Kyushu University Academic Staff Educational and Research Activities Database
List of Papers
Keiji Takasu Last modified date:2022.09.15

Professor / Agronomy and Environmental Sciences / Department of Bioresource Sciences / Faculty of Agriculture

1. Ayaka Uke,Hiroki Tokunaga,Yoshinori Utsumi, Nguyen Anh Vu,Pham Thi Nhan,Nguyen Huu Hy,Le Huy Ham,Luis Augusto Becerra Lopez‑Lavalle,Manabu Ishitani,Nguyen Hung,Le Ngoc Tuan,Nguyen Van Hong,Ngo Quang Huy,Trinh Xuan Hoat,Keiji Takasu,Motoaki Seki,Masashi Ugaki, Cassava mosaic disease and its management in Southeast Asia, Plant Molecular Biology,, 2021.07.
2. #Nguyen Tuan, D., #Sam, L., #Zhang, C., @Nguyen Ngoc Bao, C., @Takano, S. I., @Takasu, K.,, Taro Colocasia esculenta as an alternative host plant for rearing cassava mealybug (Hemiptera: Pseudococcidae) and its parasitoid Anagyrus lopezi (Hymenoptera: Encyrtidae), Applied Entomology and Zoology,, 55, 355-359, 2020.08, So far, Phenacoccis manihoti (Hemiptera: Pseudococcidae) has been reared mainly with cassava. To explore alternative host plant for rearing of P. manihoti and its parasitoid Anagyrus lopezi De Santis (Hymenoptera: Encyrtidae), we examined suitability of taro Colocasia esculenta (L.) (Alismatales: Araceae) for rearing them in the laboratory, which was compared with that of cassava seedling. Either 50 newly hatched mealybug nymphs or parasitized third-instar mealybugs were reared on taro or cassava seedlings to examine immature development, fecundity and longevity of adults. Nearly 90% of P. manihoti reared on taro successfully developed to adults and they produced 230 eggs on average in their lifetime, while insects reared on cassava showed 95% survival and 250 eggs of lifetime fecundity. For A. lopezi, immature survival was 86% and they laid 140 eggs on average on taro, while it was 88% and 140 eggs on cassava. The results suggested that taro can be used for rearing of P. manihoti and its parasitoid A. lopezi..
3. Purnama Hidayat, Arini, Dwi Guntoro, Keiji Takasu, William A. Overholt, Biology and rearing of the cogongrass gall midge, Orseolia javanica Kieffer & Docters van Leeuwen-Reijnvaan (Diptera: Cecidomyiidae), bioRxiv, 2020.02, Imperata cylindrica (L.) Beauv. (Poaceae) is one of the most harmful weeds in the world because of its ability to spread and form high density, monospecific stands that exclude other vegetation. The cogongrass gall midge, Orseolia javanica Kieffer & Docters van Leeuwen-Reijnvaan (Diptera: Cecidomyiidae), is a stem galling insect that is only known to develop in cogongrass and has only been found on the island of Java in Indonesia. The midge attacks very young shoots, which stimulates abnormal growth, resulting in the formation of a purplish, elongate stem gall tappered to a point at the apical end. The aim of the current research was to describe the biology of the midge and develop a rearing method. Orseolia javanica completed its life cycle in 12-38 days with average egg, larval, and pupal periodes of 4.0 +/- 0.0, 13.5 +/- 3.8, and 8.6 +/- 6.6 days (mean +/- SD), respectively. Mated female, unmated female, and male longevities were 1.7 +/- 0.47, 1.2 +/- 0.41, and 1.0 +/- 0.00 days (mean +/- SD). Galls began to appear 29 days after larval infestation, and stem death coincided with emergence of the adult midge. The midge may have potential for biological control of cogongrass if future studies confirm a restricted host range..
