Pathogenic specificity of Austropuccinia psidii to guava plants

Abstract

The 2-month BEPE internship, to be held at RWTH Aachen University, under the supervisionof Prof. Dr. Ulrich Schaffrath, aims to complement the results obtained by the scholarshipholder in Brazil. The student determined that isolates of Austropuccinia psidii from guava(Psidium guajava), when inoculated onto rose apple plants (Syzygium jambos), an ostensiblysusceptible species to A. psidii, did not form sporulating lesions, indicating high specializationof the fungal isolate to the plant P. guajava. Rose apple plants presented necrotric lesionson the leaf blade, but no sporulation of A. psidii was noticed. To understand the causes ofthe necrotic reactions displayed in rose apple, after inoculation with the isolate of A.psidii from guava, the student will use confocal microscopy techniques. Prof. Dr. Schaffathis expert in histological and molecular studies of non-host plant species to pathogens, withextensive experience in rusts. His laboratory has staining protocols for these fungi, whichfacilitates the use of the technique to verify the infection and colonization of pathogens inleaves. Many of his project were done on soybean or grapevine rust. This research group ispart of the thematic project 2019/13191-5, under the coordination of Prof. Lilian Amorim, towhich this scholarship is linked. The internship abroad aims to train the student in confocalmicrocopy techniques, with samples of experiments carried out in Brazil but analyzed inGermany.