The developmental period of immature stages, survival per cent, longevity, fecundity and life table parameters of Harmonia axyridis by feeding on fresh and frozen grain moth eggs (GME) of Sitotroga cerealella were studied under laboratory conditions. The effect of crowding adults on fecundity of females was also determined. The total developmental time from egg hatching to adult eclosion ranged from 18.89 ± 0.32 to 22.5 ± 0.21 days on fresh and frozen GME, respectively. Survival per cent from egg hatching to adult emergence differed significantly when the predator fed on the two diets of GME. Also, pupal and adult weights were affected by feeding on fresh and frozen GME. There were no significant differences in longevity of females, while there were significant variations in fecundity of females and longevity of males. The calculated values of T, DT, Ro, rm, and erm were high by feeding on fresh GME. Morever, rates of survivorship (Lx), and maximum oviposition per female per day (Mx) were higher when the predator was reared on fresh than on frozen GME. Crowding conditions of predator adults affected the fecundity of females due to egg cannibalism by both males and females of the predator.

Five species of entomopathogenic fungi were tested against whiteflies and aphids. Cladosporium spp. showed a high incidence on the two insect species tested (81% of the total isolated species). However, C. uridenicola was the predominant species isolated from both insect species during the two successive seasons of 1998 and 1999. Natural infection by Cladosporium ranged from 18.19 to 44. 38% and 16.4 to 45.27% in 1998 and 1999, respectively, according to insect species and the host plant. Statistical analysis revealed a high correlation (R ¼ 0.8759 ± 0.093) between the total investigated and total infected of each insect species during the two successive years of the study. The natural infection of Cladosporium to whitefly life stages was higher on whitefly nymphs (87.8%) than adults (8.08%) and eggs (4.15%) in 1998 and 1999. The results showed that the seasonal distribution of Cladosporium occurred all year around, but rates were higher during the period from June until November which coincided with the high populations of whiteflies and aphids. The weather had a significant effect on infection of insects and had no effect on other fungi species. The laboratory tests showed a higher pathogenicity of the candidate on Aphis gossypii, Aphis craccivora and Bemisia agrentifollii than other reported fungi.

The drugstore beetle, Stegobium paniceum (L.) (Coleoptera: Anobiidae), is a pest of stored medicinal and aromatic plants. Generally, mortality of each stage increased with an increase of temperature and exposure time. Heat tolerance for different stages from highest to lowest was young larvae, old larvae, eggs, adult, and pupae. The mortality after 7 h at 42 degrees C for young larvae, old larvae, eggs, adults, and pupae, respectively, was 16 +/- 5, 31 +/- 6, 48 +/- 3, 63 +/- 8, and 86 +/- 2% (mean +/- SEM). Similar trends for stage specific mortality were seen with the lethal time for 90% mortality (LT90) at 42 degrees C; 773, 144, 12, and 11 h for old larvae, eggs, adults, and pupa respectively. Mortality was too low with young larvae to estimate LT90. The LT90 for young larvae at 42, 45, 50, 55, and 60 degrees C was 25, 20, 3.9, 0.18, and 0.08 h, respectively. The cold tolerance of different stages at 0 degree C from highest to lowest was adults, old larvae, young larvae, pupae, and eggs. The LT90 at 0 degrees C was 298, 153, 151, 89, and 53 h, respectively. The LT90 for adults at 5, -5, -10, and -15 degrees C was 792, 58, 2, and 0.8 h, respectively. The supercooling point of adults was -15.2 +/- 2 degrees C; young larvae, -9.0 +/- 0.8 degrees C; old larvae, -6.5 +/- 0.5 degrees C; and pupae, -4.0 +/- 1.4 degrees C. Heat treatments that control young larvae should control all other stages of S. paniceum. Cold treatments that control adults should control all other stages of S. paniceum. Dried plants stored at 5 degrees C for 45 d or 42 degrees C for 30 h and then kept below 18 degrees C throughout the rest of the year, should remain pest-free without any chemical control.

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Developmental stages of Coccinella undecimpunctata L. were stored at 6.0°C for various storage periods in a refrigerator. Egg hatching was 65.0% after 7 days of storage. However, no egg hatching were observed after 15, 30, 45 and 60 days of storage. The survival of the third and fourth instar larvae was higher than the first and second instar. The survival of larvae declined sharply after 15 days. No larvae survived after 30 or 60 days of storage. Emergence percentage of adults from stored pupae varied from 85.0 to 25.0% after storage for 7 up to 30 days. The survival percentage of adults differed and appeared to depend on prior feeding before storage. From the present results, it appears that the adult stage may be better able to survive extended periods of storage than the other developmental stages. In addition, it was found that prior feeding of adult stage affected the longevity, fecundity and consumption rate.

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