4. Shun ichiro Takano, Keiji Takasu, Food deprivation increases reproductive effort in a parasitoid wasp, Biological Control, 10.1016/j.biocontrol.2019.03.010, 133, 75-80, 2019.06, Life history theory predicts that animals should increase their current reproductive effort as the probability of survival to the next reproductive opportunity decreases. We studied the effects of food depletion on life history and oviposition behavior in the egg parasitoid Paratelenomus saccharalis (Hymenoptera: Platygastridae) to determine if the parasitoid alters its reproductive strategy based on life expectancy. We first examined survivorship and reproductive effort of females provided only with water (i.e. starved) and females fed honey. Fed females lived up to 40 days, whereas starved females lived only up to 4 days. Fed females produced more offspring during life and had a higher net reproductive rate, i.e. R
, compared to starved females. Starved females did produce more offspring on the first day of emergence, however, and the intrinsic rate of natural increase, i.e. r
, did not differ between honey-fed and starved females. We further observed oviposition behavior in response to food availability during 24 h on the first day of emergence to determine the mechanism by which starved females increased reproductive output. Results showed that starved females oviposited more frequently than honey-fed females, and that the time required for a single oviposition was shorter for starved females. These results revealed that starved females had higher oviposition rates on the first day of emergence, leading to the similar r
of starved and fed females. This indicates that P. saccharalis altered their oviposition behavior to maximize their fitness under food-depleted conditions..
5. Keiji Takasu, Jemimah N. Ndabarua, Hieu Thi Pham, Shun ichiro Takano, Pupal-adult parasitism of the coconut hispine beetle by the koinobiont pupal parasitoid Tetrastichus brontispae, Biological Control, 10.1016/j.biocontrol.2018.07.013, 126, 90-96, 2018.11, Pupal parasitoids are considered to be idiobionts. However, some pupal parasitoids do not seem to kill or paralyze hosts at oviposition, including Tetrastichus brontispae, an endo-pupal parasitoid of Brontispa longissima. We conducted laboratory experiments to determine if T. brontispae parasitizes pupal hosts with a koinobiont developmental strategy. For this to be the case, its immatures would have to develop during the host transition from pupa to adult and in adulthood. With 0-d-old to 5-d-old pupal hosts, the T. brontispae females stung hosts of all ages with over 80% frequency. When the pupal hosts were parasitized, there were two modes of parasitism: pupal parasitism and pupal-adult parasitism. For pupal hosts that were parasitized, the majority showed a typical pupal parasitism, involving first the mummification of parasitized pupae and then the development of the parasitoid immatures within and emergence from these mummified pupae. However, the parasitized pupae that did not become mummified developed to host adults in which the parasitoid immatures developed, indicating pupal-adult parasitism. When parasitized pupal hosts were mummified, the 0-d-old to 3-d-old pupae were more likely than the older pupae to be mummified and had a greater number of parasitoid adults produced per host. The pupal-adult parasitism was not as successful. The parasitoid adults only successfully emerged from two host adults, which were parasitized as 2-d-old pupae, and one host adult parasitized as a 3-d-old pupa. The parasitoid eggs laid in 4-d-old and 5-d-old pupae continued to develop during and after the host transition from the pupa to adult. However, when the host adults died within 10 days after emergence, all the parasitoids died without completing their development. These results suggest that T. brontispae is a koinobiont parasitoid that successfully parasitizes young pupal hosts mainly through host mummification and rarely through pupal-adult parasitism. The fact that many parasitized 4-d-old or 5-d-old pupae died at the pupal or adult stage without producing any parasitoids, may also suggest that, under natural conditions, the pupal and adult mortality of B. longissima resulting from parasitism by T. brontispae is significant..
