Research Articles
Detection of sequence characterized amplified region (SCAR) markers linked to sex expression in Carica papaya L.
Authors:
E Niroshini ,
Institute of Biochemistry, Molecular Biology and Biotechnology, University of Colombo, Colombo 03, LK
JMDT Everard,
Coconut Research Institute, Bandirippuwa Estate, Lunuwila, LK
EH Karunanayake,
Institute of Biochemistry, Molecular Biology and Biotechnology, University of Colombo, Colombo 03, LK
TLS Tirimanne
Department of Plant Science, Faculty of Science, University of Colombo, Colombo 03, LK
Abstract
Carica papaya L. exhibits monoecious and dioecious plants that usually take six months for phenotypic manifestation. Nursery culling aided by sex-specific DNA markers was envisaged to alleviate the unnecessary cost incurred by farmers for maintaining unproductive male plants that contribute to 40-50% of the population. The mechanism of sex determination in papaya has been described as a tri-allelic single gene system with alleles, M1-dominant for maleness, M2-dominant for hermaphrodism and m-recessive for femaleness with diploid zygotes; M1M1, M2M2 and M1M2 being inviable. Bulked DNA samples of male, female and hermaphrodite plants were amplified by Random Amplified Polymorphic DNA-Polymerase Chain Reaction (RAPD-PCR) using 100 random primers. Twenty of most promising of these were analyzed among individual sex types. Two sex-specific fragments, OPC09-1.7 and OPE03-0.4 were associated with maleness and hermaphrodism. The segregation of these two markers was analyzed in the F1 population obtained by self-pollinating a hermaphrodite plant. A linkage was detected between the RAPD markers, OPC09-1.7 and OPE03-0.4 and the male and hermaphrodite sex of papaya plants. These sex-specific RAPD fragments were cloned and sequenced for converting them to more authentic SCAR markers. The Southern blot hybridization of RAPD-PCR products obtained by amplification of female, male and hermaphrodite papaya DNA amplified by OPC09 primer using radio labeled recombinant plasmid detected a polymorphic fragment in male and hermaphrodite papaya sex types. The nucleotide sequence of OPC09-1.7 fragment showed the possibility of developing more authentic SCAR markers to enhance the accurate sex determination of Carica papaya at the nursery stage.
Keywords: Carica papaya, papaya, SCAR marker, sex linked polymorphism
doi:10.4038/jnsfsr.v36i2.146
Journal of the National Science Foundation of Sri Lanka 36 (2) 145-150
How to Cite:
Niroshini, E., Everard, J., Karunanayake, E. and Tirimanne, T., 2008. Detection of sequence characterized amplified region (SCAR) markers linked to sex expression in Carica papaya L.. Journal of the National Science Foundation of Sri Lanka, 36(2), pp.145–150. DOI: http://doi.org/10.4038/jnsfsr.v36i2.146
Published on
25 Jun 2008.
Peer Reviewed
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