Cytophotometric contribution to the knowledge of ceratonia siliqua seed development

Abstract

Cytophotometric analysis of nuclear DNA content in differen áreas of young Ceratonia siliqua seeds were made. The relative DNA amount in 50 interphase nuclei per each area were determined using a Vickers M 85 cytodensitometer. The frequency distribuition of DNA content in individual nuclei falls in the 2C and 4C classes, with the predominance of 2C nuclei. The DNA content of normal endosperm nuclei range from 2C to 6C (external layer) or from 2C to 9C internal layer), with the predominance in both cases of 3C class, thus agreeing with the triploid constitution of this tissue. Some cases of abnormal, collapsed-like embryos, accompanied by diploid (2C and 4C classes) endosperm, were detected. The possible involvement of diploid endosperm in failure of embryos development, as frequently observed in Ceratonia siliqua, is discussed.