Assessment of resistance to rice tungro disease in popular rice varieties in India by introgression of a transgene against Rice tungro bacilliform virus

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.

Download Full-text

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

Phytopathology ◽

10.1094/phyto.1999.89.11.1022 ◽

1999 ◽

Vol 89 (11) ◽

pp. 1022-1027 ◽

Cited By ~ 30

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.

Download Full-text

Complete Genome Sequence of Rice Tungro Bacilliform Virus Infecting Asian Rice (Oryza sativa) in Malaysia

Microbiology Resource Announcements ◽

10.1128/mra.00262-19 ◽

2019 ◽

Vol 8 (20) ◽

Author(s):

Maathavi Kannan ◽

Maisarah Mohamad Saad ◽

Noraini Talip ◽

Syarul Nataqain Baharum ◽

Hamidun Bunawan

Keyword(s):

Oryza Sativa ◽

Genome Sequence ◽

Complete Genome Sequence ◽

Complete Genome ◽

Rice Tungro Bacilliform Virus ◽

Asian Rice ◽

Rice Tungro Disease

Rice tungro disease was discovered in Malaysia in the 1930s. The first and only genome of Rice tungro bacilliform virus (RTBV) isolated from rice in Malaysia was sequenced in 1999.

Download Full-text

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

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-23-1-0029 ◽

2010 ◽

Vol 23 (1) ◽

pp. 29-38 ◽

Cited By ~ 52

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.

Download Full-text

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

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-22-10-1268 ◽

2009 ◽

Vol 22 (10) ◽

pp. 1268-1281 ◽

Cited By ~ 15

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.

Download Full-text

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

Plant Disease ◽

10.1094/pdis-91-11-1386 ◽

2007 ◽

Vol 91 (11) ◽

pp. 1386-1391 ◽

Cited By ~ 19

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.

Download Full-text

Recovering Ability of Upland and Rainfed Lowland Rice Varieties against Rice Tungro Disease

Bangladesh Rice Journal ◽

10.3329/brj.v21i1.37390 ◽

2018 ◽

Vol 21 (1) ◽

pp. 91-100 ◽

Cited By ~ 1

Author(s):

MT Khatun ◽

MA Latif ◽

MM Rahman ◽

M Hossain ◽

TH Ansari ◽

...

Keyword(s):

Upland Rice ◽

Lowland Rice ◽

Resistant Variety ◽

Yield Reduction ◽

Insect Vector ◽

Rice Varieties ◽

Rice Tungro Disease ◽

Rainfed Lowland ◽

Endemic Areas ◽

Almost All

Rice tungro is the most destructive and widespread among virus diseases found in almost all rice growing areas. In susceptible varieties, it causes 100% yield loss under favourable environmental conditions. Control of tungro disease by chemical applications is not effective and eco-friendly. Development of resistant variety against tungro is also difficult, because it is necessary to develop resistance either to the insect vector or to the virus or to the both. Identification of varieties with recovering ability will facilitate farmers to cultivate rice in tungro endemic areas. Bangladesh Rice Research Institute released six upland and eight rainfed lowland rice varieties, which were tested to evaluate their recovering ability against tungro disease. The test varieties including susceptible and resistant checks were artificially inoculated by viruliferous vector (Green leafhopper, Nephotettix virescens) of ten days after seeding in net house condition. Among the tested varieties BR26, BRRI dhan33 and BRRI dhan40 were the most susceptible and showed high infection rate against tungro disease. BRRI dhan37 and BR8 showed the highest recovering ability in rainfed lowland and upland rice, respectively, with the lowest yield reduction compared to the resistant check Kumragoir, which could be used in tungro endemic areas. From these investigations, all the tested varieties expressed distinct tungro disease symptoms after three weeks of inoculation. With the advancement of plant growth, varieties BR8 and BRRI dhan37 recovered from tungro syndrome due to their genetic makeup consisting tolerance potentiality showed better yield, while other varieties like BRRI dhan33 and BRRI dhan40 did not produce any grain yieldBangladesh Rice j. 2017, 21(1): 91-100

Download Full-text

On the Germination of Seeds of Rice Varieties at Low Temperatures : Preliminary

Japanese Journal of Crop Science ◽

10.1626/jcs.2.263 ◽

1930 ◽

Vol 2 (4) ◽

pp. 263-268 ◽

Cited By ~ 1

Author(s):

KIYOKATSU MATSUDA

Keyword(s):

Low Temperatures ◽

Rice Varieties

Download Full-text

Studies on the yield abilities of the rice varieties in Japan : Continued

Japanese Journal of Crop Science ◽

10.1626/jcs.17.17 ◽

1948 ◽

Vol 17 (1) ◽

pp. 17-20 ◽

Cited By ~ 1

Author(s):

Isamu Morimoto

Keyword(s):

Rice Varieties

Download Full-text

Glycaemic responses to glucose and rice in people of Chinese and European ethnicity

10.26686/wgtn.12831854 ◽

2020 ◽

Author(s):

M Kataoka ◽

BJ Venn ◽

SM Williams ◽

Lisa Te Morenga ◽

IM Heemels ◽

...

Keyword(s):

Ethnic Differences ◽

Rice Variety ◽

Glycaemic Index ◽

Activity Levels ◽

Glycaemic Response ◽

Rice Varieties ◽

Adjusted Risk ◽

Postprandial Glycaemia ◽

Adjusted Risk Ratio ◽

Glucose Curve

Aims: Diabetes rates are especially high in China. Risk of Type 2 diabetes increases with high intakes of white rice, a staple food of Chinese people. Ethnic differences in postprandial glycaemia have been reported. We compared glycaemic responses to glucose and five rice varieties in people of European and Chinese ethnicity and examined possible determinants of ethnic differences in postprandial glycaemia. Methods: Self-identified Chinese (n = 32) and European (n = 31) healthy volunteers attended on eight occasions for studies following ingestion of glucose and jasmine, basmati, brown, Doongara® and parboiled rice. In addition to measuring glycaemic response, we investigated physical activity levels, extent of chewing of rice and salivary α-amylase activity to determine whether these measures explained any differences in postprandial glycaemia. Results: Glycaemic response, measured by incremental area under the glucose curve, was over 60% greater for the five rice varieties (P < 0.001) and 39% greater for glucose (P < 0.004) amongst Chinese compared with Europeans. The calculated glycaemic index was approximately 20% greater for rice varieties other than basmati (P = 0.01 to 0.05). Ethnicity [adjusted risk ratio 1.4 (1.2-1.8) P < 0.001] and rice variety were the only important determinants of incremental area under the glucose curve. Conclusions: Glycaemic responses following ingestion of glucose and several rice varieties are appreciably greater in Chinese compared with Europeans, suggesting the need to review recommendations regarding dietary carbohydrate amongst rice-eating populations at high risk of diabetes. © 2012 Diabetes UK.

Download Full-text