Virus-induced gene silencing in Prunus fruit tree species with the Apple latent spherical virus vector

Virus-induced gene silencing (VIGS) has been used as a rapid and effective tool for functional analysis of genes in various plants, including woody fruit tree species. In this study, we attempted to develop a VIGS-based gene evaluation system for seven Prunus species, including apricot (P. armeniaca L.), sweet cherry (P. avium L.), almond [P. dulcis (Mill.) D. A. Webb.], peach (P. persica Batsch), Japanese apricot (P. mume Siebold & Zucc.), Japanese plum (P. salicina Lindl.), and European plum (P. domestica L.), with the Apple latent spherical virus (ALSV) vectors. ALSV vectors carrying part of the apricot PHYTOENE DESATURASE (PDS) gene sequence were amplified in Nicotiana benthamiana, and inoculated into the cotyledons of Prunus seedlings by particle bombardment. Typical PDS-silenced phenotypes, characterized by uniform discoloration of the upper leaves, were observed in sweet cherry and some cultivars of apricot and almond several weeks after inoculation. In contrast, attempted ALSV infections of Japanese apricot, Japanese plum, European plum, and the other cultivars of apricot and almond were unsuccessful. Furthermore, although the infection rate of ALSV in peach was high, severe viral infection symptoms were observed in the infected leaves. These results collectively suggested that the efficiency of ALSV infection and VIGS could vary depending on species and/or cultivar in Prunus. The possible use of the ALSV-mediated VIGS system for functional analysis of genes in Prunus is discussed.

研究紹介 (Research Report)