Biodegradable packaging buffers made from corn or wheat starch have replaced plastic foambuffers as packaging materials. The German cockroach, Blattella germanica, the smoky-brown cockroach, Periplaneta fuliginosa, and the brown-banded cockroach, P. brunnea consumed the biodegradable packaging buffers as food when they were kept in an arena with water, yet they hesitated to eat a urethane buffer. The cockroaches could survive and most of them could propagate for generations feeding on packaging buffer. Therefore, the biodegradable packaging buffers should be removed from factories immediately to avoid cockroach infestation.

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Seasonings powder infested by red-legged ham beetles was sieved on December 15th, 1998, and the insects were divided into three groups, adults, fully-grown larvae, and middle- to small-sized larvae. Each group was reared in a plastic container of 7.7 cm bottom diameter and 5.2 cm depth. Most (83.3%) of the adults died in winter before April 7, and 100% before July 20, 1999, without producing any offspring. A substantial number (40%) of the fully-grown larvae survived and emerged as adults between June 8th and 15th, and 19% of the middle- to small-sized larvae between June 8th and Sept. 8th, 1999. The new adults survived for about two months, 100% dying out before Nov. 4th. Most (92.9%) of the next generation adults emarged between Sep. 18th and Nov. 26th, and the rest between Dec. 24th, 1999 and Feb. 10th, 2000. These adults died in winter between Dec. 24th, 1999 and April 17th, 2000, in the same way as the adults obtained at the end of 1998 did. The adults produced their progenies larvae in the container, and new adults began to emerge between May 17th and 29th, and were continuing to emerge on July 10th, 2001, when the observation was stopped. These results indicate that the red legged ham beetle can repeat two generations in Central Japan, producing the first generation adults during May and June, the second generation adults during Sep., Oct. and Nov., and overwinters as fully-grown larvae.

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Viscosity of cockroach feces was peculiar to the cockroach species, no matter what kinds of foods consumed. The brown-banded cockroach, Periplaneta brunnea and the Japanese cockroach, P. japonica deposit solid feces on the floor of the test arena when they fed on mayonnaise, yogurt, condensed milk, banana or fermented soybean (Nattou). The feces of the smoky-brown cockroach, P. fuliginosa, the American cockroach, P. americana and the German cockroach, Blattella germanica tends to stick to the filter papers when they feed on the same above-mentioned foods. The feces of the latter three species has tendency to stick on the surfaces of filter papers. There were many feces when they fed on fiber-rich foods, such as banana or fermented soybean (Nattou) compared with being fed non-fiber foods. When they fed on water only, the feces were small and distorted.

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Turkistan cockroach, Blatta lateralis, nymphs of various stages of growth and male and female adults were collected from June through October in 2005 in a multi-floor warehouse in Aichi prefecture. They were captured from each floor, and were often collected together with the smoky-brown cockroach, Periplaneta fuliginosa. We considered that the colonies of B. lateralis could be established in this area and could become a harmful pest in central Japan.

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[in Japanese]

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The reaction of the Japanese termites Reticulitermes speratus colonized in Sapporo (Sap.) in low temperatures was compared with reactions of other local colonies (Akita, Tsukuba, Kagoshima) in Japan. Slowly lowering the temperature of a test tube from 20.0℃ to -4.0℃ gradually slowed the activity of all the test termites. Among the four colonies, Sap. was shown to have the widest temperature range in which "active behavior" was observed. The revival ratio of Sap. after "suspended animation" was higher than for the other colonies. The mortality rate of Sap. after over-wintering was 54.7%, while that of the other colonies exeeded 90%. During the five weeks of early spring, Sap. damaged a wood piece (steam-treated larch) more severely than the other colonies. These results suggest that Sap. has a higher cold resistance than other colonies (Akita, Tsukuba and Kagoshima).

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[in Japanese]

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