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Life history and reproductive parameters of the mango red spider mite, Oligonychus mangiferus (Rahman and Sapra) (Acari: Tetranychidae) were studied to investigate its response to different temperatures (25, 28 and 31 ºC), with 70 ± 5% R.H. on Mangifera indica L. Baladi variety in the laboratory. The results showed that the developmental time of the individuals shortened with increasing temperature. The total immature stages was the longest period (7.51 day for the female and 7.46 day for the male) at 25 ºC, while at 31°C was the shortest period (6.48 and 6.46 day, respectively). The life cycle was the longest period (12.18 day for the female and 11.71 day for the male) at 25 ºC, while at 31°C was the shortest period (10.78 and 10.38 day, respectively). So, the mean generation time was the longest (20.12 days) at 25 °C, followed by 28 °C (19.06 days) and then at 31°C was the shortest (17.87 days). On the contrary, total fecundity was 32.50 eggs (2.05 eggs/♀/day) at 25 ºC, then at 28 °C it reached 30.17 eggs (2.01 eggs/♀/day) and 26.83 eggs (1.93 eggs/♀/day) at 31°C, respectively. The mean generation time recorded the shortest (17.87 days) at 31°C, while the fecundity recorded the highest rate at 25 ºC (32.50 eggs; 2.05 eggs/♀/day). Based on these results, we can predict the presence of O. mangiferus on mango. Therefore, it should be easily to determine the best time to control this pest.

The life history and predation rate of the predatory mite, Neoseiulus californicus (Mc-Gregor) on the citrus red mite, Panonychus citri (Mc-Gregor) were studied under laboratory conditions at 25°C and 60-70% R.H. All movable stages of the predator were able to devour all different stages of P. citri. Average consumption rates of eggs, larvae, protonymphs, deutonymphs and adult males and females of P. citri by the predator larva were 0.8 ±0.71, 0.7 ±0.32, 0.5 ±0.40, 0.3 ±0.23, 0.2 ±0.10 and 0.3 ±0.23 prey individuals, respectively. These values increased with predator development from protonymph to adult. The predator adult female devoured 7.8 ±1.12, 7.5 ±0.86, 5.0±1.30, 3.7 ±0.86, 2.5±3.20 and 5.1 ±0.86 prey individuals; while those for male were 5.5 ±0.72, 5.5 ±0.86, 4.3 ±1.40, 3.6 ±0.86, 3.0 ±2.4 and 4.0 ±0.86 prey individuals for the previous prey stages, respectively. Thus, the predator adult female ate more than any other stage. In addition, the eggs and larvae, compared to other stages of P. citri, were the most consumed by all different predator stages; this raised the predator fecundity unlike the adult stage of the prey. Predation rate, life cycle, and oviposition periods varied depending on prey stages. The intrinsic rate of natural increase (rm) was higher on prey immatures and eggs than on prey adult females, which were 0.149, 0.092 and 0.042, respectively. Results indicated the effectiveness of N. californicus as an important biological control agent against P. citri.

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