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Abstract: This Letter describes 2-(2-(dioctylamino)-2-oxoethyl-amino)-2-oxoethoxyl (DOAOE)-tuned self-assembly of vesicles from rigid macrocycles and foldamer-like oligomers. The molecules are prepared through the formation of reversible hydrazone bonds from aldehyde and benzo-hydrazide precursors, which are further facilitated by intramolecular N⋯H–O hydrogen bonding. SEM, AFM, and fluorescent encapsulation studies reveal that the molecules all self-assemble into vesicular structures in methanol, while similar molecules bearing the triethylene glycol or n-decyl chains do not. The results illustrate that DOAOE is robust in promoting the formation of vesicles for aromatic systems in polar solvents. [Copyright &y& Elsevier]

The oriental armyworm, Mythimna separata (Walker) (Lepidoptera: Noctuidae), is a notorious migratory pest of cereal crops. Pyemotes zhonghuajia Yu, Zhang & He (Prostigmata: Pyemotidae) is an ectoparasitic mite with great potential in controlling many species of Lepidoptera, Coleoptera, and Homoptera. To evaluate the control efficiency of P. zhonghuajia on M. separata, we tested how initial density (1, 5, 10, or 20 mites) of P. zhonghuajia affected the mortality of oriental armyworm and the number of P. zhonghuajia fed upon individual hosts, and also determined the diameter growth of the opisthosoma and reproduction of P. zhonghuajia at different life stages of M. separata. Our results show that differing densities of P. zhonghuajia could significantly affect the mortality rate of different life stages of M. separata and the recruitment number of P. zhonghuajia on hosts, and there were significant differences in the development and reproduction parameters of P. zhonghuajia on different immature stages of M. separata. A single P. zhonghuajia could cause at least a 50% mortality rate of M. separata first to third instar larvae within 48 h. At higher density of 20 P. zhonghuajia, 100% of first to fourth and 30% of fifth instar larvae of M. separata were killed within 24 h. All prepupae and pupae of M. separata died when they were exposed to 10 and 20 P. zhonghuajia, respectively. In addition, density of P. zhonghuajia significantly influenced their adult recruitment of the body surface of M. separata. Pyemotes zhonghuajia could only complete development and reproduction on M. separata eggs, prepupae and pupae. However, the longevity, opisthosoma size and fecundity of P. zhonghuajia paralyzed on prepupae and pupae were significantly higher than those on eggs. In conclusion, P. zhonghuajia might be a suitable biological control agent against the oriental armyworm, and M. separata prepupae and pupae may be used as alternative prey for the mass rearing of P. zhonghuajia. [ABSTRACT FROM AUTHOR]

Starvation is defined as a failure to ingest and digest food under some extrinsic limitation. Starvation could induce some behavioral consequences, such as searching, movement, parasitism efficiency of arthropods. In this study, we evaluated the hunger tolerance and movement rates of Pyemotes zhonghuajia (Trombidiformes: Pyemotidae) on corn and sorghum leaves, and observed the time of P. zhonghuajia biting Spodoptera frugiperda (Lepidoptera: Noctuidae) and the lethal efficiency of P. zhonghuajia on S. frugiperda under different starvation periods (6 h, 12 h, 24 h, 48 h, 72 h and 96 h). The results showed that without host the survival rates of P. zhonghuajia were significantly reduced over the 96 h. Starvation significantly increased the movement rates of P. zhonghuajia on the sorghum and corn leaves with the starvation periods increasing from 6 to 24 h. When starved for 12 h, P. zhonghuajia significantly reduced the time spent biting S. frugiperda. Proper hunger in P. zhonghuajia caused a 100% mortality rate in S. frugiperda within 2 hours, while a 96-h starved P. zhonghuajia parasited S. frugiperda for 16 hours to achieve a 100% mortality rate. In conclusion, a shorter period of starvation (24 h) improved the movement rates and lethal efficiency of P. zhonghuajia against S. frugiperda, and ultimately enhanced the biological control efficiency. [ABSTRACT FROM AUTHOR]