Cytoembryological studies on eastern galega (Galega orientalis Lam.) - a new papilionaceous plant

摘要

Embryogenesis, microsporogenesis and pollen development in eastern galega (Galega orientalis Lam.) have been analysed. Generally, the embryogenesis in eastern galega is similar to that of goat's rue (Galega officinalis L.). It is typical for easterngalega to form linear proembryos to the phase of 8 or 9 cells. The proper embryo develops from apical cells of the proembryo, while the remaining cells form the suspensor. The embryo of eastern galega typically forms a long, massive suspensor consistingof several irregular rows of cells on the side of the proper embryo and one large cell on the side of the micropyle. Suspensors were preserved in developing seeds possessing embryos with elongated cotyledons and a massive hypocotyl. In the initial phaseof embryogenesis the endosperm is of a nuclear type. The transformation of the nuclear into cellular type of endosperm begins at the heartlike embryo phase and proceeds from the micropylar to chalazal end. Observations on the embryogenesis in eastern galega revealed the presence of degenerating ovules. Causes of degeneration were not analysed. Meiotic division in PMCs leads to the formation of microspore tetrads via simultaneous cytokinesis. Mature pollen grains are two-celled with well-formed sporoderm and three germ pores through which pollen tube can emerge.