dc.description.abstract | Ralstonia solanacearum is a soil borne bacterium which affects more than 450 plant species
including a wide range of crop plants, ornamentals and weeds. This bacterium is causing
bacterial wilt disease which leads to severe economic losses. On potato, disease is known
as brown rot. Even though this phytopathogen originates from tropic, subtropics and warm
temperate regions, in recent years cold-adapted strains dramatically enhanced the threat
of European potato crops, including Serbia. R. solanacearum is at A2 list of quarantine plant
pathogens in Europe. During six year period (2013-2018), isolates from diseased potato
tubers were collected, identified using Multilocus sequence analysis (MLSA) and checked
for certain phylotype affiliation. DNA from the obtained isolates was amplified using seven
housekeeping genes (adk, fliC, gapA, gdhA, gyrB, hrpB, ppsA) and sequenced. Phylogenetic
analysis was performed with concatenated sequences of all tested isolates, and compared
with the most similar R. solanacearum strains from PAMDB database. All Serbian isolates
were identified as R. solanacearum using PAMDB BLAST. Neighbor-joining phylogenetic
analysis placed tested isolates in the same cluster with R. solanacearum strains belonging
to race 3, biovar 2, and phylotype II obtained from PAMDB. Although, bacterial wilt caused
by this plant pathogenic bacteria is appearing in different locations and on different potato
cultivars in Serbia it remained genetically homogenous. Currently, R. solanacearum is a
quarantine bacteria occurring only on potato in our country, but considering its wide host
range, there is a possibility of it causing disease on other significant crops with devastating
consequences. Therefore, its fast and accurate identification and mapping is of main interest
for stopping the disease spread. | sr |