Research continued for a fourth year on the organic hormone methyl farnesoate for potential control of tadpole shrimp. While searching for food, this invertebrate pest uproots young rice seedlings and reduces yield. An alternative to copper sulfate (bluestone) is necessary, as increasing field copper levels may spur new regulation. 

The compound has been successfully incorporated into a pellet containing a standard crustacean feed mixture of casein, lecithin, wheat gluten and albumin. To protect the compound from oxidation, methyl farnesoate was encapsulated into microscopic structures known as liposomes. The liposomes then are incorporated into pellets.  These pellets have proven effective at interfering with tadpole shrimp reproduction.

Laboratory studies are more closely examining the nature of inhibitory effects by the new pellets. Radioactive tracers showed the highest activity of synthetic capacity was in the head or cephalic region, as well as ovaries and other reproductive organs.

Research to determine the effective dose range and impact to tadpole shrimp reproduction has been delayed by lack of soil with significant tadpole shrimp cysts. New testing is planned for the 2007 season.