Biovar-specific and broad-spectrum sources of resistance to bacterial wilt (Ralstonia solanacearum) in Capsicum
Carlos A Lopes, and Leonardo S Boiteux
No report has so far investigated either the biovar-specific or broad-spectrum reaction to Ralstonia solanacearum (RS) in Capsicum germplasm. Twenty-three accessions described as resistant to RS in different countries were challenged with Brazilian biovar I and biovar III isolates. Differences were observed among accessions and within biovar III isolates. In addition, isolates of biovar III were more aggressive than biovar I, reinforcing field observations which indicated that RS biovar III is predominant and more virulent and aggressive than biovar I isolates on Capsicum. Accessions previously reported as extremely resistant to RS in Asia exhibited slight wilt symptoms when challenged with Brazilian isolates. However, the high resistance levels in the inbred lines ‘MC-4’, ‘PBC 631’, ‘PBC 066’, ‘PBC 1347’, and ‘PBC 473’ make these accessions suitable for breeding programs aiming to develop pungent and/or sweet cultivars with a stable, broad-spectrum RS-resistance.