Virus‐vector relationships of a planthopper<i>(Peregrinus maidis)‐borne</i>sorghum stripe tenuivirus∗

Abstract

Abstract Sorghum stripe virus (SStV), an isolate of maize stripe tenuivirus on sorghum, is transmitted by a delphacid planthopper (Peregrinus maidis) in a persistent manner throughout its life with intermittent transmission in some individuals. The efficiency of virus transmission by the vector was 42% when individual viruliferous vectors were used per test seedling and 100% with five viruliferous insects. The minimum acquisition and inoculation feeding periods were 4 h and 1 h respectively. Vectors became viruliferous and able to transmit the virus within an 8 days’ incubation period after acquisition of virus from the source plant. The first instar nymphs were found to be the most efficient transmitters (64%) compared with the second to fourth instars (50%) and adults (33%). Fifty‐three percent and 35% of macropterous females and males respectively transmitted the virus, whereas in brachypterous females and males the transmission efficiency was 47% and 27% respectively. Of 595 nymphs obtained from the eggs laid by 10 viruliferous females, only 3% of nymphs transmitted the virus to healthy seedlings. The seedlings Inoculated at the one‐leaf and 10‐leaf stage by viruliferous P. maidis showed 62% and 47% infection and the latent period of virus in the host was 8 and 18 days respectively.