S01 - Session P5 - Preliminary evaluation of Bulgarian pepper landraces for resistance to four viruses

Authors: Gancho Pasev *, Vesela Radeva-Ivanova, Veronika Pashkoulova, Amol Nankar, Dimitrina Kostova

The Balkan peninsula is considered as a secondary center of biodiversity of pepper ( Capsicum annuum L.) because of its conducive climate and edaphologic conditions. Bulgaria, as part of the region, has a long tradition in pepper cultivation. Very often, the pepper production is threatened by harmful pathogens, including viruses, which cause heavy losses in terms of the quantity and quality of the crop. There is a great need of reliable sources of resistance to the most widely spread viruses, such as Cucumber mosaic virus (CMV), Tobacco mosaic virus (TMV), Pepper mild mottle virus (PMMoV) and Tomato spotted wilt virus (TSWV). The aim of this study was to evaluate the resistance to these viruses in 16 pepper landraces collected from small private gardens in central, northern and western Bulgaria. The accessions were tested by detached leaf test (DLT) with local isolates of TMV, PMMoV (P1.2) and TSWV. The CMV screenings were performed by direct inoculation with two isolates (PV-0418, DSMZ and L-BG, local one with satellite RNA), each on a different set of plants. The resistance in CMV infectious trials was monitored by visual inspection of symptoms and ELISA on inoculated and upper leaves at least one month after inoculation. For tobamoviruses and TSWV the inoculated detached leaves were observed for necrotic lesions. Resistance to both strains of CMV and TMV was established in one accession. Another three accessions were resistant to L-BG isolate (CMV) and TMV. The remaining 9 accessions showed resistance only to TMV. All of the accessions were susceptible to PMMoV and TSWV. This study showed that local well-adapted pepper forms from Bulgaria might serve as a source of resistance to economically important viruses.