Apple blotch (Marssonina coronaria) is a foliar disease of increasing importance globally. Methods to quantify the disease and knowledge about epidemiology are required for new studies on the disease. The objectives of this study were to develop a standard area diagram set (SADs) to assess apple blotch severity and to describe the temporal progress of the disease under field conditions on older and younger leaves of two apple cultivars. For the development of SADs, symptomatic leaves were collected and scanned to obtain the actual severity. Based on the pattern of the disease, a SADs was elaborated and validated. Leaf severities were estimated without and with SADs by 12 raters to validate the tool. After validation, the SADs was used to assess apple blotch in older and younger leaves of selected shoots during the vegetative cycle of cvs. Eva and Gala. SADs severities ranged from 0.2 to 96%. Accuracy, precision, and reliability of the estimates were significantly improved when the SADs was used. In the field, the onset of apple blotch was in late spring and greater increases in severity occurred during summer. Rates of disease progress ranged from 0.09 to 0.13. Epidemics were different in older and younger leaves at the end of the apple vegetative cycle for both cultivars tested. Our work provided a tool for apple blotch quantification and described the disease progress curve under subtropical conditions, which can contribute as basis for future studies.

苹果斑点（Marssonina coronaria）是全球范围内越来越重要的叶面疾病。对该疾病进行新的研究需要量化疾病的方法和有关流行病学的知识。这项研究的目的是开发一个标准面积图集（SAD），以评估苹果斑点严重程度，并描述田间条件下两个苹果品种的老叶和幼叶上该病的暂时进展。为了发展SAD，收集有症状的叶子并扫描以获得实际的严重程度。根据疾病的模式，对SAD进行了详细的设计和验证。由12位评估者评估不使用SAD和使用SAD时的叶片强度，以验证该工具。验证后，将SAD用于评估cvs的营养周期中所选芽的老枝和幼枝中的苹果斑点。伊娃和联欢晚会。SAD的严重程度在0.2％到96％之间。使用SAD时，估计的准确性，准确性和可靠性得到了显着提高。在田间，苹果斑点在春季晚些时候开始发作，严重程度在夏季期间更大。疾病进展的速度为0.09至0.13。在两个苹果品种的营养生长周期结束时，老叶和幼叶的流行情况均不同。我们的工作提供了用于苹果斑点定量的工具，并描述了亚热带条件下的疾病进展曲线，这可以为将来的研究奠定基础。疾病进展的速度为0.09至0.13。在两个苹果品种的营养生长周期结束时，老叶和幼叶的流行情况均不同。我们的工作提供了用于苹果斑点定量的工具，并描述了亚热带条件下的疾病进展曲线，这可以为将来的研究奠定基础。疾病进展的速度为0.09至0.13。在两个苹果品种的营养生长周期结束时，老叶和幼叶的流行情况均不同。我们的工作提供了用于苹果斑点定量的工具，并描述了亚热带条件下的疾病进展曲线，这可以为将来的研究奠定基础。