SciELO - Scientific Electronic Library Online

vol.25 issue2SYSTEMATIC CONSIDERATIONS ON TWO SPECIES OF NECTARIVOROUS BATS (Anoura caudifer AND A. geoffroyi) BASED ON BARCODING SEQUENCES author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand




Related links

  • On index processCited by Google
  • Have no similar articlesSimilars in SciELO
  • On index processSimilars in Google


Acta Biológica Colombiana

Print version ISSN 0120-548X


BARRERA, Andrea del Pilar; SOTO-SEDANO, Johana  and  LOPEZ CARRASCAL, Camilo Ernesto. Identification of polymorphisms in the Cassava RXAM1 Gene and the association with Cassava Bacterial Blight Resistance. Acta biol.Colomb. [online]. 2020, vol.25, n.2, pp.185-193. ISSN 0120-548X.

Cassava (Manihot esculenta Crantz) is an essential crop in tropical regions providing food for about one billion people around the world. The most important bacterial disease is cassava bacterial blight (CBB) caused by Xanthomonas axonopodis pv. manihotis (Xam). Recently, a resistance gene called RRXAM1 was identified, which codes for a protein that has an extracellular LRR (Leucine-Rich Repeat) domain and a cytoplasmic STK (Serine Threonine Kinase) domain. RXAM1 colocalizes with a QTL explaining 13 % of the resistance to the CIO136 strain of Xam. In this work, the response to infection with the strain XamCIO136 in ten different varieties of cassava was evaluated, which allowed the classification of the cassava varieties TMS60444, SG10735, MCOL1522, MCOL1505 and MCOL2215 as susceptible, while CM6438-14, CM523-7, and MBRA902 were cataloged as resistant. Also, SNPs (Single Nucleotide Polymorphism) polymorphisms were identified in the RRXAM1 gene in the same group of cassava varieties. SG10735, CM6438-14, TMS6044, and MBRA685 presented the highest level of polymorphisms, while the varieties CM523-7, CM2177-2 and MCOL1522 were less polymorphic for this gene. The statistical analyses did not allow to identify a significant association between the phenotype and the identified polymorphisms. This study represents a first effort towards the establishment of associating between allelic variants and the cassava response to bacterial blight.

Keywords : Allele; diversity; receptor; symptoms in plants.

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )