The fall armyworm (Spodoptera frugiperda, Lepidoptera: Noctuidae), which is native to the Americas, has recently invaded Africa and Asia. There, it has become a major pest of maize (Zea mays). The variety of methods used to assess feeding damage caused by its caterpillars makes it difficult to compare studies. In this paper, we aim at determining which leaf damage rating scales for fall armyworm are most consistently used for which purposes, might provide most possibilities for statistical analyses, and would be an acceptable compromise between detail and workload. We first conducted a literature review and then validated the most common scales under field and laboratory conditions. Common leaf damage scales are the nominal “yes-no damage scale” that only assesses damage incidence, as well as difficult-to-analyse ordinal scales which combine incidence and severity information such as the “Simple 1 to 5 whole plant damage scale”, “Davis’ 0 to 9 whorl & furl damage scale”, or “Williams’ 0 to 9 whole plant damage scale”. These scales have been adapted many times, are sometimes used incorrectly, or were wrongly cited. We therefore propose simplifications of some of these scales as well as a novel “0.0 to 4.0 fall armyworm leaf damage index” which improves precision and possibilities for parametric data analyses. We argue that the choice of a scale to use should depend on the desired level of detail, type of data analyses envisioned, and manageable time investment.

秋天的夜蛾（Spodoptera frugiperda，鳞翅目：夜蛾科），原产于美洲，最近入侵了非洲和亚洲。在那儿，它已经成为玉米的主要害虫（玉米（Zea mays））。用于评估由其毛虫引起的进食损害的方法多种多样，因此很难进行比较研究。在本文中，我们旨在确定最适合用于哪个目的的秋夜蛾叶片损伤等级量表，可能为统计分析提供最多的可能性，并且是细节和工作量之间可接受的折衷方案。我们首先进行了文献综述，然后验证了在野外和实验室条件下最常见的量表。常见的叶片损害量表是名义上的“是-没有损害量表”，它仅评估损害发生率，以及难以分析的顺序量表，其结合了发生率和严重性信息，例如“简单的1至5个整个植物的损害量表”， “戴维斯的0至9轮生皮破坏度标度”，或“威廉姆斯的0至9整个植物的损害度标度”。这些量表已经过多次修改，有时使用不当或被错误引用。因此，我们建议简化其中一些比例，以及提出一种新颖的“ 0.0至4.0秋季粘虫叶损伤指数”，以提高精度和参数数据分析的可能性。我们认为，使用规模的选择应取决于所需的详细程度，预期的数据分析类型以及可管理的时间投入。