The witches' broom is one of the most important diseases that affect the cocoa tree (Theobroma cacao), caused by the basidiomycete Moniliophthora perniciosa and characterized by symptoms of swelling and induction of shoots on infected branches. The Solanum lycopersicum (Syn. Lycopersicon esculentum), also host of the fungus M. perniciosa, has a miniature cultivar 'Micro-Tom' (MT), which proved to be appropriate genetic model for studying the interaction with this pathogen, with characteristic symptoms of hypertrophy, hyperplasia and formation of brooms. It is known that the development of symptoms of witches and defense response of plants are related to signaling by phytohormones, which is extremely important to understand this complex hormonal network in the model already established for M. perniciosa. Thus, in this project, MT, transgenic and mutants plants with alterations in the biosynthetic/perception pathway of hormones salicylic acid (SA), jasmonic acid (JA) and ethylene (ET) will be challenged with M. perniciosa to determine the disease incidence and analyzed by RT-qPCR for marker genes associated with these hormones. The transcriptome of plants inoculated with the fungus of biotype-S and -C will also be revealed by sequencing by RNA-Seq, searching for genes related to phytohormones. Furthermore, assessments will be made through metabolomics by nuclear magnetic resonance (NMR) and gas (GC) and liquid (LC) chromatography coupled to mass spectrometry (MS) in MT, hormonal and mutants plants and transgenic inoculated with biotypes -S and C, in order to observe the metabolic profile in different types of interaction (compatible and incompatible) with the fungus M. perniciosa.
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