6. Hiroki Tokunaga, Tamon Baba, Manabu Ishitani, Kasumi Ito, Ok Kyung Kim, Le Huy Ham, Hoang Khac Le, Kensaku Maejima, Keiko T. Natsuaki, Nguyen Van Dong, Hy Huu Nguyen, Nien Chau Nguyen, Nguyen Anh Vu, Hisako Nomura, Motoaki Seki, Pao Srean, Hirotaka Tanaka, Bunna Touch, Hoat Xuan Trinh, Masashi Ugaki, Ayaka Uke, Yoshinori Utsumi, Prapit Wongtiem, Keiji Takasu, Correction
Sustainable management of Invasive Cassava Pests in Vietnam, Cambodia, and Thailand [Crop Production under Stressful Conditions (2018)] DOI: 10.1007/978-981-10-7308-3_8, Crop Production under Stressful Conditions Application of Cutting-edge Science and Technology in Developing Countries, 10.1007/978-981-10-7308-3_8, E1, 2018.08, The author Dr. Shigeto Namba has withdrawn his authorship from the chapter. Also, the authors H. Nomura, H. Tanaka, and K. Takasu have updated their affiliation as below:..
7. Hiroki Tokunaga, Tamon Baba, Manabu Ishitani, Kasumi Ito, Ok Kyung Kim, Le Huy Ham, Hoang Khac Le, Kensaku Maejima, Keiko T. Natsuaki, Nguyen Van Dong, Hy Huu Nguyen, Nien Chau Nguyen, Nguyen Anh Vu, Hisako Nomura, Motoaki Seki, Pao Srean, Hirotaka Tanaka, Bunna Touch, Hoat Xuan Trinh, Masashi Ugaki, Ayaka Uke, Yoshinori Utsumi, Prapit Wongtiem, Keiji Takasu, Sustainable management of invasive cassava pests in Vietnam, Cambodia, and Thailand, Crop Production under Stressful Conditions Application of Cutting-edge Science and Technology in Developing Countries, 10.1007/978-981-10-7308-3_8, 131-157, 2018.08, JST-JICA 地球規模課題対応国際科学技術協力プログラム(SATREPS) ベトナム、カンボジア、タイにおけるキャッサバの侵入病害虫対策に基づく持続的生産システムの開発と普及(2015-2020年度、総額5億円)の研究者代表として、ベトナム、カンボジア、タイ、日本の4か国 計11研究機関による国際共同研究を実施している。.
8. Shunichiro Takano, Keiji Takasu, Matias Tavares, Marcal Gusmao, Acacio Cardoso Amaral, Differences in invasiveness between two cryptic species of the coconut beetle Brontispa longissima in Timor-Leste, Biological Invasions, 10.1007/s10530-017-1394-4, 19, 6, 1839-1851, 2017.06, Brontispa longissima (Coleoptera: Chrysomelidae) is a serious pest of coconut palm, and the species contains two cryptic species: the “Asian clade” is distributed over a wide area, including Asia and the Pacific region, whereas the “Pacific clade” is distributed in a limited area. Recent invasions and outbreaks have only been reported for the Asian clade, suggesting that invasive ability may differ between the clades. To reveal differences in invasiveness, we investigated the damage potential on coconut palm and range expansion of the two clades in Timor-Leste, where both clades are present. Distribution of the clades and of severely damaged trees indicated that range expansion and outbreaks have occurred for the Asian clade but not for the Pacific clade. The Asian clade attacked trees taller than 10 m, whereas the Pacific clade seldom attacked these trees. The preference for the taller trees, which are more abundant, can facilitate range expansion and outbreaks of the Asian clade. The beetle has spread through areas where coconut palms are continuously available, but have not expanded their distribution where coconut palms are separated by large gaps. This indicates that areas free of coconut palm could serve as buffer zones to prevent spread of this beetle..
