Evaluation of effector interaction Phyllosticta citricicarpa and sweet orange (Citrus sinensis (L.) Osb.)

Abstract

Citrus is one of the most important crops in the world and Brazil stands out as the largest producer, accounting for over 60% of world production of orange juice. Nevertheless, this sector has faced problems mainly due to the large number of pests and diseases. These include the citrus black spot (CBS), caused by the fungus Phyllosticta citricicarpa, being responsible for huge losses to the Brazilian production, besides being considered A1 quarantine by the European Union and A2 quarantine by the United States. Almost all varieties of citrus are susceptible to this disease, which affect significantly the appearance of the fruit, invalidating its domestic market and export. Also causes early maturing and premature fruit drop and a significant loss of production. Despite the importance of this disease, currently there are only few studies on the genetics of P. citricicarpa. However, our group performed the genome sequence of this fungus to a better understanding of this pathogen, but the understanding of interactions between this pathogen and citrus is still lacking. Considering the importance of the disease to the citriculture and the current possibilities of molecular approach in plant-fungus interaction, this work proposes to study the transcriptome of sweet orange (susceptible MPC) and P. citricicarpa. The main goal is to investigate the host and pathogen responses at the same time, on the same sample, at the time of interaction through technical Dual RNA-seq. Furthermore, this work proposes the identification and characterization of effectors of this pathogen. Effectors are proteins that can deceive the defense responses of plants thereby resulting in disease.Understanding the changes in gene expression of both organisms simultaneously is a new and very interesting approach, since it is possible to evaluate changes at the same time the pathogen attacks and the plant tries to defend themselves. Additionally, this work will allow us to identify and characterize effectors that are probably used by the fungus to cause disease. (AU)