(Boisduval). Eggs, larvae and protonymphs of T. cinnabarinus may be optimal food for C. picanus, which obtained survival rates of 100%, 97% and 93%, respectively, on them. The survival of P. persimilis was around 6.7% with diets based on eggs, larvae and protonymphs, showing a high mortality level by dehydration when fed with eggs. The time of the postembryonic development was signifi cantly shorter (p < 0.05) for C. picanus than for P. persimilis when they were fed with eggs, larvae and deutonymphs of T. cinnabarinus. When fed with eggs and a combination of different stages of T. cinnabarinus, the intrinsic rate of growth (r m ) was signifi cantly higher (p < 0.05) for C. picanus (0.289 and 0.307, respectively) than for P. persimilis (0.019 and 0.025, respectively). The values of the fi nite rate of growth (λ) were also signifi cantly (p < 0.05) higher for C. picanus (1.34 and 1.36) than for P. persimilis (1.02 and 1.03) when they were nourished with eggs and a mixed diet, respectively. The high values of r m and λ found for C. picanus in the experimental conditions are indicators of the possible control that this phytoseiid mite, as a predator of T. cinnabarinus, would potentially offer under the conditions of lower relative humidity encountered in the arid zone of the desert of Chile.

Abstract. Biological parameters of the woolly whitefly Aleurothrixus floccosus (Hemiptera: Aleyrodidae) and its parasitoid Cales noacki (Hymenoptera: Aphelinidae) were determined at 25.0 ± 2.0°C, 50.0 ± 10.0% RH and a photoperiod of 14L : 10D on three different Citrus host plants. The percentage survival of A. floccosus ranged between 40.23 and 44.44%. The highest mortality was recorded in the first nymphal instar with mortalities ranging between 36.36 and 39.39%. on C. aurantifolia the total development time was 39.83 ± 0.68 days and the pre-oviposition, oviposition and post-oviposition periods 2.45, 10.68 and 1.68 days, respectively. Adult longevity was 15.0 days and average fecundity 73.27 ± 9.07 eggs. For C. noacki the pre-oviposition period was 0.8 days, oviposition period 4.38 days and post-oviposition period < 1 day. Adult longevity of C. noacki was 5.18 days and average fecundity 31.25 ± 2.87 eggs. The intrinsic growth rate (r m ) of C. noacki (0.160) was significantly greater ( p < 0.05) than that of A. floccosus (0.076). The value of the finite rate of growth (λ) was also significantly ( p < 0.05) greater for C. noacki (1.173) than for A. floccosus (1.079). The larger values of r m and λ recorded for C. noacki under experimental conditions indicate that this aphelinid has the potential to decrease populations of A. floccosus.

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V. Tello, L. Díaz, and M. Sánchez. 2013. Side effects of the natural pesticide Spinosad (GF-120 Formulation) on Eretmocerus paulistus (Hymenoptera: Aphelinidae), a parasitoid of the whitefly Aleurothrixus floccosus (Hemiptera: Aleyrodidae), under laboratory conditions. Cien. Inv. Agr. 40(2):407-417. The side effects of the insecticide GF-120 NF 0.02 Naturalyte CB® were evaluated on adults of Eretmocerus paulistus Hempel, a parasitoid of Aleurothrixus floccosus (Maskell) in citrus orchards of northern Chile. LC 50 and LC 90 were determined by applying the insecticide using a Potter tower in decreasing doses from 0.96 to 0.1 mg a.i. L-1 (corresponding to 1% to 0.1% of the recommended dose, respectively). After 24 h of exposure, the results were fitted to a probit model, and the LC 50 and LC 90 were estimated at 0.21 and 0.79 mg a.i. L-1 , respectively. In feeding tests and evaluation of the toxic effect of dry residues of GF-120, it was determined that a high percentage of mortality (100%) was obtained using a combination of 24.0 mg a.i. L-1 x residues at 1 hour drying time. Residues at 96 h (4 days) drying time with concentrations of 38.4 or 24.0 mg a.i. L-1 caused mortalities over 60%. According to the classification of the IOBC (International Organization for Biological and Integrated Control of Noxious Animals and Plants) the manufacturer's recommended concentration of 96 mg a.i. L-1 was level 4, which is harmful (> 99%), as GF-120 concentrations can range from 0.77 to 72 mg a.i. L-1. The GF-120 residues applied on inert surfaces were harmful to E. paulistus with a high mortality rate under laboratory conditions. Field studies are needed to validate these results by evaluating parasitoid populations in insecticide-treated and untreated areas.

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