Cytological effects of phenothiazine tranquilizing agents on barley meristems

A growth reduction of 30--40% was noted in barley plants grown in two phenothiazine tranquilizers. Similar reductions were noted in the number of mid-anaphase cells, indicating the reduced growth could have been the result of a reduced mitotic rate. Also observed were several types of chromosomal aberrations. Electron microscopy revealed less endoplasmic reticulum and cytoplasmic organelles in the treated cells than in untreated cells. Various sized discontinuities in the nuclear membrane was the most frequent abnormality observed in the electron micrographs. The abnormal nuclear membrane was possibly a result of enzyme degradation.