One of the priorities at this moment of the apple tree genetic breeding program in the south of Brazil is the obtainment of resistant cultures to the Gala Leaf Spot (MFG) disease. This illness is caused mainly by the fungus Colletotrichum gloeosporioides, what has been causing great loss in the apple production. To solve this problem, the first step is to select the resistant germoplasm, that will supply the resistant genes. In this research we used 3 isolates of C. gloeosporioides from different apple producer locations, and 245 samples belonging to the Active Germoplasm Bank Apple Tree from the Experimental station of EPAGRI in Caçador, Santa Catarina. For the inoculation of the leaf tissue, the concentration of the conidia was adjusted to 10³ spore/ml. After 72 hours of incubation at 25ºC, were evaluated for the presence and absence of the symptom and its severity, through the diagrammatic scale. The experimental delineation was completely by randomized with 3 repetitions. The severity differences among the samples were tested through the Anova non-parametric Kruskal Wallis test. Among the tested samples, 185 were resistant and 32 susceptible. From those susceptible, there was not a difference in the severity degree of the MFG attack. The data obtained in this study can help in the choice of resistant samples, that could be used as a parentage in the genetic breeding programs of the apple tree, to obtain the resistance to this disease.
Malus domestica Borkh; inoculation; sample; resistant; susceptible; breeding
