الفهرس 
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Abstract
The developmental times and rates of immature stages, growth index, survival percentage, longevity, fecundity and life table parameters of Rodolia cardinalis, Nephus includens and Chrysoperla carnea when reared on I. purchasi, I. aegyptiaca and I. seychellarum were studied at five constant temperatures (16, 20, 24, 28 and 32ºC). The relationship between developmental rate of each stage and tested temperatures was also regressed. 1. Rodolia cardinalis There were significant variations in total developmental time of immature stages of the predator were reared on the three studied preys. Meanwhile, there were significant variations among the three mealybug species at the same temperatures. Growth index and developmental rate of R. cardinalis were higher at 28ºC than at 32, 24, 20 and 16ºC when reared on the tested mealybug species. Survival percentage of immature stages when reared at 24ºC was higher (80.4%) on I. aegyptiaca than on I. purchasi (79.3%) and I. seychellarum (72.8%).Rodolia cardinalis required 256.41 DD’s to complete the development from egg stage to adult stage when reared on I. purchasi while it was 238.1 DD’s on I. aegyptiaca. Meanwhile when reared on I. seychellarum it was 312.5 DD’s. There were significant differences in pre-oviposition period, oviposition, inter-oviposition and total longevity when the predator was reared at the five tested temperatures. Male longevity was significantly shorter at 32ºC than at 28, 24, 20 and 16ºC, when fed on the same prey. Fecundity rate was significantly higher at 28ºC than at 24, 32, 20 and 16ºC when fed on the same prey. The mean generation time (T) and doubling time (DT) were shorter at 32ºC than at 28, 24, 20 and 16ºC when fed on the same prey. Generally the value of gross reproductive rate (GRR), the net reproductive rate (Rₒ) was higher at 24ºC than at 28, 20, 16 and 32ºC. The intrinsic rate of increase (rm), the finite rate of increase (λ) was higher at 28ºC than at 24, 32, 20 and 16ºC. 2. Chrysoperla carnea There were significant variations in total developmental time of immature stages of the predator were reared on the three studied preys. Meanwhile, there were significant variations among the three mealybug species at the same temperatures. Growth index and developmental rate of C. carnea were higher at 28ºC than at 24, 32, 20 and 16ºC when reared on the tested mealybug species. Survival percentage of immature stages when reared at 28ºC was higher (89.53%) on I. purchasi than on I. seychellarum (89.16%) and I. aegyptiaca (87.06%). Chrysoperla carnea required 384.62 DD’s to complete the development from egg stage to adult stage when reared on I. purchasi while it was 384.615 DD’s on I. aegyptiaca. Meanwhile when reared on I. seychellarum it was 400 DD’s. There were significant differences in pre-oviposition period, oviposition, inter-oviposition and total longevity when the predator was reared at the five tested temperatures. Male longevity was significantly shorter at 32ºC than at 16, 28, 20 and 24ºC, when fed on the same prey. Fecundity rate was significantly higher at 28ºC than at 24, 32, 16 and 20ºC when fed on the same prey. The mean generation time (T) and doubling time (DT) were shorter at 32ºC than at 28, 24, 20 and 16ºC when fed on the same prey. Generally the value of gross reproductive rate (GRR), the net reproductive rate (Rₒ), was higher at 28ºC than at 24, 20, 16 and 32ºC. The intrinsic rate of increase (rm), the finite rate of increase (λ) was higher at 28ºC than at 24, 32, 20 and 16ºC. 3. Nephus includens Developmental time and rate of immature stages, growth index, survival percentage, longevity, fecundity, and life table parameters of Nephus includens (Kirsch) were investigated when reared on the three mealybug species namely, Icerya purchasi, Icerya aegyptiaca, and Icerya seychellarum at 28ºC. There was no significant variation in the incubation periods for N. includens when the predator was reared on the three tested preys. ANOVA showed that there were no significant differences in 1st, 2nd, 3rd, and 4th instars larvae when the predator was reared on the three tested preys. The total developmental time of immature stages was 26.3, 25.9, and 28.2 days on the three tested preys, with significant differences. Growth index of N. includens was 2.8517, 2.9069, and 2.4823 on the three tested preys, respectively. Developmental rates of the total immature stages were 0.0380, 0.0388, and 0.0355 on the three tested preys, with no significant difference. Results indicated that the survival percentages of immature stages when reared on I. purchasi and I. aegyptiaca were higher than on I. seychellarum. There were no significant differences in pre-oviposition, oviposition, inter-oviposition and total longevity periods among the three tested preys. Male longevity was 61.33, 63.83, and 53.17 days with no significant difference among the three tested preys. Fecundity of females was 94.17, 122.17, and 50.67 with significant differences among the three tested preys. The mean generation time (T) was 41.66, 43.94, and 48.22 days, respectively when reared on the three tested preys. The population of this predator could be doubled every 76.30, 8.80, and 127.60 days on I. purchasi, I. aegyptiaca, and I. seychellarum at 28ºC. The values of gross reproductive rate (GRR) were 69.82, 57.52, and 31.86. Rₒ was 44.03, 31.94 and 13.73 when reared on the three tested preys. The intrinsic rate of increase (rm) was 0.0091, 0.0788, and 0.0054 when reared on I. purchasi, I. aegyptiaca, and I. seychellarum at 28ºC. The finite rate of increase (λ) was 1.0951, 1.0820, and 1.0558 on the three tested preys. The survivorship (Lx) for female age intervals was 64.0, 68.0, and 58.0 on the three tested preys, respectively.