scholarly journals Characterization of Oryza rufipogon–Derived Resistance to Tungro Disease in Rice

Plant Disease ◽  
2007 ◽  
Vol 91 (11) ◽  
pp. 1386-1391 ◽  
Author(s):  
Yuji Shibata ◽  
Rogelio C. Cabunagan ◽  
Pepito Q. Cabauatan ◽  
Il-Ryong Choi
Keyword(s):  
Interspecific Hybridization ◽  
Resistance Mechanisms ◽  
Oryza Rufipogon ◽  
Rice Tungro Bacilliform Virus ◽  
Rice Cultivars ◽  
Susceptible Parent ◽  
Rice Tungro Spherical Virus ◽  
Rice Tungro Disease ◽  
Apparent Resistance

Rice tungro disease (RTD) is caused by the interaction between Rice tungro spherical virus (RTSV) and Rice tungro bacilliform virus (RTBV), both of which are transmitted by green leafhoppers (GLH). In order to define the resistance against RTD in rice cv. Matatag 9 which was developed by interspecific hybridization between RTD-susceptible cv. IR64 and Oryza rufipogon, the reactions of Matatag 9 to the viruses and GLH were evaluated in comparison with RTD-susceptible and -resistant rice cultivars. The incidences of infection with RTSV and RTBV in Matatag 9 were significantly lower than those in the susceptible parent cv. IR64; however, no substantial differences in virus accumulation were observed between IR64 and Matatag 9 once infected with the viruses. Symptoms in Matatag 9 infected with RTBV and RTSV were milder than those observed in IR64. A higher level of antixenosis to GLH was observed in Matatag 9 compared with IR64. The levels of antibiosis against GLH in Matatag 9 were comparable with those in another GLH-resistant cultivar, and significantly higher than those in RTD-susceptible cultivars. Collectively, these results suggest that tolerance to tungro viruses and resistance to GLH both contribute to the apparent resistance to RTD in Matatag 9, although possible involvement of other resistance mechanisms cannot be excluded.

Transfer of transgenes for resistance to rice tungro disease into high-yielding rice cultivars through gene-based marker-assisted selection

2012 ◽  
Vol 150 (5) ◽  
pp. 610-618 ◽  
Author(s):  
S. ROY ◽  
A. BANERJEE ◽  
J. TARAFDAR ◽  
B. K. SENAPATI ◽  
I. DASGUPTA
Keyword(s):  
Marker Assisted Selection ◽  
Rice Tungro Bacilliform Virus ◽  
35S Promoter ◽  
Rice Cultivars ◽  
Rice Tungro Spherical Virus ◽  
Challenge Inoculation ◽  
Rice Line ◽  
Rice Tungro Disease ◽  
Sense Orientation ◽  
Simultaneous Infection

SUMMARYRice tungro disease (RTD), caused by the simultaneous infection of rice tungro bacilliform virus (RTBV) and rice tungro spherical virus (RTSV), is one of the major threats to sustainable rice production in South and Southeast Asia. Transgenic resistance against RTBV has been reported previously using an RNA interference (RNAi) construct (ORF IV of RTBV, placed both in sense and anti-sense orientation under CaMV 35S promoter), in the scented rice line Pusa Basmati-1 (PB-1). This construct was transferred to two high-yielding tungro-susceptible indica rice cultivars (IET4094 and IET4786) from the transgenic PB-1 rice line using back cross breeding till the BC2F3 stage. On challenge inoculation, the progenies (BC2F1) showed mild symptoms of tungro, in contrast to severe symptoms displayed by the recurrent parents. Segregation of the transgene indicated near homozygosity of the plants at the BC2F3 stage, implying that the lines can be used as a valuable resistance source for further breeding against RTD.

scholarly journals Near Immunity to Rice Tungro Spherical Virus Achieved in Rice by a Replicase-Mediated Resistance Strategy

1999 ◽  
Vol 89 (11) ◽  
pp. 1022-1027 ◽  
Author(s):  
H. Huet ◽  
S. Mahendra ◽  
J. Wang ◽  
E. Sivamani ◽  
C. A. Ong ◽  
...  
Keyword(s):  
Antisense Rna ◽  
Rice Tungro Bacilliform Virus ◽  
Japonica Rice ◽  
Rice Tungro Spherical Virus ◽  
Rice Plants ◽  
Antisense Orientation ◽  
Rice Tungro Disease ◽  
Sense Orientation ◽  
Moderate Resistance ◽  
High Level

