TAL Effector Repertoires of Strains of pv. in Commercial Cassava Crops Reveal High Diversity at the Country Scale.

Transcription activator-like effectors (TALEs) play a significant role for pathogenesis in several xanthomonad pathosystems. pv. (), the causal agent of Cassava Bacterial Blight (CBB), uses TALEs to manipulate host metabolism. Information about TALEs and their target genes in cassava is scarce, but has been growing in the last few years. We aimed to characterize the TALE diversity in Colombian strains of and to screen for TALE-targeted gene candidates. We selected eighteen strains based on neutral genetic diversity at a country scale to depict the TALE diversity among isolates from cassava productive regions. RFLP analysis showed that strains carry TALomes with a bimodal size distribution, and affinity-based clustering of the sequenced TALEs condensed this variability mainly into five clusters. We report on the identification of 13 novel variants of TALEs in , as well as a functional variant with 22 repeats that activates the susceptibility gene , a previously reported target of TAL20. Transcriptomics and EBE prediction analyses resulted in the selection of several TALE-targeted candidate genes and two potential cases of functional convergence. This study provides new bases for assessing novel potential TALE targets in the cassava interaction, which could be important factors that define the fate of the infection.