9. Keisuke Hoshino, Taro Adati, Dawn M. Olson, Keiji Takasu, Seasonal occurrence and interspecific interactions of egg parasitoids of megacopta cribraria (heteroptera
Plataspidae) in Japan, Environmental Entomology, 10.1093/ee/nvx060, 46, 3, 487-493, 2017.06, We conducted a field study to determine seasonal egg parasitism rates of the kudzu bug Megacopta cribraria (F.) on the kudzu plant, Pueraria Montana (Lour.) Merr. var. lobata (Willd.) Maesen et Almeida ex Sanjappa and Pradeep, in Tokyo, Japan, during the period from May 2014 to September 2014. The eggs of M. cribraria per 1 m2 of kudzu at four locations in Tokyo were collected weekly and parasitism rates were assessed. Eggs of M. cribraria were laid on the kudzu plant from May to September. Megacopta cribraria eggs were parasitized by two parasitoid species, Paratelenomus saccharalis (Dodd) and Ooencyrtus nezarae Ishii. Paratelenomus saccharalis first appeared in May, and its parasitism rates peaked in July and September. Ooencyrtus nezarae first appeared in June and its parasitism rates peaked in July. Except for one location which could not be statistically analyzed because of the small sample size, occurrence of parasitism by P. saccharalis and O. nezarae in M. cribraria egg masses was independent at one location and positively associated at two locations, suggesting that the use of host egg masses by P. saccharalis and O. nezarae is not mutually exclusive. Parasitism rates by P. saccharalis and O. nezarae were significantly lower for egg masses parasitized by both species than for those parasitized by a single species. The proportion of males among O. nezarae progeny was significantly higher for egg masses parasitized by O. nezarae together with P. saccharalis than for those parasitized by O. nezarae alone. These results suggest that parasitism of host egg masses by the two species is influenced by their interspecific interactions..
10. Shunichiro Takano, Midori Tuda, Keiji Takasu, Naruto Furuya, Yuya Imamura, Sangwan Kim, Kosuke Tashiro, Kazuhiro Iiyama, Matias Tavares, Acacio Cardoso Amaral, Unique clade of alphaproteobacterial endosymbionts induces complete cytoplasmic incompatibility in the coconut beetle, Proceedings of the National Academy of Sciences of the United States of America, 10.1073/pnas.1618094114, 114, 23, 6110-6115, 2017.06, Maternally inherited bacterial endosymbionts in arthropods manipulate host reproduction to increase the fitness of infected females. Cytoplasmic incompatibility (CI) is one such manipulation, in which uninfected females produce few or no offspring when they mate with infected males. To date, two bacterial endosymbionts, Wolbachia and Cardinium, have been reported as CI inducers. Only Wolbachia induces complete CI, which causes 100% offspring mortality in incompatible crosses. Here we report a third CI inducer that belongs to a unique clade of Alphaproteobacteria detected within the coconut beetle, Brontispa longissima. This beetle comprises two cryptic species, the Asian clade and the Pacific clade, which show incompatibility in hybrid crosses. Different bacterial endosymbionts, a unique clade of Alphaproteobacteria in the Pacific clade and Wolbachia in the Asian clade, induced bidirectional CI between hosts. The former induced complete CI (100% mortality), whereas the latter induced partial CI (70% mortality). Illumina MiSeq sequencing and denaturing gradient gel electrophoresis patterns showed that the predominant bacterium detected in the Pacific clade of B. longissima was this unique clade of Alphaproteobacteria alone, indicating that this endosymbiont was responsible for the complete CI. Sex distortion did not occur in any of the tested crosses. The 1,160 bp of 16S rRNA gene sequence obtained for this endosymbiont had only 89.3% identity with that of Wolbachia, indicating that it can be recognized as a distinct species. We discuss the potential use of this bacterium as a biological control agent..
11. Jean Philippe Parent, Keiji Takasu, Jacques Brodeur, Guy Boivin, Time perception-based decision making in a parasitoid wasp, Behavioral Ecology, 10.1093/beheco/arw171, 28, 3, 640-644, 2017.05, The capacity of animals to measure time and adjust their behaviors accordingly has been a topic of interest in vertebrates, but little evidence is currently available for insects. This capacity has yet to be properly investigated in parasitoid wasps, even though they are frequently used to test ecological models. Here, using associative learning between odors and time intervals, we show that the parasitoid wasp Microplitis croceipes (Hymenoptera: Braconidae) has the capacity to measure time. When released in a wind tunnel, females flew toward an odor associated with the time interval they had just experienced. We also found that reducing energy expenditure by restraining parasitoid wasp movement during the training interval prevented time perception. This serves as experimental evidence of time perception in a parasitoid wasp, provides both a rare example of learning associated to a time interval in an insect and a mechanism by which these animals could optimize their behaviors, as well as suggesting a role for energy expenditure in its time perception mechanism..