Rice tungro disease is caused by rice tungro bacilliform virus (RTBV), which is responsible for the symptoms, and rice tungro spherical virus (RTSV), which assists transmission of both viruses by leafhoppers. Transgenic japonica rice plants (Oryza sativa) were produced containing the RTSV replicase (Rep) gene in the sense or antisense orientation. Over 70% of the plants contained one to five copies of the Rep gene, with integration occurring at a single locus in most cases. Plants producing antisense sequences exhibited significant but moderate resistance to RTSV (60%); accumulation of antisense RNA was substantial, indicating that the protection was not of the homology-dependent type. Plants expressing the full-length Rep gene, as well as a truncated Rep gene, in the (+)-sense orientation were 100% resistant to RTSV even when challenged with a high level of inoculum. Accumulation of viral RNA was low, leading us to conclude that RTSV Rep-mediated resistance is not protein-mediated but is of the cosuppression type. Resistance was effective against geographically distinct RTSV isolates. In addition, RTSV-resistant transgenic rice plants were unable to assist transmission of RTBV. Such transgenic plants could be used in an epidemiological approach to combat the spread of the tungro disease.

scholarly journals Single Nucleotide Polymorphisms in a Gene for Translation Initiation Factor (eIF4G) of Rice (Oryza sativa) Associated with Resistance to Rice tungro spherical virus

2010 ◽  
Vol 23 (1) ◽  
pp. 29-38 ◽  
Author(s):  
Jong-Hee Lee ◽  
Muhammad Muhsin ◽  
Genelou A. Atienza ◽  
Do-Yeon Kwak ◽  
Suk-Man Kim ◽  
...  
Keyword(s):  
Translation Initiation ◽  
Recessive Gene ◽  
Translation Initiation Factor ◽  
Initiation Factor ◽  
Rice Tungro Bacilliform Virus ◽  
Nucleotide Polymorphisms ◽  
Rice Tungro Spherical Virus ◽  
Single Nucleotide ◽  
Rice Tungro Disease ◽  
Backcross Populations

Rice tungro disease (RTD) is a serious constraint to rice production in South and Southeast Asia. RTD is caused by Rice tungro spherical virus (RTSV) and Rice tungro bacilliform virus. Rice cv. Utri Merah is resistant to RTSV. To identify the gene or genes involved in RTSV resistance, the association of genotypic and phenotypic variations for RTSV resistance was examined in backcross populations derived from Utri Merah and rice germplasm with known RTSV resistance. Genetic analysis revealed that resistance to RTSV in Utri Merah was controlled by a single recessive gene (tsv1) mapped within an approximately 200-kb region between 22.05 and 22.25 Mb of chromosome 7. A gene for putative translation initiation factor 4G (eIF4Gtsv1) was found in the tsv1 region. Comparison of eIF4Gtsv1 gene sequences among susceptible and resistant plants suggested the association of RTSV resistance with one of the single nucleotide polymorphism (SNP) sites found in exon 9 of the gene. Examination of the SNP site in the eIF4Gtsv1 gene among various rice plants resistant and susceptible to RTSV corroborated the association of SNP or deletions in codons for Val1060-1061 of the predicted eIF4Gtsv1 with RTSV resistance in rice.

scholarly journals Suppression of Two Tungro Viruses in Rice by Separable Traits Originating from Cultivar Utri Merah

2009 ◽  
Vol 22 (10) ◽  
pp. 1268-1281 ◽  
Author(s):  
Jaymee R. Encabo ◽  
Pepito Q. Cabauatan ◽  
Rogelio C. Cabunagan ◽  
Kouji Satoh ◽  
Jong-Hee Lee ◽  
...  
Keyword(s):  
Serological Test ◽  
Gene Expression Pattern ◽  
Global Gene Expression ◽  
Rice Tungro Bacilliform Virus ◽  
Near Isogenic Lines ◽  
Rice Tungro Spherical Virus ◽  
Chain Reaction ◽  
Rice Tungro Disease ◽  
Polymerase Chain ◽  
The Individual

