Response of Tobacco Root -Tip Cells to Various Sucker Control Chemicals

Effects of sucker control chemicals on cell division and differentiation were studied by observing changes in root-tip cells continuously submerged in 5 × 10^-3M solutions of MH-30 (maleic hydrazide), fatty ester T-43 (methyl caprate), fatty alcohol T-148 (mixture of 1-octanol and 1-decanol), Penar (dimethyldodecylamine acetate), and surfactants Tween-20 (polyoxyethylene sorbitan monolaurate) and Tween-80 (polyoxyethylene sorbitan monooleate). No adverse cytological effects were induced by surfactants. Meristematic cells treated with MH-30 appeared to be normal but there was no cell division. MH-30 also caused fragmentation or duplication of nuclei on differentiating cells. The effects of fatty materials (T-43 and T-148) include immediate swelling of the nucleus and then a general cessation of cell division. Penar caused enlargement of differentiating cells and nuclear fragmentation or duplication, a higher frequency of binucleate cells was found to be induced by Penar than T-148 or even MH-30. In general, sucker control compounds tested in this study induced a rather low incidence of endomitotic action which was limited to certain differentiating cells.