12. William A. Overholt, Purnama Hidayat, Bruno Le Ru, Keiji Takasu, John A. Goolsby, Alex Racelis, A. Millie Burrell, Divina Amalin, Winnifred Agum, Mohamed Njaku, Beatrice Pallangyo, Patricia E. Klein, James P. Cuda, Potential Biological Control Agents for Management of Cogongrass (Cyperales
Poaceae) in the Southeastern USA, Florida Entomologist, 10.1653/024.099.0425, 99, 4, 734-739, 2016.12, Cogongrass, Imperata cylindrica (L.) Palisot de Beauvois (Cyperales: Poaceae), is a serious invasive weed in the southeastern USA. Surveys for potential biological control agents of cogongrass were conducted in Asia and East Africa from 2013 to 2016. Several insect herbivores were found that may have restricted host ranges based on field collection data and life histories. Stemborers in the genus Acrapex (Lepidoptera: Noctuidae) were collected from cogongrass in Tanzania, Uganda, and Japan. In the Philippines, larvae of Emmalocera sp. (Lepidoptera: Pyralidae) and Chilo sp. (Lepidoptera: Crambidae) were found boring in cogongrass. Cecidomyiid midges were found in both Japan and Indonesia. A Japanese midge identified as a Contarinia sp. (Diptera: Cecidomyiidae) caused deformation of the stem, whereas the Indonesian midge Orseolia javanica Kieffer & van Leeuwen-Reijinvaan (Diptera: Cecidomyiidae) induced the formation of a basal stem gall. Previous research suggested that the host range of O. javanica was restricted to cogongrass..
13. Shunichiro Takano, Keiji Takasu, Ability of Megacopta cribraria (Hemiptera
Plataspidae) to Cling to Different Surfaces against Extreme Wind, Journal of Insect Behavior, 10.1007/s10905-016-9557-1, 29, 3, 256-261, 2016.05, The kudzu bug, Megacopta cribraria (Fabricius), is native to Asia but recently invaded the US and is expanding its distribution rapidly. To assess the probability of this bug traveling by attaching to the exteriors of fast-moving vehicles, we investigated the ability of M. cribraria adults to cling to stages with different surfaces (cloth, metal, or glass) against extreme airflows in a transparent acrylic tube connected to a vacuum cleaner. On the stages with cloth and metal, insects remained on the stages at 100 km/h wind speed. Estimated wind velocities required to blow 50 % of insects from the stages within 1 min were more than 100 km/h (cloth); 60 km/h (metal); and 40 km/h (glass) for males and 100 km/h (cloth); 50 km/h (metal); and 30 km/h (glass) for females. Together with frequent observations of attached M. cribraria on vehicle exteriors in the field, our results indicate a fairly high probability of range expansion of this species by attachment to vehicles..
14. K. Takasu, Y. Yoshiyasu, A. M. Burrell, P.E. Klein, A. Racelis, J. A. Goosby, W. A. Overholt, Acrapex azumai Sugi (Lepidoptera: Noctuidae) as a possible biological control agent of the invasive weed Imperata cylindrica (L.) Beauv. (Poaceae) in the United States, Lepidoptera Science, 65, 1, 30-35, 2014.04.
