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چکیده
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Habrobracon hebetor (say) is considered an essential biocontrol agent for various lepidopteran species such as Helicoverpa armigera (Hübner). In the present study, life table parameters of the parasitoid wasp and its population projection were estimated in a growth chamber at 25 ± 1 °C, 60 ± 5% RH, and photoperiod of 16:8 h (L:D) on H. armigera. The herbivore was reared using three cultivars, namely Earlyurbana, Superstrain-B, and Primoearly, as well as being treated with four nitrogen levels (0, 2100, 3000, and 3900 ppm N as Urea 46%). Observations were noted for the developmental time of immature stages, survival, fecundity and mortality of adult stages. Data analysis was carried out based on the age-stage two-sex life table theory by using the life table parameters and population projection. The shortest (10.88±0.11 d) and longest (12.83±0.11 d) preadult developmental times were observed on the host reared on Earlyurbana, and Superstrain-B with the highest and lowest N concentration, respectively. Also, the larval duration ranged from (2.63±0.05 d) to (3.77±0.04 d) on Superstrain-B and Earlyurbana with the highest and lowest N levels, respectively. Moreover, the highest fecundity was recorded (82.1±6.93) eggs per female on Superstrain-B with the highest N concentration, whereas the lowest one (47.0±5.70) eggs per female on Earlyurbana with the lowest N levels. Results illustrated that the net reproductive rate (R0), intrinsic rate (r) and finite rate (λ) were significantly higher than those reared on unfertilized cultivars. Therefore, the fertilized treatments were relatively favorable hosts for the parasitoid wasps than unfertilized treatments. Population projection based on the age-stage, two-sex life table indicated the wasps population could grow faster when reared on Superstrain-B than on Earlyurbana treatments. Using the bootstrap technique, indicated that the life tables constructed based on the 2.5th and 97.5th percentiles of (λ) and (R0) may characterize
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