Factors influencing the abundance and distrubution of the house dust mites, Dermatophagoides farinae and D. pteronyssinus are discussed. Comparing the duration of development, the number of oviposition, and the longevity of adults among Pyroglyphidae, Acaridae, Glycyphagidae and Cheyletidae, it is revealed that Pyroglyphidae mites have characteristics of slower growth rate, fewer oviposition, and longer adult duration than other mites. These characteristics are considered to be a reflection of those of house dust ecosystem. Although both mite species occupy similar ecological niche and are prevailing in almost equal proportion in homes in central Japan, there are some differences in their distribution and population dynamics. D. farinae predominated over D. pteronyssinus in wooden houses with high room ratios (family size/number of rooms), and in high-floor homes of concretebuilt apartments. Moreover, D. farinae exhibited more distinct seasonal fluctuation of population densities and structures than D. pteronyssinus did. These differences between the mites are attributed to the difference in their life histories and humidity requirements. The life history of both mites includes egg, protonymph, tritonymph, and adult, and requires about one month to develop from egg to adult under optimun conditions. D. farinae has an additional stage, prolonged quiescent protonymph which occurrs in an overcrowded condition and has the ecological significance of diapause. The humidity requirements of D. farinae are distinctly lower than those of D. pteronyssinus. Thus it is concluded that D. farinae adapt to a relatively dry environment and D. pteronyssinus to a rather humid environment.

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Susceptibility of larva and adult of a scuttle fly, Megaselia scalaris (Diptera: Phoridae), to 12 insecticdes including 3 insect growth regulators (IGRs), 6 organophosphates, 1 carbamate and 2 pyrethroids was investigated in the laboratory.
A medium incorporating method was adopted to determine the effect of the insecticides against the larva. Although the most effective insecticide was chlorpyrifos-methyl among 9 compounds, all the tested compounds required high concentrations to kill the insects. This shows difficulty with the chemical control against the larva.
Against the adult, the knockdown effect of 7 compounds was evaluated by a continuous contact method on the filter paper at a dosage of 250mg/m². In this test, the highest knockdown effect was obtained with chlorpyrifos-methyl, followed by dichlorvos, permethrin, diazinon, dl, d-T80-allethrin, prothiofos and propoxur.
These results indicated that the susceptibility of this scuttle fly was lower than that of susceptible strains of the house fly.

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A family of four members who kept a cat and a dog in the room, had been suffered from heavy itch for 10 months. Fourty three mites, Cheyletiella blackei, were detected in the house dust from the room floor and bed clothes. Also 57 mites of the same species were found in the cat's carpets. The itching disappeared when the pet animals were treated with acaricide.

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A survey of infestation of Indian meal moth by sex pheromone trap baited with (Z,E)-9,12-tetradecadienyl-acetate was conducted at 120 house environments of 28 cities in Japan. One trap was set on refrigerator in kitchen, and another on 2-5 meters apart from house, suchas garage, warehouse or patio, for seven days in summer of 1994. Total 8,202 phycitinae moths (inside; 3,593, outside; 4,609) were trapped. The 95.1% of trapped moths was Indian meal moth, 4.1% was Almond moth and 0.8% was Mediterranean flour moth. Of 120 house, 105 house (87.5%) were infestated by Phycitine moth, mainly Indian meal moth, and outside environments of 113 house were infestated too. Average numbers of Phycitinae moth per trap were 29.9±33.0 (S. E) in house, and 38.4±38.2 (S. E) outside of house. Indian meal moth is very popular "Household insect" in Japan. Food infestations by it might be often occurred during storage in house.

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Responses to traps were compared among stored product insects in two rice mills and a feed factory. To verify of inhabitation of stored product insects in plant, vaccumings of floor dust were conducted at many points. Sticky sheet traps, fly ribbon traps, light traps and sex pheromone traps (Phycitinae moth traps and cigarette beetle traps) were set for seven days in June 1994. The sticky sheet trap can collect wide species of insects, but a small number. The fly ribbon trap can collect flying insects such as indian meal moth, cigarette beetle and red-flour beetle. The light trap can collect phototaxis insects such as cigarette beetle, red-flour beetle, varied carpet beetle and black carpet beetle. Indian meal moth and cigarette beetle can be more effectively detected by the phromone traps than other traps.

