Evaluación de marcadores moleculares tipo SCAR para determinar sexo en plantas de papaya (Carica papaya L.)

In this study the molecular markers SCAR- SDSP, SCAR T1 and W11 -reported as sex discriminators at seedling level-, were used to validate the effectiveness in flowered plants in the field. SCAR-SDSP amplified a band of 369 bp in male and hermaphrodite plants which allows corroborate the results obtained with this marker, developed at Corpoica using Colombian genotypes, in a previous study. With the use of the SCAR T1 and W11 markers combined in one reaction, it was possible to differentiate female and hermaphrodite plants. When the sex prediction was done with a blind sample using two months-old plantlets, from commercial seeds, a ratio of 1:1 female:hermaphrodite was observed, according to the segregation pattern of a cross between these two types of plants. The amplification with the SCAR W11 generated a band of 800 bp in male and hermaphrodite plants, independently of the sample's place of origin. However, when this band was sequenced and analyzed with the BLAST program, the analysis showed 98% identity between male and hermaphrodite sequence.