Phytopathology. 1999 Feb;89(2):131-5. doi: 10.1094/PHYTO.1999.89.2.131.
ABSTRACT The relationship between leaf-associated population sizes of Xanthomonas translucens pv. translucens on asymptomatic leaves and subsequent bacterial leaf streak (BLS) severity was investigated. In three experiments, X. translucens pv. translucens was spray-inoculated onto 10-day-old wheat seedlings over a range of inoculum densities (10(4), 10(5), 10(6), 10(7), and 10(8) CFU/ml). Lesions developed most rapidly on plants inoculated with higher densities of X. translucens pv. translucens. Leaf-associated pathogen population sizes recovered 48 h after inoculation were highly predictive of BLS severity 7 days after inoculation (R(2) = 0.970, P < 0.0001). The relationship between pathogen population size on leaves and subsequent BLS severity was best described by the logistic model. Leaf-associated X. translucens pv. translucens population size and BLS severity from a particular pathogen inoculum density often varied among experiments; however, the disease severity level caused by a particular leaf-associated X. translucens pv. translucens population size was not significantly different among experiments. Biological and disease control implications of the X. translucens pv. translucens population size-BLS severity relationship are discussed.
摘要 本研究调查了无症状叶片上黄单胞菌野油菜致病变种（Xanthomonas translucens pv. translucens）的叶部定殖群体大小与随后细菌性条斑病（BLS）严重程度之间的关系。在三个实验中，将 X. translucens pv. translucens 以不同的接种浓度（10^4、10^5、10^6、10^7 和 10^8 CFU/ml）通过喷雾接种于 10 天大的小麦幼苗上。接种高浓度 X. translucens pv. translucens 的植株上病斑发展最快。接种后 48 小时回收的叶片相关病原体种群大小与接种后 7 天的 BLS 严重程度高度相关（R^2 = 0.970，P < 0.0001）。叶片上病原菌种群大小与随后 BLS 严重程度之间的关系最适合用逻辑模型来描述。来自特定病原体接种密度的叶片相关 X. translucens pv. translucens 种群大小和 BLS 严重程度在不同实验中通常存在差异；然而，特定叶片相关 X. translucens pv. translucens 种群大小引起的疾病严重程度水平在不同实验中没有显著差异。讨论了 X. translucens pv. translucens 种群大小与 BLS 严重程度之间关系的生物学和疾病控制意义。