Rice tungro disease (RTD) is caused by Rice tungro spherical virus (RTSV) and Rice tungro bacilliform virus (RTBV) transmitted by green leafhoppers. Rice cv. Utri Merah is highly resistant to RTD. To define the RTD resistance of Utri Merah, near-isogenic lines (NIL, BC5 or BC6) developed from Utri Merah and susceptible cv. Taichung Native 1 (TN1) were evaluated for reactions to RTSV and RTBV. TW16 is an NIL (BC5) resistant to RTD. RTBV was able to infect both TN1 and TW16 but the levels of RTBV were usually significantly lower in TW16 than in TN1. Infection of RTSV was confirmed in TN1 by a serological test but not in TW16. However, the global gene-expression pattern in an RTSV-resistant NIL (BC6), TW16-69, inoculated with RTSV indicated that RTSV can also infect the resistant NIL. Infection of RTSV in TW16 was later confirmed by reverse-transcription polymerase chain reaction but the level of RTSV was considerably lower in TW16 than in TN1. Examination for virus accumulation in another NIL (BC6), TW16-1029, indicated that all plants of TW16-1029 were resistant to RTSV, whereas the resistance to RTBV and symptom severity were segregating among the individual plants of TW16-1029. Collectively, these results suggest that RTD resistance of Utri Merah involves suppression of interacting RTSV and RTBV but the suppression trait for RTSV and for RTBV is inherited separately.

scholarly journals Current Trends in Non-Invasive Imaging of Interactions in the Liver Tumor Microenvironment Mediated by Tumor Metabolism

Cancers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 3645
Author(s):  
Isabel Theresa Schobert ◽  
Lynn Jeanette Savic
Keyword(s):  
Tumor Microenvironment ◽  
Liver Cancer ◽  
Cancer Cells ◽  
Imaging Techniques ◽  
Treatment Strategies ◽  
Tumor Metabolism ◽  
Resistance Mechanisms ◽  
Metabolic Reprogramming ◽  
Non Invasive

With the increasing understanding of resistance mechanisms mediated by the metabolic reprogramming in cancer cells, there is a growing clinical interest in imaging technologies that allow for the non-invasive characterization of tumor metabolism and the interactions of cancer cells with the tumor microenvironment (TME) mediated through tumor metabolism. Specifically, tumor glycolysis and subsequent tissue acidosis in the realms of the Warburg effect may promote an immunosuppressive TME, causing a substantial barrier to the clinical efficacy of numerous immuno-oncologic treatments. Thus, imaging the varying individual compositions of the TME may provide a more accurate characterization of the individual tumor. This approach can help to identify the most suitable therapy for each individual patient and design new targeted treatment strategies that disable resistance mechanisms in liver cancer. This review article focuses on non-invasive positron-emission tomography (PET)- and MR-based imaging techniques that aim to visualize the crosstalk between tumor cells and their microenvironment in liver cancer mediated by tumor metabolism.

Characterization of carbapenem resistance mechanisms inKlebsiella pneumoniaeandin vitrosynergy of the colistin–meropenem combination

2014 ◽  
Vol 27 (5) ◽  
pp. 277-282 ◽  
Author(s):  
Lakshmana Gowda Krishnappa ◽  
Mohammed Ali M. Marie ◽  
Yazeed A. Al Sheikh
Keyword(s):  
Carbapenem Resistance ◽  
Resistance Mechanisms

scholarly journals Development of cytoplasmic male sterile lines and restorer lines of various elite Indica Group rice cultivars using CW-CMS/Rf17 system

Rice ◽  
2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Kinya Toriyama ◽  
Tomohiko Kazama ◽  
Tadashi Sato ◽  
Yoshimichi Fukuta ◽  
Masaaki Oka
Keyword(s):  
Nuclear Gene ◽  
Oryza Rufipogon ◽  
Rice Cultivars ◽  
Male Sterile ◽  
Cytoplasmic Male Sterile ◽  
Cms Line

