Production and maintenance of large numbers of Dugesia tigrina (Turbellaria: Tricladida) for the control of mosquitoes in the field.

Methods to increase and preserve Dugesia tigrina for mosquito control purposes through cocoon production, mechanical sectioning and cold storage were examined. Cocoon production was an ineffective and unreliable means of increasing planarian numbers, with an average of only 0.19 cocoons containing 0.74 young produced per adult per week. In comparison, mechanical sectioning proved to be more appropriate for increasing the number of planaria. One hundred planaria averaging 8 mm in length could be sectioned into 600 segments in approximately 18 min; regeneration was achieved by approximately 94% of these segments, usually within 8 days after sectioning. Techniques were developed to store planaria at 10 degrees C until needed for field release.