MONITORING OF POTATO FIELDS TO PRESENCE OF RALSTONIA SOLANACEARUM

Abstract

BACKGROUNDS: Ralstonia solanacearum race 3 biovar 2 is one of the most important plant pathogenic bacteria because of its persistence, wide host range and widespread. It´s causing bacterial wilt of over 250 plant species, including many cultivated crops (potato, tomato, eggplant, geranium, ginger, banana, etc.) and brown rot of potato. OBJECTIVES: The aim of this study was to determine presence of R. solanacearum based on several years monitoring of potato tubers. METHODS: During four-year period (2013-2016), 98 samples of potato tubers (11 cultivars), from 13 localities in Bačka and 1 in Podunavlje region were examined. Isolation from potato tubers with brown rot symptom was performed on semi-selective SMSA medium. PCR method using Ps-1/Ps-2 and OLY1/Y2 primers and immunofluorescence were used to detect presence of R. solanacearum. Pathogenicity was tested on young tomato plants. RESULTS: In 2013, R. solanacearum was detected in 1 sample of potato tuber (Lady Claire) from Srpski Miletić; in 2015 in 2 (Crisps4all, VR 808) from Srpski Miletić and 1 (VR 808) from Stapar; during 2016 in 2 (Crisps4all, Brooke) from Srpski Miletić, 2 (Lady Claire, VR 808) from Stapar, 2 (Lady Claire, Pirol) from Sombor and 1 (Panda) from Boleč. Milky-white, with pink to red centre, flat, irregular, fluidal colonies formed after 3-4 days of incubation on SMSA medium. A 553 bp and 288 bp fragments of 65 representative isolates were amplified using Ps-1/Ps-2 and OLY1/Y2 primer pairs, respectively. IF test proved presence of fluorescent bacterial cells. All strains caused wilting on tomato seedlings four days after inoculation. CONCLUSIONS: The results of this study detected presence of R. solanacearum on 11 potato samples isolated from four locations during period from 2013-2016.