The objective of this work was to identify resistance sources to leaf rust in peach tree. Three evaluations of leaf rust incidence and severity were performed in 1/15, 2/14 and 03/24 of 2005 in 17 genotypes; severity was evaluated in 2/23/2006, in 12 genotypes and in the 17 ones previously evaluated; incidence, severity and defoliation were evaluated in 1/28/2008, in the 29 evaluated genotypes and in 'Conserva 803'; in 2/3/2008, lesions per leaf were determined in 12 genotypes. Analysis of variance was performed for incidence, severity, and lesions per leaf, for each year, and means were compared by Scott-Knott test. Pearson's correlation analyses were accomplished for incidence, severity, defoliation and lesion per leaf (2008). Data for incidence, severity and defoliation (1/28/2008) and severity (2/23/2006) were submitted to multivariate analysis. 'Olímpia' and 'Cascata 1063' showed acceptable levels of resistance to leaf rust; no immunity to leaf rust was detected; however, differential efficiency of infection among genotypes was observed, which indicates that the resistance could be horizontal; the number of lesions per leaf could be used to classify peach genotypes reaction to leaf rust.
Prunus persica; Tranzschelia discolor; disease resistance
