A comparative analysis of embryo-sac development in three closely-related Gagea Salisb. species (Liliaceae), with some consideration on their reproductive strategies

The embryo-sac development in Gagea bohemica, G. chrysantha and G. granatellii conforms to the “Euphorbia dulcis” type (= “Fritillaria” type), and all the three species are proterandrous. G. bohemica and G. chrysantha are embryologically closer to each other than to G. granatellii. G. bohemica and G. chrysantha develop both 7- and 8-nucleate female gametophytes, even if with clearly different proportions. G. granatellii shows instead only 7-nucleate embryo-sacs. All the species share, in various ways, cytological and micromorphological aberrations in both male and female gametophytes. Pollen grains are mostly morphologically regular in G. bohemica and G. chrysantha, while in G. granatellii malformed pollen is dominant. Lastly, the studied plants of G. bohemica and G. chrysantha produce a very low amount of seeds, while G. granatellii produces no seed at all