|
Rice ragged stunt virus (RRSV) is a plant pathogenic virus of the family Reoviridae. Family: Reoviridae Genus: Oryzavirus Species: Rice ragged stunt virus Acronym: RRSV Rice ragged stunt virus (RRSV), vectored by the brown planthopper (BPH) (Delphacidae: ''Nilaparvata lugens''), causes ragged stunt disease of rice (Oryza spp., especially ''Oryza sativa'').〔(AAB (Descriptions of Plant Viruses ))〕 The virus, first described by Hibino, Ling and Shikata,〔Hibino, Roechan, Sudarisman & Tantera, Contr. cent. Res. Inst. Agric., Bogor, Indonesia No. 35, 15 pp., 1977〕〔Ling, Int. Rice Res. Newsl. 2(5): 6, 1977.〕〔Shikata, Leelapanang, Tiongco & Ling, Int. Rice Res. Newsl. 2(5): 7, 1977.〕 is also less commonly known as rice infectious gall virus.〔Bergonia, Philipp. Phytopath. 13: 2, 1977.〕 RRSV has polyhedral particles c. 50 nm in diameter possessing spikes (and perhaps a complete outer shell) to a diameter of 65 nm. The particles contain double-stranded RNA in 8 segments. RRSV can only infect plants in the family Gramineae, i.e. grasses including rice. The virus can only be transmitted by BPH and is not mechanically transmitted to plants. Rice plants infected with RRSV are stunted with whitish spindle-shaped outgrowths. Later the infected leaves become twisted with ragged edges, and may eventually turn brown. Rice plants may survive the infection, but yields are greatly reduced due to delayed flowering, incomplete panicle emergence, and unfilled grains.〔Shikata, Senboku, Kamjaipai, Chou, Tiongco & Ling, Ann. phytopath. Soc. Japan 45: 436, 1979.〕 Symptoms of RRSV infection vary with the variety of rice and stage of growth. Most rice varieties of ''Oryza sativa japonica'' and ''Oryza sativa indica'', are susceptible to RRSV though several resistant varieties are available.〔Ghosh & John, Pl. Dis. 64: 1032, 1980.〕 Attempts to prevent RRSV infections by controlling BPH with insecticides, often have the opposite effect of facilitating RRSV outbreaks. This can due to a disproportionate effect of insecticides on the natural enemies of BPH. Certain types of insecticides (e.g. triazophos), actually increase the birthrates of BPH through their effects on the reproductive systems of male and female planthoppers.〔Ge, Lin-Quan; Yao Chen , Jin-Cai Wu , and Gary C Jahn. 2011. (Proteomic analysis of insecticide triazophos-induced mating–responsive proteins of Nilaparvata lugens Stål (Hemiptera:Delphacidae). ) J. Proteome Res.. .〕〔Wang, LP, Jun Shen, Lin-Quan Ge, Jin-Cai Wu, Guo-Qin Yang, Gary C. Jahn. 2010. (Insecticide-induced increase in the protein content of male accessory glands and its effect on the fecundity of females in the brown planthopper, ''Nilaparvata lugens'' Stål (Hemiptera: Delphacidae ). Crop Protection 29:1280–1285.〕 The increase in BPH populations not only increases the incidence of RRSV within a field, but as the BPH become crowded they transform into long-winged migratory forms (known as macropterous forms) and spread RRSV to fields up to hundreds of kilometers away.〔Denno RF, Roderick GK, Olmstead KL, Dobel HG. 1991. (Density-related migration in planthoppers (Homoptera: Delphacidae): the role of habitat persistence ). Am. Nat.138:1513–41〕 During an outbreak it is difficult to distinguish RRSV yield losses from losses caused by BPH feeding. In addition, BPH also vectors rice grassy stunt virus (RGSV). It is often not possible to quantify how much of the crop loss was due to RRSV, RGSV, or BPH feeding damage.〔Hibino, Rev. Pl. Prot. Res. 12: 98, 1979.〕 Field trials in Indonesia indicate that with a rice ragged stunt incidence of 34–76%, grain yields are only 17–47% of healthy plant yields.〔Palmer, Soepriaman & Mochida, Int. Rice Res. Newsl. 3(3): 15, 1978.〕 RRSV has been reported from China, India, Indonesia, Japan, Malaysia, the Philippines, Sri Lanka, Taiwan, Thailand, and Vietnam.〔Milne, R. G., G. Boccardo, K. C. Ling 1982. Rice Ragged Stunt Virus. (Descriptions of Plant Viruses ). 248, July 1982. American Association of Applied Biologists.〕〔IRRI http://www.knowledgebank.irri.org/factsheetsPDFs/PestManagement_FSRiceRaggedStunt.pdf〕 Presence of RRSV is suspected, but not confirmed, in Cambodia, Lao PDR (Laos), and Myanmar (Burma). There were major outbreaks of RRSV and RGSV in China and Vietnam in 2006–2007.〔Cabunagan and Choi 2009 http://ricehoppers.net/2009/06/why-outbreaks-of-virus-diseases-occurred-in-south-vietnam/〕〔Thomas, Carla S., Noele P. Nelson, Gary C. Jahn, Tianchan Niu, David M. Hartley 2011. (Use of media and public-domain Internet sources for detection and assessment of plant health threats ). Emerging Health Threats Journal 4: 7157 〕 ==External links== *(ICTVdB—The Universal Virus Database: Rice ragged stunt virus ) *(Family Groups—The Baltimore Method ) 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Rice ragged stunt virus」の詳細全文を読む スポンサード リンク
|