• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.1 no.1
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• pp.61-67
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• 1997

The effects of Insect growth regulator Dimilin which interfere with the synthesis of chitin in the cuticle of insect larvae were investigated at various concentrations using the copepod larvae of Tigriopus japonicus Mori. The larvae were cultured at control, 1, 5, 10, 20, 50, and 100 ppb Dimilin solutions and three replicate experiment were carried out to give correct analysis. Lethal effects of Dimilin on larvae of T. japonicus occurred above 1 ppb Dimilin solution after 8 days. $LC_{50}$ of larvae was 50 ppb Dimilin on the 4th day. Lethal effects of Dimilin on adults or T. japonicus occurred above 20 ppb Dimilin solution after 13 days. $LC_{50}$ of adults was 50 ppb Dimilin on the 12 days. Egg viability has little relation to Dimilin solution concentrations.

• Journal of Environmental Science International
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• v.1 no.1
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• pp.61-67
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• 1992

The effects of insect growth regulator Dimilin which interfere with the synthesis of chitin in the cuticle of insect larvae were investigated at various concentrations using the copepod larvae of Tigriopus japoniu Mori. The larvae were cultured at control, 1, 5, 10, 활, 50, and 100 pub Dimilin solutions and three replicate experiment were carried out to give correct analysis. Lethal effects of Dimilin on larvae of T japoniu occurred above 1 ppb Dimilin solution after 8 days. LC50 of larvae was 50 ppb Dimilin on the 4th day. Lethal effects of Dimilin on adults of T. japoniu occurred above 1 ppb Dimilin solution after 13 days. LC50 of adults was 50 ppb Dimilin on the 12 days. Egg viability has little relation to Dimilin solution concentrations.

• The Korean Journal of Ecology
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• v.13 no.1
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• pp.19-24
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• 1990

The effects of insect growth regulator Dimilin which interfere with the synthesis of chitin in the cuticle of insect larvae were investigated at various concentrations using the crab larvae of Hemigrapsus sanguineus. The larvae were cultured at control, 0.5, 1, 5 and 10 $\mu g$ Dimilin solutions and three replicate experiments were carried out to give correct analysis. Significant differences in percent mortality have occurred between control and 10$\mu g$ when the larvae were exposed to Dimilin whereas no differences were found between 5 and 10$\mu g$ Dimilin concentrations. If lethal concentration is defined as concentration at which less than 10 percent of crab larvae reach to the last zoeal stage from hatching it can be concluded that insect growth regulator Dimilin is lethal to the larvae of Hemigrapsus sanguineus at 5 and 10$\mu g$ Dimilin.

• The Korean Journal of Ecology
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• v.21 no.6
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• pp.799-804
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• 1998

laboratory experiments were conducted to determine the effects of Dimilin, an insect growth regulator which acts to inhibit chitin synthesis, during the larval development of liocarcinus corrugatus Pennant. The larvae was exposed to control (10 ppb acetone sea water and untreated sea water solution) and five concentrations 0.1, 1.0, 5.0, 10.0 and 25.0 ppb of both TG and WP-25 formulations of Dimilin from the hatching to the megalopal stage, and the effect of Dimilin on development of the larvae were determined. Two formulations (TG and WP-25) had different effect on the different stages in L. corrugatus. and early stage larvae of L. corrugatus were more sensitive to TG than to WP-25. Concentrations of diflubenzuron >5.0 ppb are lethal to L. corrugatus larvae upon chronic exposure. Lethal concentrations are defined here as those in which less than 10% of the larvae survived to the megalopal stage. However, Dimilin (TG and WP-25) showed no significant effects on developmental time of L. corrugatus larvae.

• The Korean Journal of Ecology
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• v.15 no.3
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• pp.257-265
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• 1992

The effects of insecticide dimilin including the technical grade(tg) and wettable power(wp-25), inhibiting the synthesis of chitin in the cuticle of insect larvae, and herbicides alachlor and atrazine on the development of shrimp caridina denticulata denticulata were investigated in various concentrations. This species is abundant in the freshwater such as river and pond. The shrimp larvae were reared at dimilin solutions(tg and wp 2), alachlor solutions, and atrazin solutions. the concentrations of dimiline were 0, 1, 5, 10 and 25 ppb dimilin solutions, and those of alachlor and atrazin were 0, 1, 5, 10 and 25ppm, respectively.mortality was high at 10 ppb when the larvae were exposed to dimilin and at 25ppm in the case of alachlor and atranzine solutions. If lethal concentration is defined as a concentration in which less than 10% of larvae to the post larval stage from hatching it can be concluded that the lethal concentration of dimilin is 5ppb, and that of alachlor and atrazin is 25 ppm.

• Korean Journal of Environmental Agriculture
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• v.4 no.2
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• pp.108-113
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• 1985

Aerial application tests with a biological insecticide (Thuricide$^{(R)}$) and two low toxicity insecticides, Diflubenzuron (Dimilin$^{(R)}$) and Triflumuron (Alsystin$^{(R)}$) were carried out against the fall webworm (Hyphantria cunea Drury). For experimental application by helicopter, dilutions of 30x and 45x Thuricide, 180x and 240x Alsystin, and 180x Dimilin were utilized. The solutions were applied at a rate of 30 liters per hectare. The results are as follows: 1) All treatments, Dimilin 25% wp, Thuricide wp, and Alsystin 25% wp, were found to very effec tive against fall webworm larvae. Percentages of mortality averaged between 93.9% and 97%. 2) No significant differences in percentages of larval kill were found between dilutions of Thuricide (30x and 45x) or Alsystin (180x and 240x). 3) Assessment of parasite densities in the treated areas 35 days after treatment indicated that percentages of reduction for all five species found, including Brachymeria lasus(Walker) (=obscurata [Walker]), were lower than for areas treated with the conventional insecticide Diplox$^{(R)}$ (trichlorfon) 25% wp. In particular, the percentage of reduction in Thuricide-treated areas was only 21% as compared with the untreated (control) areas. 4) Aerial applications of Dimilin were very effective and economical for control of the fall webworm by comparison with [aerial] applications of Thuricide.