15. J. K. Makatiani, H. K. Le, D. M. Olson, F. L. Wäckers, Keiji Takasu, An acquired distaste
Sugar discrimination by the larval parasitoid Microplitis croceipes (Hymenoptera: Braconidae) is affected by prior sugar exposure, Journal of Experimental Biology, 10.1242/jeb.091843, 217, 10, 1692-1700, 2014.01, We examined gustatory responses of the larval parasitoid Microplitis croceipes to determine whether the adults discriminate among common sugars, including fructose, glucose, maltose and sucrose, found in plants. When given single sugar solutions of sucrose, glucose, fructose and maltose at concentrations of 0.008-2.0 mol l-1, the estimated concentrations at which 50% of wasps initiated feeding ranged between 0.054 and 0.085 mol l-1 for sucrose, glucose and fructose, which was significantly lower than for maltose. Wasps showed a strong decrease in feeding time for maltose or fructose following a brief exposure to other sugars, suggesting that wasps can distinguish maltose and fructose from the other sugars tested. The higher acceptance threshold and short feeding time in the case of maltose appears adaptive in light of the relatively poor nutritional quality of the sugar in the longevity trial. The pronounced feeding inhibition seen for fructose following exposure to other sugars is not linked with lower nutritional performance. This feeding inhibition was even seen in wasps that had fed on glucose at the lowest acceptance threshold (0.031 mol l-1) and persisted for 24 h. This study is the first to show feeding inhibition of otherwise phagostimulant sugars such as maltose and fructose after gustatory stimulation on other sugars..
16. Keiji Takasu, Yutaka Yoshiyasu, Millie Burrell, William Overholt, Acrapex azumai Sugi (Lepidoptera, Noctuidae) as a possible biological control agent of the invasive weed Imperata cylindrica (L.) Beauv. (Poaceae) in the United States, Lepidopteran Science, 65, 1, 30-35, 2014.
17. Keiji Takasu, Reproductive biology of Ooencyrtus nezarae, an egg parasitoid of the kudzu bug Megacopta cribraria in Japan, Entomology 2014 TMP's, P-IE Section: Biological Control A, 2014.
18. J. K. Makatiani, A. Y. Bruce, F. Schulthess, Keiji Takasu, Reproductive strategies of the larval parasitoid Microplitis croceipes
, Entomologia Experimentalis et Applicata, 10.1111/eea.12099, 148 , 3, 223-233, 2013.09.
19. Shunichiro Takano, Keiji Takasu, Mika Murata, Nguyen Thi Huong, Satoshi Nakamura, Comparative developmental and reproductive biology of geographical populations from two cryptic species in Brontispa longissima (Coleoptera
Chrysomelidae), Entomological Science, 10.1111/ens.12007, 16, 3, 335-340, 2013.07, Brontispa longissima is a serious pest of the coconut palm Cocos nucifera, presumed to have originated in Papua New Guinea and Indonesia. It recently invaded Southeast and East Asia, where outbreaks have been reported. Mitochondrial DNA analysis reveals two cryptic species in B.longissima: one is distributed over a wide area including Asia and the Pacific region (the Asian clade) and the other in a limited area in the Pacific region (the Pacific clade). Recent invasions and outbreaks have been reported only from the area where the Asian clade has been found, suggesting that this clade has become a pest in Asia. To infer if the Asian clade has the ability to establish, spread and outbreak in novel habitats more effectively than the Pacific clade, we compared life-history traits between the two populations of different clades. The net reproduction rate (R0) was 130.0 and 94.0, the mean length of a generation (T) was 57.7 and 54.7 days, and the intrinsic rate of natural increase (r) was 0.084 and 0.083 per day for the population from Ishigaki Island, Japan (ISH) (the Asian clade) and for the population from Papua New Guinea (PNG) (the Pacific clade), respectively. Although the difference in r was little, the simulated population growth showed that the ISH population can be 1.6 times larger than that of the PNG after ten generations. The rapid population growth of the Asian clade would be partly responsible for its establishment, spread and frequent outbreaks in Asia..
