Associated with responses to biotic and abiotic stresses, the accumulation of callose is an important defense mechanism of the plants. Callose is a polymer of B-1,3-glucan units that accumulate on phloem sieve tube plates, on the wall of the pollen grains, pollen tube, on other cell wall reinforcing structures. In citrus, callose seems to play an important role in defense responses to biotic stresses. The question that arises is what is its role in the different citrus patosystems, especially in phloem-limited pathogens? The goals of the proposal are to perform studies on the expression of phloem genes in sweet orange during the infection of Candidatus Liberibacter spp, and, based in such results, to produce genetically modified sweet orange silencing genes involved in this response using the technology of RNAi. Such responses are usually known as effectors induced susceptibility.It is intended to intensify studies in biotechnology, with an emphasis on functional genomics, as tools to support the genetic breeding to obtain new cultivars. The results should contribute to obtain citrus plants with greater tolerance to HLB (huanglongbing) through gene silencing technology by RNAi. This contribution is consistent with the need to develop new citrus cultivars, particularly for HLB tolerance without being completely transgenic since RNAi technology is considered to produce non-GM plants. The proposal will support new lines of action of the institution in the area of citrus breeding for fruit quality for both the juice industry and the fresh fruit market.
News published in Agência FAPESP Newsletter about the scholarship: