The rice stripe virus

Rice stripe virus (RSV) is a member of the Tenuivirus genus. It causes chlorotic stripes, chlorosis, moderate stunting and loss of vigour.  Severe infections cause the leaves of the plant to develop brown to grey necrotic streaks. If infection is massive the plant dies. The virus occurs in rice, maize, wheat, oat, foxtail millet and wild grasses of the family Gramineae. It does not infect members of other families.

The virus is transmitted by Laodelphax striatellus and three other planthopper species. It occurs in rice-growing areas of Asia and Russia, and causes significant reduction in rice yield.

Kim et al 2012 identified 21 potential rice stripe virus resistance factors and explained their association with the host resistance factors within a network model. [1]

Gutiérrez et al 2010 studied the genetics of the African rice Oryza glaberrima MG12 (acc. IRGC103544), compared to Oryza sativa ssp. tropical japonica (cv. Caiapó). The authors found a strong segregation distortion on chromosomes 3 and 6, which suggests the presence of  interspecific sterility genes. This may help to overcome  hybrid sterility barriers between species of rice. Fourteen loci for plant height, tiller number per plant, panicle length, sterility percentage, 1000-grain weight and grain yield were located by the authors at chromosomes 1, 3, 4, 6 and 9. A locus controlling resistance to the Rice stripe necrosis virus was located between SSR markers RM202-RM26406 (44.5-44.8 cM) on chromosome 11. [2]

In a study of Li et al 2012, it was demonstrated that NS3 gene produce the highest expression in both, rice plants and the virus vector, the small brown planthopper, and disease-specific protein (SP) gene was the only gene with highest expression in rice, but was not present in planthopper.  [3]

Zhou et al 2012 introduced a RNAi construct containing coat protein gene (CP) and disease specific protein gene (SP) sequences from rice stripe virus into varieties of rice in varieties of rice. The transgenic plants were strongly resistant to viral infection, and viral replication of SP and CP was significantly inhibited. The authors suggest that the introduction of such a RNAi may reduce  the vulnerability of rice varieties to  the rice stripe virus. [4]

[1] Kim K, Choi D, Kim SM, Kwak DY, Choi J, Lee S, Lee BC, Hwang D, Hwang I: A Systems Approach for Identifying Resistance Factors to Rice stripe virus. Mol Plant Microbe Interact. 2012 Apr;25(4):534-45. doi.10.1094/MPMI-11-11-0282
http://www.ncbi.nlm.nih.gov/pubmed/22217248

[2] Gutiérrez AG, Carabalí SJ, Giraldo OX, Martínez CP, Correa F, Prado G, Tohme J, Lorieux M: Identification of a Rice stripe necrosis virus resistance locus and yield component QTLs using Oryza sativa x O. glaberrima introgression lines.BMC Plant Biol. 2010 Jan 8;10:6.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2824796/?tool=pubmed

[3].Li S, Li X, Sun L, Zhou Y: Analysis of rice stripe virus whole-gene expression in rice and in the small brown planthopper by real-time quantitative PCR.  Acta Virol. 2012;56(1):75-9
http://www.ncbi.nlm.nih.gov/pubmed/22404613

[4] Zhou Y, Yuan Y, Yuan F, Wang M, Zhong H, Gu M, Liang G: RNAi-directed down-regulation of RSV results in increased resistance in rice (Oryza sativa L.).Biotechnol Lett. 2012 Jan 20.
http://www.ncbi.nlm.nih.gov/pubmed/22261864