1) Studies on the inhibitory effect on the oothecal formation in cockroaches revealed that UV radiation transmitted through the rubber-like cuticle of antacoria were accepted by photoreceptor cells with phaosome found in the nerve-cord-like structure under antacoria, and stimuli of the UV radiation recovered the secretory activity of the corpora allata in female at the early stage of the oothecal formation, as a necessary consequence, the secretion of the collererial glands were inhibited.

Also, it was confirmed that the inhibitory and delaying effects of UV radiation on the molting were occured by alternating of the secretory activity in the corpora arata in the nymphal stage.

In adult of the German cockroach, it was found that the directory letal effect was cumulated and photo-recovery phenomena were not detected.

These results did not suport a convetional hypothesis that the lethal effect in the insects was due to thymine dimers formed in DNA of the hypodermal cells by UV radiation.

2) Repelency of cockroaches to UV radiation was not supoted by auto-behavioral records for long time and foot traces on the smooky papers laid under the girmicidal lamps in the releasing test.

3) Two test of cockroach control with UV radiation, release experiment in the constant temperature room and field test in natural habitat of the German cockroach were performed. In release experiment, more than 70% of adults German cockroaches dead for 4 days. In the filed test, population size decreasd 7.6% for about 1 month.

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Observations of the nocturnal behavior of the German cockroach, Blattella germanica, were carried out using single or mixed populations of males, gravid females, ungravid females and nymphs.
In captivity adult males were very active, did not concentrate on the feeding site, and spread widely in the walking area. Gravid females, in contrast, were quite different in their moving pattern from males. The majority of them never came out to the walking area, and only a few individuals gathered around the feeding place. The behavior of the roaches was also observed in the mixed populations.
In a separate field study of capturing cockroaches by setting adhesive traps on the open space in a restaurant, the proportion of adult males, ungravid females and gravid females was 64%, 32%, 4%, respectively. The result was same as the above mentioned experiments.

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Since 1995, we have conducted the research for the control of Ororo-tabanidfly, Hirosia iyoensis at some mountainous areas in Toyama Prefecture, central part of Japan, where a great number of Ororo-tabanidflies occur every year.
The effect of traps baited with CO₂ gas to H. iyoensis was studied. These canopy traps were effective in mass-capturing Ororo- tabanidflies. The performance of pyrethroid insecticides and a repellent were also investigated. Pyrethrum extract, pyrethrin and prallethrin showed fast knock down effects against Ororo-tabanidflies. And, also deet had a repellent action.

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Rapid detection of the American cockroach by traps baited with (±) Periplanone- B, synthetic sex pheromone of the American cockroach, was conducted at flields of Okinawa, Taipei and Honolulu, and at arena tests in laboratory. Pheromone traps used only one night caught 14.2 times as many male American cockroaches as did the control traps. In the laboratory tests with males, 68% were caught in jar traps with pheromone, 6% in the control traps, and 26% were found in the shelter in 10 trials during 5 nights.
Ninety three % of the captured cockroaches were trapped within 4 hours from 7 p.m. In the laboratory tests with mixed sexes and stages significantly greater number of male adults were caught in pheromone traps. The synthetic (±) Periplanone-B can be used for rapid detection of the American cockroach.

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Red flour beetles were reared under unheated or less heated room conditions, using plain flour containing 10% dried yeast powder as their food. Nearly half of adults emerging later than August could overwinter once, but no adults could twice. Neither larvae nor pupae were able to overwinter, and no larvae emerged from food where adults were kept from September 30 to December 24, or from December 24 to April 13, suggesting that eggs were also killed by low temperature. Usually more than 50% of the new adults were found on paper shelters standing on the food before, during, and after overwintering. Once overwintered, however, most adults stayed in the food through the next September or later, suggesting that the old adults need less frequemt matings.

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Two kinds of marketed spices, cayenne-pepper powder (Shichimi-togarashi) and curry powder (Kare-ko), were tested as food for Indian meal moth larvae, Plodia interpunctella (H.). When eggs were introduced into newly purchased spices, no larvae developed. Even young 5th instar larvae placed on the spices could not develop, and died, in the newly purchased spices. After one or two months of air-exposed aging of the newly purchased spices, however, about 50% of introduced eggs (hatching larvae) grew, pupated, or emerged into adults in cayennepepper powder containers, but no larvae developed in the curry powder containers yet. After 6 months of aging of the newly purchased curry powder, one of 30 introduced 5th instar larvae could emerge into an adult. These results suggest that the newly purchased spices contained some factor(s) killing Indian meal moth larvae, and the factor(s) would fade out during the aging periods of the spices under the air-exposed conditions.

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[in Japanese]

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[in Japanese]

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Effect of two electromagnetic rodent repellers was tested in the laboratory against captive rats, Rattus norvegicus and R. rattus, and albino mice, Mus musculus. The efficacy was determined from thier bait consumption and behavior. These devices produced only negative results.

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Five drug-store beetles (three big and two small adults), Stegobium paniceim, were released into each of petri-dishes or sample tubes which contained different amounts of powdery food (9:1 mixture of plain flour and dried brewer's yeast) and were kept under 25℃ and 12L-12D conditions. When the height of food deposit in the container was 0.625mm, no F₁ adults were obtained. When the height was less than 1.4mm, F₁ adults were smaller than normal adults. All F₂ larvae entered diapause under these conditions. Unchilled diapause larvae required 6-10 months to become adults at 25℃. When chilled at 5℃ for two months, however, diapause larvae pupated and emerged into adults within one and half a month after returning to the room temperature conditions in May and June.

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[in Japanese]

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A predictive estimation of the population density of the hornets, Vespa was carried out using multiple regression in order to obtain a basic information of the countermeasure against the hornet.
The number of consultations from the citizen was used for the criterion variable.
The total rainfall in July of preceding year, and the average temperature in November of the preceding year and/or that in April of the same year, was selected for the explanatory variable. Three multiple regression models were statistically established based on the data accumulated from 1988 to 1994, from 1988 to 1995 and from 1988 to 1996.
The three multiple regression models, which established using two explanatory variables, i.e., the total rainfall in July and the average temperature in November of the preceding year, were found to give a high predictability, (coefficient of determination; 0.81〜0.83). The number of consultations predicted for 1997 were 3,530, 3,530 and 3,390, respectively.

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[in Japanese]

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