Int. J. Dev. Biol. 35: 335 - 340 (1991)
© UPV/EHU Press

Effect of insecticides (Dimiline WP 25, Torak EC 24 and Gamacide 20) on hydra (Hydra vulgaris Pallas).

M Kalafatic, D Znidaric, A Lui and M Wrischer

Institute of Zoology, Faculty of Natural Sciences and Mathematics, University of Zagreb, Republic of Croatia, Yugoslavia.

ABSTRACT Investigations showed that the three insecticides used had the most damaging effect upon hydra immediately after treatment. The tentacles and the hypostome are the parts most often damaged. Inse the affected cells, lesions appear in the intracellular membranes, the nucleus shell and the membranes of the mitochondria, Golgi complex and the endoplasmic reticulum, while the cell membrane is preserved. The damaged parts of the body regenerate within three days. Zymogen cells play a significant role in the course of regeneration. They dedifferentiate into gastrodermal interstitial cells and later into other types of cells of the ectoderm and the gastroderm. Apart from their intense participation in regeneration, these totipotent cells also invariably participate in the formation of new hydra buds. It was observed that Dimiline WP 25 and Torak EC 24 in the concentrations used stimulate asexual reproduction of this animal.