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The flea beetle, Agasicles hygrophila Selman and Vogt, was introduced into China in 1987. For a more comprehensive understanding of the effect of elevated CO 2 concentration on the population dynamics, we collected the life table data of the flea beetle, A. hygrophila , at two different CO 2 concentration conditions, i.e., ambient (420 µl/liter) and elevated (750 µl/liter). The raw data were analyzed using the age-stage, two-sex life table theory. At 750 µl/liter CO 2 , shorter developmental durations of the egg, first instar, and pupa were observed, while the duration of the third instar and the total developmental duration of the larva were prolonged. The generation length of A. hygrophila was significantly shortened at the higher concentration. It was observed that the intrinsic rate of increase ( r ), finite rate (λ), and net reproduction rate ( R0 ) were higher and the mean generation time ( T ) was shorter at 750 µl/liter compared with that at 420 µl/liter. The bootstrap techniques were adopted to estimate the variances and standard errors of the developmental time, longevity, fecundity, and the population parameters. The bootstrap technique generated a normal distribution that was consistent with the central limit theorem and critical for following statistical analysis and comparison. Population projections based on age-stage, two-sex life tables could reveal the stage structure of A. hygrophila population and the leaf consumption capacity. Data collected in this study can potentially be used to evaluate the efficacy of A. hygrophila as a biological control agent of the alligator weed.

Insect neuropeptides (NPs) in the pyrokinin/pheromone biosynthesis-activating neuropeptide (PBAN) family are actively involved in many essential endocrine functions. These peptides are potential targets in the search for novel insect control agents. This is the first report on the cloning and sequence determination of Chlumetia transversa (Walker) PBAN (Ct-PBAN) using rapid amplification of cDNA ends. The open reading frame of Ct-PBAN was 588bp in length and encoded 195 amino acids, which were assembled into five putative neuropeptides (diapause hormone homolog, α-neuropeptide, β-neuropeptide, PBAN, and γ-neuropeptide). These peptides were amidated at C-terminus and shared the conserved pentapeptide motif FXPR (or K) L. Moreover, Ct-PBAN had high homology to PBANs in Helicoverpa zea (84.1%), Helicoverpa armigera (83.5%), Helicoverpa assulta (83%), and Heliothis virescens (82.6%). Phylogenetic analysis showed that Ct-PBAN was closely related to its orthologs in the family Noctuidae. In addition, real-time quantitative polymerase chain reaction assays showed that the expression of Ct-PBAN peaked in the female head and was also detected at high levels in 1-d-old adults. These results suggested that Ct-PBAN is associated with sex pheromone biosynthesis in female C. transversa and could be used for developing C. transversa control systems based on molecular techniques.

Two unit cells to 200 A thick ultrathin YBa2Cu3O7-δ films have been synthesized and their growth mechanism and physical properties have been studied. Atomic force microscopy showed that the films grow with both spiral and layer by layer modes and the screw dislocations appeared even in the 6 unit cells thick films. In the initial growth stages of the films, the strong dependence of Tc on the film thickness is discussed.