Abstract Background A cytoplasm of CW-type cytoplasmic male sterile (CMS) line is derived from Oryza rufipogon strain W1 and fertility is restored by a single nuclear gene, Rf17. We have previously reported that CW-CMS were effective for breeding CMS lines of Indica Group rice cultivars, IR 24 and IR 64. The applicability of this CW-CMS/Rf17 system to produce other elite Indica Group rice cultivars with CMS was explored. Findings Out of seven elite Indica Group rice cultivars, complete CMS lines were obtained for six cultivars: NSIC Rc 160, NSIC Rc 240, Ciherang, BRRI dhan 29, NERICA-L-19, and Pusa Basmati. The fertility of these six lines was restored when Rf17 was present. A CMS line was not obtained for the cultivar Samba Mahsuri. Conclusions The CW-CMS/Rf17 system will be useful to produce CMS lines and restorer lines of various elite Indica Group rice cultivars.

scholarly journals Characterization of resistance mechanisms of Enterobacter cloacae Complex co-resistant to carbapenem and colistin

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Shixing Liu ◽  
Renchi Fang ◽  
Ying Zhang ◽  
Lijiang Chen ◽  
Na Huang ◽  
...  
Keyword(s):  
Lipid A ◽  
Efflux Pump ◽  
Resistance Mechanism ◽  
Carbapenem Resistance ◽  
Enterobacter Cloacae ◽  
Resistance Mechanisms ◽  
Colistin Resistance ◽  
Carbapenem Resistant ◽  
Horizontal Spread

Abstract Background The emergence of carbapenem-resistant and colistin-resistant ECC pose a huge challenge to infection control. The purpose of this study was to clarify the mechanism of the carbapenems and colistin co-resistance in Enterobacter cloacae Complex (ECC) strains. Results This study showed that the mechanisms of carbapenem resistance in this study are: 1. Generating carbapenemase (7 of 19); 2. The production of AmpC or ESBLs combined with decreased expression of out membrane protein (12 of 19). hsp60 sequence analysis suggested 10 of 19 the strains belong to colistin hetero-resistant clusters and the mechanism of colistin resistance is increasing expression of acrA in the efflux pump AcrAB-TolC alone (18 of 19) or accompanied by a decrease of affinity between colistin and outer membrane caused by the modification of lipid A (14 of 19). Moreover, an ECC strain co-harboring plasmid-mediated mcr-4.3 and blaNDM-1 has been found. Conclusions This study suggested that there is no overlap between the resistance mechanism of co-resistant ECC strains to carbapenem and colistin. However, the emergence of strain co-harboring plasmid-mediated resistance genes indicated that ECC is a potential carrier for the horizontal spread of carbapenems and colistin resistance.

Characterization of Hungarian rice cultivars in nitrogen fixing associations with bacteria

2000 ◽  
Vol 28 (1-2) ◽  
pp. 9-16 ◽  
Author(s):  
Beatrix Rethati ◽  
Klara Dallmann ◽  
Ibolya K. Simon ◽  
Andor Balint ◽  
Bela Szajani ◽  
...  
Keyword(s):  
Rice Cultivars ◽  
Nitrogen Fixing

Red Rice (Oryza sativa) Biology. I. Characterization of Red Rice Ecotypes

1999 ◽  
Vol 13 (1) ◽  
pp. 12-18 ◽  
Author(s):  
José A. Noldin ◽  
James M. Chandler ◽  
Garry N. McCauley
Keyword(s):  
Flag Leaf ◽  
Natural Hybridization ◽  
Rice Cultivars ◽  
Red Rice ◽  
Cultivated Rice ◽  
Seed Shattering ◽  
Seed Moisture ◽  
Biology I ◽  
Plant Characteristics

Plant characteristics of red rice ecotypes obtained from Arkansas, Louisiana, Mississippi, and Texas, including 11 strawhulled, five blackhulled, two goldhulled, and one brownhulled type, were evaluated under field conditions. Most ecotypes were uniform and stable but manifested considerable genetic variability. Red rice plants had pubescent leaves, were taller with lighter green color, and produced more tillers and panicles per plant than rice cultivars ‘Lemont,’ ‘Mars,’ and ‘Maybelle.’ Most ecotypes were highly susceptible to seed shattering starting about 14 d after anthesis when seed moisture was more than 25%. Seeds of most ecotypes were highly dormant at harvest. Rice cultivars had a larger flag leaf and more total leaf area per plant at anthesis and produced more seeds per panicle than red rice. Some red rice ecotypes had plant characteristics closely related to cultivated rice suggesting natural hybridization with rice.

Sign in / Sign up

Export Citation Format

Share Document