Lack of mother tree alleles in zymograms of Cupressus dupreziana A-Camus embryos

Unexpected ploidy levels observed in a previous flow cytometric analysis of Cupressus dupreziana endosperm, led us to hypothesize an asexual seed prod uction in this endangered species. We tested here this possible apomixis, s tudying isozyme variability of endosperms, embryos and seed coats extracted from open pollinated seeds. Electrophoretic bands observed in zymograms of PGI2 and LAP, the only two polymorphic systems, were in agreement with ban ds observed in C. sempervirens zymograms. Zymograms of C. dupreziana endosp erms were identical to those of the diploid maternal tissue, as observed in C. sempervirens. Hypothesizing a codominant nuclear DNA control for both P GI2 and LAP, a similar electrophoretic expression of these systems in endos perm and embryo, and the absence of modifier genes, the lack of endosperm b ands in most embryo zymograms was interpreted as the result of a strictly p aternal origin of embryo nuclear DNA in C. dupreziana seeds.