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The differences of bionomics and ecologies of the two populations of Callosobruchus chinensis on mung bean (Vigna radiatus) at six constant temperatures (20, 25, 28, 30, 32, 35°C) and 75% r. h. were researched. ANOVA showed that temperature affected the developmental period and fertility significantly (P < 0.05). T-test indicated there was significant difference of the combined immature stages between the two geographical populations at 25 and 32°C (P < 0.05). The average oviposition between the two geographical populations differed significantly at the same temperature (P < 0.05). At 30°C and 75% r. h., effects of 5 commercially grown legume seeds on development and reproduction of the two geographical populations of Callosobruchus chinensis (L.) were researched. The results showed that broad bean and soybean were more suitable for increase for Xichang population in terms of rm values. The adult weight and diameter of emergency hole of the two populations were also compared. According to the differences in the characteristics of development, reproduction, and damage to host seeds between the two geographical populations, conclusion can be drawn that both are different geographical populations.

Adults of the psocid Liposcelis bostrychophila Badonnel were exposed to atmospheres containing 35% and 55% CO2 for 30 generations to select strains resistant to high CO2 content (HCC). Selection pressure was maintained at around 70% of mortality. At the 30th generation, comparison of sensitivities between the selected strains (HCC1 and HCC2) and the original susceptible strain (MA-S) revealed a resistance factor (RF) at the 50% mortality level (LT50) of 4. 6-and 5. 3-folds, respectively. Throughout the selection process, log-time against probit-mortality lines remained roughly parallel and the slopes remained lower than that of MA-S strain until the last generation. It is inplied that the genetic potential of L. bostrychophila to develop resistance to CO2 was not exhausted until the 30th generation. Removal of selection pressure for 5 generations from 2 sub-populations of two selected strains from the 25th generation caused significant reduction in resistance. In the absence of MAs exposure, the two selected strains (HCC1 and HCC2) possessed the fitness defect. HCC1 and HCC2 were calculated by R0 to have a fitness value of 0. 52 and 0. 45 relative to MA-S.

This paper deals with the biological characteristics of the psocid Liposcelis entomophila (Enderlein) on a diet composed of whole wheat flour and yeast (10: 1) under different temperatures (17.5–35C) and relative humidities (50%-90% RH). The results showed that at 75% RH development time from egg to adult varied from 71. 9 d at 20% to 21.7 d at 35C. At 28C it varied from 23.0 d at 90% RH to 34.4 d at 60% RH. The development threshold and the effective accumulated temperature for entire immature stages were estimated at 15. 7C and 460. 7 day-degree, respectively. The survival rate from egg to adult was 64. 5% at 27. 5C while at 20C and 35C it was only 32.1% and 37. 0%, respectively. At 28C the survival rate ranged from 31. 2% at 60% RH to 67.8% at 80% RH. L. entomophila could not survive at any humidity at 17. 5C and below 50% RH. The average longevity of adult ranged from 32.4 d at 35C and 64.4 d at 20C. At 75% RH the mean egg production varied from 27.1 at 27. 5 C and 13. 9 at 20C and the greatest fecundity occurred at 90% RH with 28C. The optimal ranges of temperature and humidity for L. entomophila population growth were 27. 5–30C and 80%—90% RH. The distribution and the reason for its serious infestation in China are discussed.