Abstract

VENTURA-MEDINA, Pedro Iván et al. Identification and cloning of three endogenous genes that may confer resistance to pathogens in citrus including CLas and CTV. Rev. mex. fitopatol [online]. 2019, vol.37, n.3, pp.399-420.  Epub Sep 30, 2020. ISSN 2007-8080.  https://doi.org/10.18781/r.mex.fit.1906-6.

Candidatus Liberibacter asiaticus (CLas), causal agent of Huanglongbing disease (HLB), and the Citrus tristeza virus (CTV)constitute a serious threat to Mexican citriculture because its endemic status in limes in several regions of the Pacific coast and also for the recent detection of severe strains, respectively. The identification and cloning of some genes related to the Systemic Acquired Resistance (SAR) of the plant could help to confront the diseases as an integrated management strategy. This work had the objective of cloning specific genes inherent to the plant as a first step to obtain transgenic citrus plants putatively resistant to CLas. The genes were selected based on the response of citrus plants to a wide range of pathogens, they were; a regulating gene for salicylic acid signaling (SA) as the inducer gen Azelaic Acid Induced 1 (AZI-1), a Citrus Non-Race-Specific Disease Resistance 1 (CsNDR-1) and a pathogenesis related protein 1 gen (PR-1). These three genes (AZI-1, PR-1 and CsNDR-1) were independently inserted into pUC118-FMV-Poly-2-1, subsequently they were subcloned individually into the vector pCAMBIA 2301 while gene AZI-1 was only cloned into pCAMBIA 2201. The CsNDR-1 construct was cloned into Agrobacterium tumefaciens strains EHA5 and AgL1 while genes AZI-1 and PR-1 could not be inserted into these strains of Agrobacterium. These constructions are the first step to be able to generate transgenic citrus as an alternative to face the HLB.

Keywords : SAR; plasmids; AZI-1; PR-1 and CsNDR-1.