Revista mexicana de ciencias agrícolas
Print version ISSN 2007-0934
LOPEZ-GOMEZ, Pablo et al. Variation in tolerance to disinfectants of elite genotypes of Coffea spp. cultivated in vitro. Rev. Mex. Cienc. Agríc [online]. 2011, vol.2, n.5, pp. 645-657. ISSN 2007-0934.
The somatic embryogenesis can be affected by explants' oxidation when a common method of disinfection is. In the Experimental Field Rosario Izapa in 2006, the tolerance to disinfectants of leaf explants of coffee genotypes was determined by the median lethal dose (LD50) and based on its tolerance the optimal disinfectant for aseptic establishment was defined. The LD50 of sodium hypochlorite (NaClO), calcium hypochlorite (Ca[ClO]2) and the combination of both in leaf explants of Coffea canephora P. genotypes (INIFAP 95-8, 95-9, 97-10, 97-12, 97-15, 97-18, 97-19, 97-20, 00-24 and 00-28) and genotypes of C. arabica L. (INIFAP 2000-1018, 2000-1128 and 2000-692), was determined by applying eight concentrations of NaClO (0.1, 0.5, 1, 1.5, 2, 2.5, 3, 3.5%), eight concentrations of Ca(ClO )2 (3, 4, 5, 6, 7, 8, 9 and 10%) and the combination. Based on the tolerance, disinfection treatments were applied: 1, 3 and 6% of NaClO, 3.5, 7 and 10.5% of Ca (ClO)2 and control's combination of 3 and 7% NaClO and Ca(ClO)2, respectively. There was variability in the tolerance, since LD50 varied depending on genotype and disinfecting agent. Most genotypes were less tolerant to NaClO (LD50 from 2 to 4%); however, NaClO controlled pollution and oxidation at low doses (1 and 3%). NaCl and Ca(ClO)2 at low concentrations up to 2 and 3.5% respectively, these are an option for coffee explants disinfection that can ensure proper physiological state to initiate the embryogenesis.
Keywords : Coffea arabica L.; Coffea canephora P.; embryogenesis.