DISORGANIZATION OF DICTYOSOMES BY MONENSIN TREATMENT OF IN-VITRO GERMINATED POLLEN OF MALUS-DOMESTICA BORKH

Ultrastructural alterations of dictyosomes after treatment with monova lent ionophore, monensin, were studied in pollen tubes of Malus domest ica Borkh. The cisternae of dictyosomes in pollen tubes, grown in the presence of 125 nm monensin for 60 min, appear dilated and the interva l between two consecutives is enlarged. These changes are stronger tow ards the pollen tube apex. The number of large vesicles is decreased. In pollen tubes treated with 125 nM monensin for 120 min cisternae are swollen. Unlike the small vesicles, the large ones become hardly reco gnizable and do not react or react weakly to the polysaccharide test.