Identifying possible sources of genetic variability is significant in the case of Citrus dwarfing viroid (CDVd) which has been proposed as a dwarfing agent for highdensity citrus plantings. In order to mimic the natural conditions of the field, a natural CDVd isolate (CMC) was used as an inoculum source for long-term and short-term bioassays in different citrus host species including both rootstock and grafted citrus species. Characterization of progenies (derived populations) indicates that the genetic stability of CDVd was high in certain hosts (Trifoliate orange, Troyer citrange, Etrog citron, Navelina sweet orange), which preserve viroid populations similar to the original CMC isolate even after 25 years. By contrast, CDVd variant populations in Interdonato lemon and Volkamer lemon were completely different to those in the inoculated sources, highlighting how influential the host is on the genetic variability of CDVd populations. The results allow to preliminarily discuss the implications for risk assessment of the use of CDVd as a dwarfing agent even if specific experiments for the genetic and pathogenetic evolution of single variant are in progress.
Host effects on the progeny of Citrus dwarfing viroid
Di Serio F
2013
Abstract
Identifying possible sources of genetic variability is significant in the case of Citrus dwarfing viroid (CDVd) which has been proposed as a dwarfing agent for highdensity citrus plantings. In order to mimic the natural conditions of the field, a natural CDVd isolate (CMC) was used as an inoculum source for long-term and short-term bioassays in different citrus host species including both rootstock and grafted citrus species. Characterization of progenies (derived populations) indicates that the genetic stability of CDVd was high in certain hosts (Trifoliate orange, Troyer citrange, Etrog citron, Navelina sweet orange), which preserve viroid populations similar to the original CMC isolate even after 25 years. By contrast, CDVd variant populations in Interdonato lemon and Volkamer lemon were completely different to those in the inoculated sources, highlighting how influential the host is on the genetic variability of CDVd populations. The results allow to preliminarily discuss the implications for risk assessment of the use of CDVd as a dwarfing agent even if specific experiments for the genetic and pathogenetic evolution of single variant are in progress.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
