| Abstract: | The effects of different growth regulators on the sproutingof hydrilla reproductive propagules (Hydrilla verticillata (L.F.)Rovle) were studied. Some growth regulators either had no effector inhibited sprouting. Ethephon, gibberellic acid, and thioureaincreased tuber sprouting significantly. Thiourea was less effectivein inducing sprouting in turions than in tubers. Maintainingtubers at 5 ± 2°C enhanced sprouting significantly.Tubers harvested in summer responded differently to growth regulatorsthan some of the tubers harvested in winter. Therefore, it wasconcluded that two types of dormancy exist in hydrilla tubers. |
