FABI congratulates Robert Backer who marked the milestone of completing his PhD study with a prestige seminar on 6 February. His presentation summarised his thesis, “Molecular and bioinformatic analysis of the Persea americana (Mill.) NPR1-dependent defence signalling pathway in response to Phytophthora cinnamomi infection”. Robert completed this this study under the supervision of Professor Noelani van den Berg and Prof. Sanushka Naidoo. 

Robert investigated the role of the NPR1 defence response pathway in Persea americana during Phytophthora cinnamomi infection. P. cinnamomi is the causal agent of Phytophthora root rot, a threat to avocado production worldwide. The pathogen reduces the plant’s ability to take in water and nutrients, which can lead to its death. Robert identified five NPR1-like genes in P. americana, three of which had strong support for their role in defence responses. He also identified 116 NPR1 pathway-associated genes. He conducted expression analyses on the 116 identified NPR1 pathway-associated genes over time, and between P. cinnamomi susceptible and partially resistant rootstocks. 

This study investigated the mechanisms used by P. americana to establish systemic acquired resistance and determined crucial differences between susceptible and partially resistant P. americana-P. cinnamomi interactions. Prof. van den Berg congratulated Robert on what she described a “brilliant” study.