Professor, Laboratory of Plant Virology, South China Agricultural University
Guangzhou 510642, China
The new virus infecting rice discovered in 2001 in Yangxi county, Guangdong province near the coast appear to be spreading in China. The virus disease called the Southern Rice Black Streak Dwarf Virus (SRBSDV) transmitted by the white back planthopper (WBPH) was described by Zhou et al (2008) and Zhang et al (2008). The virus has spread to numerous provinces in Northern Vietnam and in China the virus is found on maize as far north as Shandong province. In total about 300 000 ha rice covering 9 provinces of China have been infected and in Vietnam about 15 000 ha covering 19 provinces were infected. More than 6,500 ha have suffered total crop failure.
Disease symptoms vary depending on the crop ages when infection occurs. When infected in the seedling stage, plants are dwarfed with stiff leaves and can result in death. In the tillering stages, plants are dwarfed and show witches broom symptoms and at the stem elongation stage, infected plants show branching with upward rootlets in the nodes and small waxy swellings or galls on the stems. Infected plants produce abnormal panicles. In the laboratory we found that the virus is mainly transmitted by WBPH. The small brown planthopper (SBPH) was also able to transmit the virus but inefficiently. The brown planthopper (BPH) seems unable to successfully transmit the virus.
The virus also infects maize, Echinochloa, Juncellus and Pennisetum and Chinese sorghum. A recent survey (Zhou et al 2010) showed that infection rates in Guangdong, Guangxi and Hainan had increased. The summer crops transplanted and using hybrid rice varieties were more seriously affected.
Zhang, H.M., Yang, J. and Chen, J.P. 2008. A black-streaked dwarf disease on rice in China is caused by a novel fijivirus. Arch Virol ,153:1893–1898
Zhou GH, Wen JJ, Cai DJ, Li P, Xu DL and Zhang SG. 2008. Southern rice black-streaked dwarf virus: A new proposed Fijivirus species in the family Reoviridae. Chinese Science Bulletin. 53(23):3677-3685.
Zhou GH, Zhang SG, Zou SF, et al., 2010. Occurrence and damage analysis of a new rice dwarf disease caused by Southern rice black-streaked dwarf virus. Plant Protection, 36(2):144-146 (in Chinese).