A survey of Nicotiana germplasm for resistance to Tomato spotted wilt virus (TSWV)

The reaction to Tomato spotted wilt virus (TSWV) was evaluated in 94 accessions of Nicotiana, originating from the Institute of Soil Science and Plant Cultivation tobacco germplasm collection in Pu?awy, Poland. Tests for resistance were conducted under greenhouse conditions using single TSWV isolate collected from tobacco plantation in Lublin district, Poland. The presence of the virus was verified using DAS-ELISA. SCAR markers associated with TSWV resistance gene were applied. The members of the section Alatae, the genus Nicotiana: N. alata, N. forgetiana, and Nicotiana x sanderae as well as N. tabacum cultivars: ‘Polalta’ and ‘Wiktoria’ with the TSWV resistance gene introduced from N. alata, displayed the hypersensitive reaction (HR) against TSWV (grade 0 on symptom intensity scale). In some of those accessions, the virus spread from the initially infected areas eliciting systemic hypersensitive reaction (SHR). Five accessions of N. alata and three of Nicotiana x sanderae were composed of 6.3–50.0 % of plants in which SHR symptoms appeared. In all of N. forgetiana plants HR reaction was followed by systemic infection (SHR). In N. tabacum ‘Wiktoria’ 21.1 % of plants showed HR reaction, while the remaining were susceptible (S). All of the genotypes which responded with HR or SHR reaction to TSWV infection demonstrated the presence of SCAR markers linked to the resistance gene. The remaining eighty tested accessions were identified as being susceptible upon exposure to TSWV.