Ns. Tietze et al., INTEGRATED MANAGEMENT OF WASTE TIRE MOSQUITOS UTILIZING MESOCYCLOPS-LONGISETUS (COPEPODA, CYCLOPIDAE), BACILLUS-THURINGIENSIS VAR ISRAELENSIS, BACILLUS-SPHAERICUS, AND METHOPRENE, Journal of the American Mosquito Control Association, 10(3), 1994, pp. 363-373
This study evaluated the compatibility and efficacy of using a predato
ry copepod, Mesocyclops longisetus in concert with 3 ''biorational'' c
ompounds for mosquito control in waste tires. The toxicity of Bacillus
thuringiensis var. israelensis (B.t.i.), Bacillus spharericus, and me
thoprene to Mesocyclops longisetus was assessed in the laboratory usin
g concentrations 10 times the maximum labeled or suggested rate and ba
sed on a water depth of 7.6 cm. Microbials were tested using mature co
pepods exposed for durations of 24, 48, and 72 h. Methoprene bioassays
consisted of individually exposing newly hatched copepods (i.e., naup
lius larvae) and monitoring their development to maturity. The toxicit
y tests indicated B.t.i., B. sphaericus, and methoprene were not delet
erious to copepods at concentrations exceeding those expected in the f
ield. Copepods exposed to methoprene matured normally, and when mated,
50% developed egg sacs. A 5-month field test, integrating the copepod
and B.t.i., B. sphaericus, and methoprene provided better mosquito re
duction together than either copepods or control agents alone. When co
pepods were combined with B.t.i. or methoprene, overall reduction of 3
rd- and 4th-instar larvae during the 5-month interval was equal to or
greater than 90%. Bacillus thuringiensis var. israelensis alone tempor
arily produced a high degree of larval reduction (up to 100%), however
reapplications were necessary to maintain that level of control. Of a
ll the treatments, B. sphaericus alone produced the lowest degree of m
osquito suppression due to lack of toxicity to Aedes albopictus, the p
redominant species during the study. It is recommended that mosquito c
ontrol managers consider integrating M. longisetus and B.t.i. or metho
prene against mosquitoes in waste tires.