Forty-eight inbred lines of maize with varying levels of resistance to gray leaf spot (GLS) were artificially inoculated with Cercospora zeina and evaluated to characterize partial disease resistance in maize under field conditions from 2012 to 2014 across 12 environments in western Kenya. Eight measures of disease epidemic—that is, final percent diseased leaf area (FPDLA), standardized area under the disease progress curve (SAUDPC), weighted mean absolute rate of disease increase (ρ), disease severity scale (CDSG), percent diseased leaf area at the inflection point (PDLA_IP), SAUDPC at the inflection point (SAUDPC_IP), time from inoculation to transition of disease progress from the increasing to the decreasing phase of epidemic increase (T_IP), and latent period (LP)—were examined. Inbred lines significantly (P < 0.05) affected all measures of disease epidemic except ρ. However, the proportion of the variation attributed to the analysis of variance model was most strongly associated with SAUDPC (R² = 89.4%). Inbred lines were also most consistently ranked for disease resistance based on SAUDPC. Although SAUDPC was deemed the most useful variable for quantifying partial resistance in the test genotypes, the proportion of the variation in SAUDPC in each plot was most strongly (R² = 93.9%) explained by disease ratings taken between the VT and R4 stages of plant development. Individual disease ratings at the R4 stage of plant development were nearly as effective as SAUDPC in discerning the differential reaction of test genotypes. Thus, GLS rankings of inbred lines based on disease ratings at these plant developmental stages should be useful in prebreeding nurseries and preliminary evaluation trials involving large germplasm populations.

四十八个玉米自交系不同水平的阻力，以灰色叶斑病（GLS）与进行人工接种尾孢泽纳和评估，以在野外条件下在12个环境中西肯尼亚表征局部疾病抗性玉米二〇一二年至2014年。疾病流行的八种度量标准-即最终病叶面积百分比（FPDLA），疾病进展曲线下的标准化面积（SAUDPC），加权平均病害绝对增长率（ρ），疾病严重程度量表（CDSG），病叶百分比疫点的面积（PDLA _IP），病点的SAUDPC（SAUDPC _IP），从接种到疾病进展从流行增加的增加阶段到减少阶段的时间（T _IP）和潜伏期（LP）进行了检查。自交系显着（P <0.05）影响除ρ外的所有疾病流行措施。但是，归因于方差模型分析的变异比例与SAUDPC密切相关（R ² = 89.4％）。自交系的抗病性也最一致。尽管SAUDPC被认为是量化测试基因型中部分抗药性的最有用变量，但每个图中SAUDPC变异的比例最强（R ²= 93.9％）由植物发育的VT和R4阶段之间的疾病评级所解释。在辨别测试基因型的差异反应时，在植物发育的R4阶段，个体疾病等级与SAUDPC几乎一样有效。因此，基于这些植物发育阶段的疾病等级的近交系的GLS等级在育种苗圃和涉及大量种质种群的初步评估试验中应该是有用的。