Downy mildew caused by Peronospora variabilis is a major fungal disease limiting yield of quinoa (Chenopodium quinoa) around the world. Existing quinoa cultivars do not have adequate levels of resistance to the disease. In the present study, 165 quinoa accessions were screened for resistance to the disease in two consecutive years. Disease ratings were performed by using a three-leaf scoring technique. In 2018, of 70 quinoa accessions, 47.14% were moderately resistant and 18.57% were highly resistant. However, in 2019, of 95 accessions, 44.21% showed moderately resistant reaction and 26.31% highly resistant reaction to the disease. The average of AUDPC (area under disease progress curve) of all the accessions was 1293.42 in 2018, and 931.68 in 2019. The disease caused significant (P < 0.01) cumulative defoliations in susceptible accessions. AUDPC was positively correlated (r = 0.796 in 2018, r = 0.896 in 2019) with defoliation rate and negatively correlated (r = –0.834 in 2018, r = –0.599 in 2019) with plant height. There were also negative correlations (r = –0.755 in 2018, r = –0.580 in 2019) between defoliation rate and plant height. The study not only revealed resistant germplasm but also showed the importance of screening downy mildew resistance by comparing disease-related agronomic characteristics.

由变异霜霉病引起的霜霉病是世界范围内限制藜（Chenopodium quinoa）产量的主要真菌病害。现有的藜麦品种对该病的抵抗力不足。在本研究中，连续两年对 165 份藜麦种质进行了抗病性筛选。通过使用三叶评分技术进行疾病评级。2018 年，在 70 份藜麦种质中，47.14% 为中等抗性，18.57% 为高度抗性。然而，2019年95份材料中，44.21%对该病呈中度抗性反应，26.31%表现出高度抗性反应。2018 年所有材料的 AUDPC（疾病进展曲线下面积）平均值为 1293.42，2019 年为 931.68。P < 0.01) 易感种质的累积落叶。AUDPC呈正相关（[R = 0.796在2018年，- [R在2019 = 0.896）与落叶率和负相关（ř在2018年，= -0.834 - [R = -0.599在2019）与植物高度。也有（负相关[R = -0.755在2018年，- [R = -0.580 2019年）落叶率和株高之间。该研究不仅揭示了抗性种质，而且还通过比较与疾病相关的农艺学特征显示了筛选霜霉病抗性的重要性。