Physiological and Cytological Effects of BAS 9052 OH on Corn (Zea mays) Seedlings

Abstract

Four days after treatment of corn (Zea maysL. 'SX111′) seedlings with BAS 9052 OH {2 - [1-(ethoxyimino) butyl] - 5 - [2 - (ethylthio) - propyl] - 3 - hydroxy - 2 - cyclohexene-1 - one} growth was inhibited and a purple color developed in the leaves. Low dosages (0.02 and 0.04 kg/ha) caused bleaching of the newly expanding leaves. Dosages higher than 0.04 kg/ha caused significant reductions in length and fresh and dry weights of both shoots and roots. Anthocyanin and total - sugar content increased, whereas chlorophyll accumulation and respiratory activity were reduced by herbicide treatment. BAS 9052 OH did not alter the mitotic index of corn root tips, but induced binucleate cells by preventing cell-plate and -wall formation. In some cells, the daughter nuclei were reoriented with respect to the longitudinal axis of the cells, and in others, the nuclei failed to migrate to the poles. These physiological and cytological effects of BAS 9052 OH on corn seedlings may be responsible for the phytotoxic action of the herbicide on grasses.