The Efficiency of Southern rice black-streaked dwarf virus Transmission by the Vector Sogatella furcifera to Different Host Plant Species
Southern rice black-streaked dwarf disease is a new rice disease that severely affects rice production in South China. To understand transmission capacity of the vector Sogatella furcifera to Southern rice black-streaked dwarf virus (SRBSDV) among different host plant species, potential host plants of SRBSDV collected from the diseased rice field and/or adjacent to the field in Hunan Province, China, were determined by RT-PCR, and the transmission rates of SRBSDV by S. furcifera among different host plant species were investigated. The results showed that host plants of SRBSDV in the rice fields were five of family Gramineae (Oryza sativa, Echinochloa crusgalli, Zea mays, Paspalum distichum, Alopecurus aequali) and two of family Cyperaceae (Juncellus serotinus and Cyperus difformis). S. furcifera could not transmit SRBSDV between gramineous plants and cyperaceous plants, and could not transmit SRBSDV between the gramineous plants, J. serotinus and C. difformis as well. However, SRBSDV could be transmitted by S. furcifera within gramineous plants. S. furcifera could transmit SRBSDV between interspecies among three species plants (O. sativa, E. crusgalli and Z. mays), and between P. distichum and A. aequali. At 15, 20, 25, 30, and 35°C, both macropterous and brachypterous adult of S. furcifera could transmit SRBSDV from the plants (e.g., E. crusgalli, Z. mays and O. sativa) infected with SRBSDV to rice seedlings. The transmission rates were first increased and then decreased with the increase of temperature. Macropterous adults transmitted SRBSDV from the viruliferous E. crusgalli, Z. may and rice plants to the healthy rice seedlings, and the infected rates of rice seedlings were 26.2, 18.8 and 23.7% at 15°C, 56.6, 64.6 and 53.6% at 25°C, and was 11.2, 10.2 and 7.3% at 35°C, respectively. Transmission capacity of brachypterous adults was significantly higher than that of macropterous adults at 15, 20 and 25°C (P<0.05), while transmission capacity of brachypterous adults was relatively lower compared with that of macropterous ones at 35°C. These results offer evidence on the transmission of SRBSDV via the vector S. furcifer among different host plants, which can be helpful to control Southern rice black-streaked dwarf disease by the appropriate cultural measures in South China.