Sperm cells of Plumbago zeylanica express structural dimorphism in which the sperm cell associated with the vegetative nucleus (Svn) usually fuses with the central cell. The sperm cell unassociated with the vegetative nucleus (Sua) fuses with the egg cell. In order to investigate potential differences in gene expression between these two cells, paired sperm cells were released from pollen in a 10 mM MOPS buffer containing 0.8 M mannitol (pH 4.6). Sperm cell types were identified in paired cells based on size differences and sperm cells were collected individually with a microinjector. Viability, tested using FCR, indicates that sperm cells isolated under these conditions remain viable for at least 2 h. Two PCR based cDNA libraries were constructed using mRNAs isolated from separated Sua and Svn sperm cell populations. Preliminary screening of libraries establishes the feasibility of the technique and suggests differences in gene expression profiles between the two sperm cell types.

Key words: cDNA library, male gametes, Plumbaginaceae, Plumbago zeylanica, sperm collection, sperm isolation