in vivo and the disease progression.
View Article and Find Full Text PDFABSTRACT Responses of rice to Magnaporthe grisea and Cochliobolus miyabeanus were compared. In Tetep, a rice cultivar resistant to both fungi, pathogen inoculation rapidly triggered the hypersensitive reaction (HR), resulting in microscopic cell death. In rice cv.
View Article and Find Full Text PDFThe brown planthopper (BPH) is a major insect pest in rice, and damages these plants by sucking phloem-sap and transmitting viral diseases. Many BPH resistance genes have been identified in indica varieties and wild rice accessions, but none has yet been cloned. In the present study we report fine mapping of the region containing the Bph1 locus, which enabled us to perform marker-aided selection (MAS).
View Article and Find Full Text PDFThe quantitative trait loci (QTLs) for the dead leaf rate (DLR) and the dead seedling rate (DSR) at the different rice growing periods after transplanting under alkaline stress were identified using an F(2:3) population, which included 200 individuals and lines derived from a cross between two japonica rice cultivars Gaochan 106 and Changbai 9 with microsatellite markers. The DLR detected at 20 days to 62 days after transplanting under alkaline stress showed continuous normal or near normal distributions in F(3) lines, which was the quantitative trait controlled by multiple genes. The DSR showed a continuous distribution with 3 or 4 peaks and was the quantitative trait controlled by main and multiple genes when rice was grown for 62 days after transplanting under alkaline stress.
View Article and Find Full Text PDFOSH6 (Oryza sativa Homeobox6) is an ortholog of lg3 (Liguleless3) in maize. We generated a novel allele, termed OSH6-Ds, by inserting a defective Ds element into the third exon of OSH6, which resulted in a truncated OSH6 mRNA. The truncated mRNA was expressed ectopically in leaf tissues and encoded the N-terminal region of OSH6, which includes the KNOX1 and partial KNOX2 subdomains.
View Article and Find Full Text PDFInsertional mutagen-mediated gene tagging populations have been essential resources for analyzing the function of plant genes. In rice, maize transposable elements have been successfully utilized to produce transposant populations. However, many generations and substantial field space are required to obtain a sufficiently sized transposant population.
View Article and Find Full Text PDFMol Plant Microbe Interact
July 2007
A nonpathogenic rhizobacterium, Pseudomonas putida LSW17S, elicited systemic protection against Fusarium wilt and pith necrosis caused by Fusarium oxysporum f. sp. lycopersici and P.
View Article and Find Full Text PDFThiamine confers systemic acquired resistance (SAR) on susceptible plants through priming, leading to rapid counterattack against pathogen invasion and perturbation of disease progress. Priming reduces the metabolic cost required for constitutive expression of acquired resistance. To investigate the effects of priming by thiamine on defense-related responses, Arabidopsis (Arabidopsis thaliana) was treated with thiamine and effects of pathogen challenge on the production of active oxygen species, callose deposition, hypersensitive cell death, and pathogenesis-related 1 (PR1)/Phe ammonia-lyase 1 (PAL1) gene expression was analyzed.
View Article and Find Full Text PDFBy a differential cDNA screening technique, we have isolated a dehydration-inducible gene (designated OSRK1) that encodes a 41.8 kD protein kinase of SnRK2 family from Oryza sativa. The OSRK1 transcript level was undetectable in vegetative tissues, but significantly increased by hyperosmotic stress and Abscisic acid (ABA).
View Article and Find Full Text PDFWe isolated HvRAF (Hordeum vulgare root abundant factor), a cDNA encoding a novel ethylene response factor (ERF)-type transcription factor, from young seedlings of barley. In addition to the most highly conserved APETALA2/ERF DNA-binding domain, the encoded protein contained an N-terminal MCGGAIL signature sequence, a putative nuclear localization sequence, and a C-terminal acidic transcription activation domain containing a novel mammalian hemopexin domain signature-like sequence. Their homologous sequences were found in AAK92635 from rice and RAP2.
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