Metabolomic analysis of Citrus sinensis roots in the comprehension of Huanglongbing mechanism of infection

Abstract

Huanglongbing (HLB) is an incurable disease that affects citrus, causing economic losses in orchards around the world. The disease is caused by three species of bacteria limited to the phloem, but the most common is Candidatus Liberibacter asiaticus (CLas), whose vector is the psyllid Diaphorina citri. Once infected, the plant can take months to show symptoms, presenting an asymptomatic latency phase, in which it can be source of contamination of other surrounding trees. Thus, the detection of the disease is difficult and, when it occurs, the biological solution is to remove specimens from the orchard, reducing citrus production. The mechanisms of CLas infection are not fully understood, since its in vitro cultivation has not yet been successful in the laboratory. Therefore, the search for less aggressive ways to control the disease is based on studies of host-pathogen interaction. Studies have shown metabolic differences between different parts of the plant affected by HLB and healthy plants. The roots are one of the main regions of development and multiplication of CLas during the asymptomatic period, however, there are no extensive studies dedicated to this region of thehost and its role in disease development. Therefore, this project has the objective of carrying out the metabolomic study of roots of plants infected with HLB in order to study the host-pathogen interaction as a mean for the development of less aggressive treatments of the disease.