The rust, caused by the fungi Puccinia psidii, is one of the most frequent diseases on eucalyptus forests in Brazil. Currently, the use of resistant eucalyptus clones is the most important strategy to control this disease on the field. In order to select a resistant clone is essential to inoculated and to evaluate the phenotypic of various genetic materials. This procedure is time and resource consuming. To improve this step of the breeding program, the present work aimed at evaluating the resistance during the micro propagation of eucalyptus clones. Therefore, six clones were micro propagated on MS medium adjusted to promote the multiplication, growing and rooting. After 60 days of incubation, the explants were inoculated with the pathogen spores adjusting to 2x10(4) urediniospores mL-1. The explants were incubated at 24 ± 2 ºC, with light photoperiod of 14 h under intensity of 20 ∝mol.s-1.m-2. After 7, 11, and 14 days of incubation, the disease incidence was evaluated. It was found a high correlation between the results obtained with the protocol developed in this work and the results of the standard rust inoculation proceeding. It was possible to conclude that this new proceeding allows fast and precise evaluation of several eucalyptus clones at the same time.
Puccinia psidii; Resistance; Genetic breeding; Indexing; Disease control
