Abstract Ramularia leaf spot (RLS) of barley, caused by the fungal pathogen Ramularia collo-cygni, is a significant threat to the viability of spring barley production in Ireland. As a relatively new disease of barley, limited information is available on the development and impact of the disease under Irish conditions. RLS symptoms often only develop after anthesis and the final fungicide application, therefore some decision support is required for growers to be able to make sound integrated pest management (IPM) decisions. In the present study field trials were conducted on spring barley in 2016–2018 to determine if environmental conditions during stem extension, specifically leaf wetness, could be used to aid decisions relating to the intensity of fungicide control required later in the season for the control of RLS. The trials were conducted on four spring barley varieties subjected to one of five fungicide treatments at awn emergence 1) untreated control 2) pyraclostrobin 3) prothioconazole and chlorothalonil 4) decreased/increased rates of prothioconazole and chlrothalonil depending on risk of RLS development and 5) exclusion of prothioconazole or addition of bixafen depending on risk of RLS development. In 2018, although moderate-high levels of disease were predicted, a prolonged dry period post-stem extension resulted in no disease development. In 2016, 2017 moderate levels of disease developed in the trials, with various significant (P

中文翻译：

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爱尔兰生长条件下大麦品种抗性和风险预测控制大麦枝条叶斑病的有效性

摘要 由真菌病原体 Ramularia collo-cygni 引起的大麦 Ramularia 叶斑病 (RLS) 是对爱尔兰春季大麦生产生存能力的重大威胁。作为一种相对较新的大麦病害，关于该病在爱尔兰条件下的发展和影响的信息有限。RLS 症状通常仅在开花和最后施用杀菌剂后出现，因此种植者需要一些决策支持才能做出合理的综合虫害管理 (IPM) 决策。在本研究中，在 2016-2018 年对春大麦进行了田间试验，以确定茎伸展期间的环境条件，特别是叶片湿度，是否可用于帮助决定与本赛季后期所需的杀菌剂控制强度有关的控制RLS。试验是在四个春季大麦品种上进行的，在芒出现时进行了五种杀菌剂处理 1) 未处理的对照 2) 唑菌胺酯 3) 丙硫菌唑和百菌清 4) 丙硫菌唑和百菌清的比率降低/增加，这取决于 RLS 发展的风险和 5)根据 RLS 发展的风险，排除丙硫菌唑或添加联苯吡菌胺。2018 年，尽管预测会出现中高水平的疾病，但茎延长后长时间的干旱期并未导致疾病发展。2016 年、2017 年在试验中发展为中等水平的疾病，具有各种显着性（P 茎伸展后延长的干燥期导致没有疾病发展。2016 年、2017 年在试验中发展为中等水平的疾病，具有各种显着性（P 茎伸展后延长的干燥期导致没有疾病发展。2016 年、2017 年在试验中发展为中等水平的疾病，具有各种显着性（P