3 0 0 0 OA ヒトスジシマカはシマウマ縞を忌避するか
- 著者
- 佐々木 均 秦 和寿 野沢 森生 橋場 利雄
- 出版者
- 日本衛生動物学会
- 雑誌
- 衛生動物 (ISSN:04247086)
- 巻号頁・発行日
- vol.71, no.4, pp.329-331, 2020-12-25 (Released:2020-12-17)
- 参考文献数
- 26
The role of zebra stripes is considered to be defensing from blood sucking by insects, such as tsetse flies and tabanid flies, those perform actively host-seeking flight. Aedes albopictus is opportunistically blood sucker, so, the reaction to zebra stripes may be different from such flies. Thus, we investigated the reaction of A. albopictus to the rugs of three color patterns, black, white, and zebra stripes. During the sunny days on August and September, 2019 with three different times in a day (morning, daytime, and evening), we counted the number of mosquitoes landed on the rugs on human decoy at a park in Tokyo. Significant difference (p<0.05) was found in the total number of mosquitoes landed on the three types of rugs, while no significant difference (p>0.05) was found in the numbers of mosquitoes landed on the rugs at each observation time. The number of A. albopictus which landed on the black-colored rug was two times more than that of a mosquito flying around the face of human decoy, while those on the rugs of white color and zebra stripes were a half and only 3% of those flying around the face of human decoy, respectively. The lured A. albopictus landed smoothly on the black rug, but the landings were not smooth on the zebra-striped rug. It was revealed that A. albopictus avoids zebra stripes as same as tsetse flies and tabanid flies.
2 0 0 0 IR 時計装置捕蝿器ハイトリックの防虫具史的検討
Four tanks, labeled A, B, C, and D, containing 750 liters of water, were placed outdoors near the laboratory. Breeding of Culex pipiens pallens was found in each tank in early June, 1972. Twenty guppies, or 10 mature pairs, were introduced in two of the tanks, B and C, on 9 June 1972. Tank B was then treated with fenitrothion 1ppm, tank C remained untreated. Tank D was treated with fenitrothion 1ppm on the same day, and tank A, the control tank, received neither guppies nor fenitrothion. The observation for each tank was conducted using a ladle to count the larvae and pupae densities every two or three days. Also counts of total number of egg rafts on the water surface were made on the same day. These observations were made until the end of September. According to the results, the larvae and pupae dramatically disappeared on the fourth day after fenitrothion treatment in both tanks B and D. In the case of tank D, the chemical treatment had to be repeated five times during a two-month period due to the outbreak of larvae every 10 or 20 days. Tank B, however, received no additional chemical treatment after the initial treatment because of the presences of the guppies. A number of pupae was observed for three weeks after introduction of guppies to tank C, but all pupae had disappeared by the end of this period. More than 100 rafts a day of oviposition were observed in tanks A and D. However, no rafts were recognized from tanks B and C, except for very few days during the peak time of oviposition activity of mid-summer. As Part II of the present report series showed, these egg rafts were eaten by guppies in each tank. Thus, in tanks B and C no adult mosquitoes emerged throughout the summer season.