Preliminary evaluation of Bulgarian pepper landraces for resistance to four viruses

The Balkan peninsula is considered a secondary centre of biodiversity of pepper (Capsicum annuum L.) due to congenial climate and edaphologic conditions.
Bulgaria, as part of the region, has a long-lasting tradition in pepper cultivation.
Very often, the pepper production is threatened by dangerous pathogens, including viruses, which cause heavy losses in terms of both quantity and quality of the yield.
There is a great need for reliable sources of resistance to the 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.
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 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 observed in one accession.
Another three accessions were resistant to the 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. Our study showed that local, well-adapted pepper forms from Bulgaria might serve as a source of resistance to economically important viruses.

XXXI International Horticultural Congress (IHC2022): International Symposium on Breeding and Effective Use of Biotechnology and Molecular Tools in Horticultural Crops

G. Pasev, V. Radeva-Ivanova, V. Pashkoulova, A. Nankar, D. Kostova

Capsicum, accessions, viruses

https://doi.org/10.17660/ActaHortic.2023.1362.40