Assessment of resistance to Rhizoctonia solani in tall fescue based on disease progress and crop recovery

Cultivars of turf-type tall fescue were assessed, in a controlled environment and in the field, for resistance to Rhizoctonia solani, the cause of brown patch or Rhizoctonia blight. Assessments were based on areas under disease progress curves (AUDPC) and AUDPC plus areas under crop recovery curves (AUCRC). Values of AUDPC were calculated from estimates of percent necrotic foliage during epidemics of brown patch with durations of 3-8 wk in the field or 8 days in a growth chamber. Values of AUCRC were calculated from postepidemic estimates of percent necrotic foliage over 4 wk in a greenhouse or 4-8 wk in the field (.)