UNEXPECTED DNA CONTENT IN THE ENDOSPERM OF CUPRESSUS-DUPREZIANA A-CAMUS SEEDS AND ITS IMPLICATIONS IN THE REPRODUCTIVE PROCESS

Nuclear DNA content of embryo and endosperm from mature and immature C upressus dupreziana A. Camus seeds was estimated using laser flow cyto metry. Relative DNA content of endosperm nuclei corresponded to four p loidy levels: 2C, 4C, 6C and 8C. The embryo nuclei invariably exhibite d a diploid pattern. In all endosperm tissue analyzed no haploid nucle us was found. This is problematic since, in gymnosperms, endosperm and female gametes originate from one functional haploid megaspore produc ed by meiosis. The possible origin and derivation of C. dupreziana end osperm are discussed in light of previous results concerning the two o ther Mediterranean cypresses, C. sempervirens and C. atlantica.