20. Shun-ichiro Takano, Atsushi Mochizuki, Keiji Takasu, Kazuhiko Konishi, J. C. Alouw, D. S. Pandin, Satoshi Nakamura, Rapid discrimination of two cryptic species within Brontispa
longissima (Gestro) (Coleoptera: Chrysomelidae) by PCR–RFLP, Journal of Pest Science, 10.1007/s10340-012-0474-6, 86, 2, 151-155, 2013.06.
21. Keiji Takasu, Olfactory associative learning of mate searching cues by the larval parasitoid Microplitis croceipes, The third International Entomophagous Insects Conference, 2013.06.
22. Ruberson, John R., Keiji Takasu, Buntin, G. David, From Asian curiosity to eruptive American pest: Megacopta cribraria (Hemiptera: Plataspidae) and prospects for its biological control, Applied Entomology and Zoology, 10.1007/s13355-012-0146-2, 48, 1, 3-13, 2013.02.
23. Takano, S., Takasu, K., Ichiki, R. T., Nakamura, S, Cold tolerance of the coconut hispine beetle Brontispa longissima (Coleoptera: Chrysomelidae) in Japan, Applied Entomology and Zoology, 10.1007/s13355-012-0105-y, 47, 3, 173-180, 2012.08.
24. H.T. Nguyen, T.T. Oo, R.T. Ichiki, S. Takano, M. Murata, K. Takasu, K. Konishi, S. Tunkumthong, N. Chomphookhiaw & S. Nakamura, Parasitisation of Tetrastichus brontispae (Hymenoptera: Eulophidae), a biological control agent of the coconut hispine beetle Brontispa
longissima (Coleoptera: Chrysomelidae), Biocontrol Science and Technology,, 22, 8, 955-968, 2012.07.
25. Shun-ichiro TAKANO, Keiji TAKASU, Tsutomu FUSHIMI, Ryoko T. ICHIKI and Satoshi NAKAMURA, Life history traits and damage potential of an invasive pest Brontispa longissima (Coleoptera: Chrysomelidae) on
Satakentia liukiuensisens, Entomological Science, 10.1111/j.1479-8298.2011.00506.x, 15, 238–245, 2012.04.
26. Takano, S., Takasu, K., Ichiki, RT., Fushimi, T., and Nakamura, S, Induction of host-plant preference in Brontispa longissima (Gestro) (Coleoptera: Chrysomelidae), Journal of Applied Entomology, 135, 1-7, 2011.04.
27. Takano, S., Mochizuki, A., Konishi, K., Takasu, K., and Nakamura, S. , Two cryptic species in Brontispa longissima (Colenoptera: Chrysomelidae): evidence from mitochondrial DNA analysis and crosses between the two nominal species., Annals of Entomological Society of America, 104, 121-131, 2011.03.
28. Takano, S., Sugeno, S., Mochizuki, A., Nakamura, S. and Takasu, K., Occurrence and distribution of the coconut hispine beetle Brontispa longissima in the Southwest islands of Japan, Proceedings of 7th International AFAS Joint Symposium between Korea and Japan, 149-154, 2010.11.
29. Ai Yamashita and Keiji Takasu, Suitability of potential host plants in Japan for immature development of the coconut hispine beetle, Brontispa longissima Gestro (Coleoptera: Chrysomelidae) , JARQ, 44, 2, 2010.04.
30. Andrei Alyokhin , Jacqueline Makatiani and Keiji Takasu, Insecticide Odour Interference with Food-Searching Behaviour of Microplitis croceipes (Hymenoptera: Braconidae) in a Laboratory Arena, Biocontrol Science and Technology, 2010.04.
31. Kyawt San Dar Aung, Keiji Takasu, Takatoshi Ueno and Masami Takagi, Effect of temperature on egg maturation and longevity of the egg parasitoid Ooencyrtus nezarae (Ishii) (Hymenoptera: Encyrtidae), J. Fac. Agr. Kyushu Univ., 55, 1, 87-89, 2010.04.
