[Sublethal effects of fenpropathrin and avermectin on Panonychus citri (Acari: Tereanychidae).].

A leaf disc bioassay was employed to examine the effects of fenpropathrin and avermectin with a sublethal concentration of LC on the development and reproduction of F, F and F generations by means of life tables. The results showed that after the treatment of fenpropathrin at the sublethal concentration, the number of eggs laid per female significantly increased in F generation, the pre-oviposition duration was significantly shortened and the female ratio of offspring significantly increased both in F and F generations. The intrinsic rate of increase (r) and finite rate of increase (λ) values all increased, and the generation time (T) and population doubling time (Dt) were shortened in F and F generations, with significant difference observed between F generations and the control.

Effects of juvenile hormone analogue and ecdysteroid on adult eclosion of the fruit fly Bactrocera minax (Diptera: Tephritidae).

The univoltine Bactrocera minax (Enderlein) is a devastating pest of citrus in Nepal, India, Bhutan, and China. To better understand the overwintering pupal diapause, we investigated the juvenile hormone III (JH III) and ecdysteroid 20-hydroxyecdysone (20E) titers across the developmental stages, and the effects of juvenile hormone analog (JHA) and 20E treatments on adult emergence patterns. The results showed that both JH III and 20E levels fluctuated from the late larval stage to the late pupal stage.

Population forecasting model of Nilaparvata lugens and Sogatella furcifera (Homoptera: Delphacidae) based on Markov chain theory.

Nilaparvata lugens (Stål) and Sogatella furcifera (Horváth) are the two most important long-distance migratory insect pests that cause great yield losses to rice in China. Accurate long-term population forecast is needed to implement effective management strategies for these two rice pests. In this paper, a transition probability matrix of 5-yr steps of Markov chain theory was constructed based on 31-yr light-trapping data of the two pests from 1977 to 2007 in Jiangkou County, Guizhou, China.

[Resistance realized heritability and risk assessment of Panonychus citri to avermectin and fenpropathrin].

On the basis of resistance breeding and selection in laboratory, and by using the threshold trait analysis in quantitative genetics, this paper studied the realized resistance heritability of Panonychus citri (McGregor) collected from Beibei of Chongqing to avermectin and fenpropathrin, and predicted the resistance risk of P. citri to these two acaricides. After 11- and 16-generations of selection with avermectin and fenpropathrin, the resistance of P.

[Relative fitness of Tetranychus cinnabarinus resistant strains at different temperatures].

Based on resistance selection, the life tables of abameetin-resistant (AbR), fenpropathrin-resistant (FeR), and susceptible (S) strains of Tetranychus cinnabarinus at 15 degrees C, 20 degrees C, 25 C, 28 degrees C, 31 degrees C, 34 degrees C, and 36 degrees C were constructed, and the development duration, fertility, and intrinsic rate of increase (r(m)) of the strains were compared, aimed to understand the relative fitness of T. cinnabarinus resistant strains at different temperatures. The results indicated that compared with S strain, AbR and FeR strains had longer development duration at 15 degrees C but lower fertility at 20 degrees C-28 degrees C, and their relative fitness (represented by r(m)) was smaller at 15 degrees C but similar at 20 degrees C - 31 degrees C.

Infection by Wolbachia bacteria and its influence on the reproduction of the stored-product psocid, Liposcelis tricolor.

Wolbachia are maternally inherited intracellular bacteria that infect a wide range of arthropods and nematodes and are associated with various reproductive abnormalities in their hosts. The infection by Wolbachia of the psocid, Liposcelis tricolor (Psocoptera: Liposcelididae), was investigated using long PCR amplification of the wsp gene that codes for a Wolbachia surface protein. The results showed that L.

Influence of long-term exposure to simulated acid rain on development, reproduction and acaricide susceptibility of the carmine spider mite, Tetranychus cinnabarinus.

Development, reproduction and acaricide susceptibility of Tetranychus cinnabarinus (Boisduvals) (Acari: Tetranychidae) were investigated after long-term (about 40 generations) exposure to various levels of acid rain; pH 2.5, 3.0, 4.

The effect of the insecticide dichlorvos on esterase activity extracted from the psocids, Liposcelis bostrychophila and L. entomophila.

The inhibition kinetics of dichlorvos on carboxylesterase and acetylcholinesterase (AChE) activity extracted from Liposcelis bostrychophila and L. entomophila (Psocoptera: Liposcelididae) were compared. The results showed that L.