Sayama H.,Nippon Del Monte Co. R and D |
Sayama H.,Kikkoman Co. R and D |
Takayanagi N.,Nippon Del Monte Co. R and D |
Yamada M.,Nippon Del Monte Co. R and D |
And 5 more authors.
Acta Horticulturae | Year: 2015
In gentian (Gentiana scabra var. buergeri) plants pre-inoculated with satellite RNA (SatRNA) containing attenuated CMV strains, double stranded satellite RNA (dsSatRNA) was detected only in inoculated leaves and no dsSatRNA was observed in the upper leaves. However, upon challenge-inoculation with virulent CMV, accumulation of dsSatRNA in upper leaves and suppression of systemic movement of virulent CMV to upper leaves were observed in pre-inoculated gentian plants, and the symptoms observed in the upper leaves were milder than those in non preinoculated plants. Those results indicated that accumulation of dsSatRNA and less virulent CMV observed in the upper leaves of pre-inoculated gentian plants were triggered by virulent CMV infection and resulted in milder symptoms in the upper leaves. A relatively high ratio of surviving plants after dormancy was observed in plants infected with the SatRNA-containing attenuated CMV strain and then infected with virulent CMV compared to plants infected with virulent CMV alone. In addition, when new shoots sprouted from the roots after dormancy, dsSatRNA was still detected in some plants infected with the SatRNA-containing attenuated CMV strain and then infected with virulent CMV. These results collectively may explain why protective effects lasted for several years in the field and high cut flower productions maintained in gentian plants pre-inoculated with SatRNA-containing attenuated CMV strains.