TRANSMISSION OF PRUNUS NECROTIC RINGSPOT VIRUS TO THREE PEACH CULTIVARS AS MEASURED BY RNA HYBRIDIZATION FOLLOWING IN VITRO MICROGRAFTING

As part of our program to develop transgenic peach cultivars with improved disease resistance, we showed that grafting of in vitro cultured ‘Suncrest’ peach [Prunus persica (L.) Batsch] tips onto decapitated stems of prunus necrotic ringspot virus (PNRSV)-infected ‘Suncrest’ shoot cultures, resulted in consistent transfer of virus across grafts as demonstrated by RNA hybridization analysis, suggesting that such a system could be useful for measuring resistance to PNRSV in peach shoot cultures (Heuss-LaRosa et al., 1995). We have extended these studies to include grafts of ‘Springcrest’ and ‘Nemaguard’ test tips onto ‘Suncrest’ stocks.
RNA hybridization analysis showed that PNRSV persists in shoot cultures for 18 months after initiation from PNRSV-infected ‘Suncrest’ trees and after 16 weeks of treatment at 4°C in the dark, suggesting that a supply of infected shoot cultures could be maintained for repeated use.
Graft success for grafts of ‘Springcrest’ onto ‘Suncrest’ and ‘Nemaguard’ onto ‘Suncrest’, equalled or exceeded success rates for ‘Suncrest’ onto ‘Suncrest’. Virus was transmitted from infected stocks to ‘Suncrest’, ‘Springcrest’, and ‘Nemaguard’ test tips by two weeks in most successful micrografts.
There was no significant difference in the virus concentrations among the three scions at two, four, and six weeks after grafting, suggesting that there is equal efficacy of virus transfer through grafts from ‘Suncrest’ to the three cultivars, and that no differences in resistance to PNRSV exist among these cultivars.

XVII International Symposium Virus and Virus-Like Diseases of Temperate Fruit Crops

K. Heuss, Q. Liu, F.A. Hammerschlag, R.W. Hammond

PNRSV, Prunus persica

https://doi.org/10.17660/ActaHortic.1998.472.22