Kobayashi M.,Tokyo University of Agriculture and Technology |
Murai T.,Tokyo University of Agriculture and Technology |
Murai T.,Utsunomiya Universityz
Japanese Journal of Applied Entomology and Zoology | Year: 2012
Development and reproduction of five populations of foxglove aphid, Aulacorthum solani (Kaltenbach), were investigated in nine soybean cultivars. Significant differences were observed in the development duration, aphid fecundity and the intrinsic rate of the natural increase of the aphid populations reared on the soybean cultivars. A delay in aphid development and a decrease in aphid fecundity were observed in all aphid populations reared on 'Adams,' an aphid-resistant soybean cultivar. In the Tochigi aphid population reared on 'William82,' a soybean cultivar that is susceptible to soybean aphid, a marked delay in aphid development was observed. In addition, aphid fecundity decreased and the intrinsic rate of the natural increase was very low. No resistance was observed in the four remaining aphid populations. The Toyama and Hokkaido populations exhibited similar patterns of development and reproduction when reared on the nine soybean cultivars. Thus, in order to assess the development of aphid resistance in soybean cultivars, the findings of this study suggest that the biological performance of aphids on soybean cultivars should be investigated using other aphid populations from different locations and biotypes.
Higeta A.,Utsunomiya Universityz |
Yoshida K.,Utsunomiya Universityz |
Hagane T.,Utsunomiya Universityz |
Hashimoto T.,Utsunomiya Universityz
Nihon Kikai Gakkai Ronbunshu, C Hen/Transactions of the Japan Society of Mechanical Engineers, Part C | Year: 2011
In this paper, we propose a four-bar linkage mechanism representing competition and cooperation. For this purpose, we propose a Single Bistabile Pendulum (SBP) mechanism of simple mechanism that have bistability by magnetic force and ferromagnetic cam. And we propose a four-bar linkage mechanism that have quadri-stability, connected the pendulum points of two SBP mechanisms by link. We obtain a basin of attraction of the four-bar linkage mechanism experimentally. Moreover, we derive a analysis model of the four-bar linkage mechanism, and obtain a basin of attraction of the analysis model numerically. Then, we compare a basin of attraction of the four-bar linkage mechanism with the analysis model. The result shows that the analysis model is suitable as a analysis model of the four-bar linkage mechanism. © 2011 The Japan Society of Mechanical Engineers.