Candidatus Liberibacter solanacearum haplotype B (CLsoB) is an economically important pathogen of tomato (Solanum lycopersicum L.) crops in New Zealand and Central and North America. Currently, resistant cultivars of tomato are not available as a management tactic because breeding programmes lack sources of resistance. Therefore, the objective of this study was to identify sources of resistance in tomato to CLsoB. Forty‐six landraces of tomato were collected from several states in Mexico and were inoculated with CLsoB using 20 infested adults of Bactericera cockerelli per plant. Two assays were done over two years under greenhouse conditions. In the first trial, landraces FC22 and FC44 showed a significantly higher proportion of resistant plants, less symptom severity and longer incubation time compared with the other forty‐four landraces and two susceptible cultivars. In the second assay, resistance to CLsoB of the landraces FC22 and FC44 was confirmed because they had again significantly greater numbers of resistant plants, less symptom severity, relative lower CLsoB titers and longer incubation time relative to the other genotypes. All plants considered resistant from both assays had DNA of CLsoB. Results indicate that all resistant plants from these landraces are promising sources for the development of tomato cultivars with resistance to CLsoB.

中文翻译：

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墨西哥番茄本地种对B型念珠菌的抗性

暂定Liberibacter菌单倍型B（CLsoB）是番茄的一种重要的经济病原菌（番茄L.）作物在新西兰和中美洲和北美洲。目前，由于育种计划缺乏抗性来源，因此无法将抗性番茄品种作为管理策略。因此，本研究的目的是确定番茄对CLsoB的抗性来源。番茄的四十六个地方品种从几个州位于墨西哥收集并接种CLsoB使用20名出没的成年人Bactericera cockerelli每个植物。在温室条件下进行了两年的两次测定。在第一个试验中，与其他44个地方品种和两个易感品种相比，地方品种FC22和FC44表现出显着更高的抗性植物比例，症状轻度和较长的潜伏时间。在第二种测定法中，确认了地方品种FC22和FC44对CLsoB的抗性，因为相对于其他基因型，它们再次具有显着更多的抗性植物数量，症状严重程度较低，相对较低的CLsoB滴度和较长的孵育时间。两种测定均被视为抗性的所有植物均具有CLsoB DNA。结果表明，来自这些地方种的所有抗性植物都是发展对CLsoB具有抗性的番茄品种的有前途的来源。