Isolation and Characterization of Novel Microsatellite Markers in Chayote [Sechium edule (Jacq.) Sw.]

Chayote [Sechium edule (Jacq.) Sw.] is an economically important species in Latin America; however, there are very few reports available regarding its genetic diversity. Out of 11 microsatellite markers isolated, 10 loci provided 1 to 7 alleles per locus in a set of Mexican chayote accessions. Observed and expected heterozygosities for each locus ranged from 0.00 to 0.85 and 0.00 to 0.73, respectively. The overall genetic diversity detected by microsatellites was compared with that detected by P450-based analogue markers, a genome-wide dominant marker. Genetic diversity values obtained by the newly designed microsatellite markers were almost equal to the value estimated by PBA markers, but genetic distances calculated by both marker systems were not significantly correlated. Additional microsatellite markers, which could detect more polymorphisms, may be necessary to analyze the genetic diversity and structure of Mexican chayote collections.