E. Sivamani et al., Rice plant (Oryza sativa L.) containing Rice tungro spherical virus (RTSV)coat protein transgenes are resistant to virus infection, MOL BREED, 5(2), 1999, pp. 177-185
The coat protein (CP) genes CP1, CP2 and CP3 of Rice tungro spherical virus
(RTSV) were introduced individually or together to indica and/or japonica
rice cells by particle bombardment and transgenic plants were produced. Pla
nts derived from selfed progeny of the primary transformants were subjected
to virus inoculation via leafhoppers, the natural vector of the virus. Six
teen out of the nineteen selected transgenic plant lines, as well as their
R1, R2 and/or R3 progeny that contained the target gene, accumulated transc
ripts of the chimeric CP gene(s) by RNA blot analysis. We obtained evidence
of moderate levels of protection to RTSV infection, ranging from 17% to 73
% of seedlings that escaped infection and a significant delay of virus repl
ication under greenhouse conditions in plant lines that expressed the RTSV-
CP1, CP2 and CP3 genes singly or together. There was not an additive effect
on resistance when more than one CP gene is expressed. This study is the f
irst to report pathogen-derived resistance to infection by RTSV, one of the
two viruses that are involved in rice tungro disease. It is also the first
example of CP-mediated protection against a virus that contains more than
one CP gene from the same virus.