32. Takasu, K., Takano, S., Konishi, K., and Nakamura, S., An invasive pest Brontispa longissima (Gestro) (Coleoptera: Chrysomelidae) attacks an endemic palm in the Yaeyama Islands, Japan, Applied Entomology and Zoology, 2010.01.
33. Ai Yamashita, Amporn Winotai, Keiji Takasu, Use of mature leaves of coconut palm and the cattail for laboratory rearing of the coconut leaf beetle Brontispa longissima, Journal of Agricultural Science and Technology at CNU, 2009.06.
34. Huong Lan Bui, Keiji Takasu, Learning of narcotic odors by a parasitoid , Journal of Agricultural Science and Technology at CNU, 2009.06.
35. Ah Nge Htwe, Masami Takagi and Keiji Takasu, Development of Myanmar strain of Cotesia vestalis (Hymenoptera: Braconidae) on its host plutella xylostella (Lepidoptera: Plutellae) at different temperatures, J. Fac. Agr. Kyushu Univ., 53 (2) 441-446, 2009.03.
36. Ah Nge Htwe, Keiji Takasu and Masami Takagi, Laboratory rearing of the diamondback moth Plutella xylostella (L.) (Lepidoptera: Plutellidae) with artificial diet , J. Fac. Agr. Kyushu Univ., 54 (1) 147-151, 2009.03.
37. Ai Yamashita, Keiji Takasu, Suitability of potential host plants in Japan for immature development of the coconut hispine beetle, Brontispa longissima Gestro (Coleoptera: Chrysomelidae) , Bulletin of the Institute of Tropical Agriculture Kyushu University, vol. 32, 2009.03.
38. Keiji Takasu and Satoshi Nakamura, Life history of the tick parasitoid Ixodiphagus hookeri (Hymenoptera: Encyrtidae) in Kenya, Biological Control, 2008.05.
39. Keiji Takasu, Kazuo Ogata, Ah Nge Htwe, Giang Thi Thu Ho and Masami Takagi, Winter crop problems associated with the introduction of hybrid rice: protection of crucifer crops against DBM, Proceedings of the JSPS International Seminar 2007, Hybrid rice and agroecosystem, 205-209, 2007.11.
40. Konishi K, Nakamura S, and Takasu K , Invasion of the coconut hispine beetle, Brontispa longissima: Current situation and control measures in Asia., Proceedings of International Symposium for Invasive Alien Species in Monsoon Asia: , pp. 1-7., 2007.10.
41. Keiji Takasu and Le K. H., The larval parasitoid Microplitis croceipes oviposits in conspecific adults., Naturwissenschaften 94:200-206., Naturwissenschaften 94:200-206., 2007.03.
42. Keiji Takasu, Rains R. C. and Lewis, W. J., Comparison of detection ability of learned odors between males and females in the larval parasitoid Microplitis croceipes (Hymenoptera: Braconidae)., Entomologia experimentalis et applicata, Entomologia. Exp. Appli. 122: 247-251., 2007.03.
43. Keiji Takasu, Importance of multidisciplinary research for insect pest management., Inst. Trop. Agric. Kyushu Univ., 28:43-49., 2005.12.
44. Keiji Takasu, Helicoverpa armigera as an alternative host of the larval parasitoid Microplitis croceipes (Hymenoptera: Braconidae), Applied Entomology and Zoology, 10.1303/aez.2005.679, 40, 4, 679-686, 2005.11.
45. D.M. Olson, G. C. Rains, T. Meiners, K. Takasu, M. Tertuliano, J. H. Tumlinson, F. L. Wackers, and W. J. Lewis, Parasitic wasps learn and report diverse chemicals with unique conditionable beehaviors, Chemical Senses, 10.1093/chemse/28.6.545, 28, 6, 545-549, 2003.08.
46. Olson, D. M., Lewis, W. J., and Keiji Takasu, Interactive-web of factors governing effective natural enemy foraging behavior. Overview of food resources as a critical component., International Symposium on Biological Control of Arthropods., pp389-397..