Nicotiana africana carries resistance to Potato Virus Y, including a highly virulent necrotic strain PVYNZ. The species was hybridized with several flue-cured cultivars of N. tabacum , both susceptible and tolerant to the pathogen. An attempt was made to study the expression of resistance to PVY in hybrids of different genomic makeup including amphihaploids, amphidiploids, sesquidiploids and post-sesquidiploids and over different N. tabacum background. In the majority of amphihaploids, amphidiploids and sesquidiploids the full resistance of N. africana parent was recovered, regardless of the PVY response of N. tabacum parent. A very small percentage of amphihaploid, amphidiploid and sesquidiploid plants were found to be symptomless carriers of the virus. In the postsesquidiploid generation full resistance response was found in ca. 6% of the segregants indicating a transmission rate that may be considered reasonably good for a Nicotiana interspecific hybrid. Full expression of PVY resistance in heterozygous/hemizygous condition together with satisfactory level of transmission to segregating generations make N. africana a promising source of PVY resistance in tobacco improvement programs.