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When confined individually in plastic containers (3cm diameter and 5cm depth) with no carton shelters, diapause fully-grown larvae wandered for 36-48 hours at 25-26℃ before stopping and making cocoons. They crept at an average speed of 10cm/39.1±SD12.5(male)-33.0±SD6.7(female) seconds on a paper sheet at 19-20℃. This suggests that they could move more than 221m within the first 24 hours. Non-diapause fully-grown larvae wandered for 12-24 hours at 27℃, and their speed was 10cm/25.2±SD6.4(male)-22.6±
SD3.8(female) seconds, also suggesting their movement of more than 171m for the first 12 hours. Provided with a piece of carton (1cm×1cm) as a shelter in each container, both the types of fully-grown larvae quickly entered the carton shelters (within 3-24 hours), without wandering so long. Extended lighting in every evening induced diapause larvae to pupate quickly when they had no shelters, while the diapause was hardly broken when the larvae could get into the shelters as well as in the case where the containers were kept in darkness. Both the types of fully-grown larvae tended to climb upwards, but showed stronger negative phototaxis.

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[in Japanese]

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The distribution of adult red flour beetles, Tribolium castaneum H., was observed in and around the food (plain flour+10% dried yeast powder) in each container the bottom of which was covered with a piece of cotton gauze or a sheet of cardboard. Most of the adults did not enter the food because they could'nt climb the smooth wall of the food case. Most of the adults, however, entered the food as soon as the wall was covered with a piece of tissue paper. This suggests that the starved adults did not fly to food at least for 5 days during the experiment. After they ate the food, a substantial number of the adults were out of the food, and got together at the confined places, especially between the gauze and the bottom of the container.

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The 12 hours interval spray of the mixture of fenothrin and CO₂ gas to a next room of the vehicle entrance at 7:00 a.m. and p.m. was effective to prevent flying insects from invading to a printing factory.
The numbers of the flying insects captured by the light trap in indoor have been decreasing since treament of mixture gas. And the numbers of insects captured by the light trap with adhesive in next room of the treatment room on mixture gas was decreased one-tenth after treatment.

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We prepared a candidate bait formulation, K5-123, containing microencapsulated fenitrothion, already registered in Japan, as an active ingredient. And we evaluated the insecticidal activity for German and smokey brown cockroaches in comparison with those of some cockroach bait products using various kinds of laboratory test method. In small container (W20cm×L35cm) test, K5-123 got to 100% mortality at one day for German cockroaches and at 5 days for Smokey brown cockroaches after treatment, but a boric acid product got to 100% mortality at 8 days and at 12 days respectively. And in large container (1m²) test for German cockroaches, K5-123 also got to 100% mortality at 2 days after 5g treatment. Transferring killing effect of K5-123 for German cockroaches was tried to evaluate by giving the dead bodies or the feces of the cockroaches after treatment with bait to untreated colony in comparison with those of a hydramethylnon (gel) product. The results showed K5-123 was superior to a hydramethylnon on transferring effect. From these results described above, it can be said this formulation is expected to be used in practice.

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Field trials of K5-123 for cockroach control were conducted twice at a restaurant in Osaka Prefecture, 1995-1996.
Nineteen sticky traps were set all over the restaurant (around 33m²) and population density of cockroaches was caliculated by ordinary procedure.
Initial density of the population in the place was more than 36 (individuals/sticky trap/day) and the cockroach species was German cockroach only.
First trial was made by using only K5-123 which was treated at 5.5g/m² like line and spot to near by their habitat as possible and to the corner area of the floor, furnitures, sinks, refrigerators and etc. Population density declined to below almost 5 after 14 days and gradually decreased down to 2 after 1 month. And then, it was going to recover after 77 days.
Second trial was conducted by using both K5-123 and fenitrothion 20% MC formulation as residual spray soon after the first trial. K5-123 was newly treated in the same way as the first trial treatment after the residue of K5-123 were removed. And 50 folds water dilution of fenitrothion 20% MC was sprayed to corners of the floor and up to 1.5m height of wall surface of the cooking room at the rate of 50ml/m². The density was decreased up to 0.2 after 1 month and kept such the low level for more than 9 months.
From these results, K5-123 is convinced to be useful inpractice for cockroach control. However, it was suggested there are some limits in single bait treatment for cockroach control, because the control area like a restaurant is of heavy complex structures and with abandant foods which are cockroach's favorite. And it was of great interest that when bait accompanied with residual spray was treated, its effect was much greater than those of single bait treatment.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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