Abstract: | Many studies have showed that apoptosis exists in plants. Our study shows that (1) menadione(VK3) induces apoptosis in suspension cultures of carrot cells; (2) heat shock induces apoptosis in suspension cultures of tobacco cells; and (3) ethrel induces apoptosis in carrot protoplasts. Some important indications of apoptosis were observed, including DNA laddering, TUNEL-positive reaction, condensation and degradation of nuclei.[ |