There have been no studies of significance that have been conducted to seek biocontrol agents for hygrophila to date. Element 3, Task 2, Foreign exploration for natural enemies of hygrophila, coordinated by Dr. James Cuda, has initiated foreign exploration of natural enemies of hygrophila in India. Dr. Cuda has established collaboration with scientists and institutes in the native range of hygrophila and is searching for natural enemies of hygrophila to culture and evaluate for potential introduction into quarantine in Florida.

Populations of hygrophila in India have been located by consultation with taxonomists and reviewing herbaria records and natural populations of hygrophila have been sampled for insect herbivores. Insects are in the process of being identified to the furthest extent possible and cultured on hygrophila to increase populations and then placed back on insect free hygrophila to determine the extent of herbivory. Following preliminary testing for host specificity in India, insects will be considered for seeking USDA approval for introducing into quarantine in the US.

Element 3, Task 3, Collaborative Effort to Search for Natural Enemies of Hydrilla in East Africa is coordinated by Dr. Bill Overholt. The search for natural enemies (insects primarily) of the invasive submersed weed hydrilla has been concentrated in Southeast Asia and Australia over the past 30 years. Several potential insect biocontrol agents have been introduced, but these have not had significant impact on hydrilla growth.

Some of the activities for this component include:

• Literature, herbaria and new field survey data will be used to develop a geo-referenced database of hydrilla occurrence in East Africa.
• Hydrilla specimens will be analyzed for molecular structure and compared to Florida hydrilla molecular structure in order to ascertain whether the hydrilla is similar enough in structure for biocontrol viability.
• Insects will be collected and evaluated for herbivory on hydrilla.
• Arthropods, which appear to be specific to hydrilla and cause measurable damage to plants, will be imported into quarantine in Florida for host range studies following approval of federal and state authorities.

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