Abstract

Sex determination of Zamia fischeri Miq., one of the endangered cycads was done using peroxidase profiling, two-dimensional gel electrophoresis of proteins and RAPD-based approaches to find an easy and reliable molecular marker. Sex at pre-flowering stage could not be resolved by peroxidase isozymic profiling. Use of sex organ specific tissues as enzyme source resulted in marked differentiation in peroxidase profiles. Fifteen unique spots of relatively high molecular mass were noted in microspore derived protein (male) sample while twenty five unique spots ranging between 20 to 94 kD were identified in ovule derived protein (female) sample as resolved by two dimensional gel electrophoresis. DNA from leaf samples of contrasting sex resulted in four male and female specific RAPD derived DNA fragments (two each of both sexes) of which one male specific band showed homology with micro satellite sequence of Araucaria angustifolia; this can be used as a convenient molecular marker for sex determination of Zamia fischeri at pre-flowering stage.

Key words: Molecular marker, RAPD, Sex determination, Zamia fischeri.