• Korean journal of applied entomology
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• v.51 no.3
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• pp.207-213
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• 2012

The cryptic mealybug, Pseudococcus cryptus, has been increasingly damaging citrus, particularly those plants grown in plastic greenhouses. This study was conducted to monitor the seasonal phenology of adult male cryptic mealybugs and to determine the timing for control using a sex pheromone trap. Adult males responded to a synthetic sex pheromone and trap color. An increasing number of males were attracted to the traps with increasing concentrations of sex pheromone up to 5 mg. The males occurred annually four times and had three cohorts at a time due to different overwintering developmental stages. After overwintering the adult males began to in mid-late April. A positive correlation was observed between the number of adult males caught in traps and the mean density per twig of all motile stages except first stage nymphs of the cryptic mealybugs. The peak time for the first nymph to occur was estimated from the maximum attraction time of the males, and the cumulative degree days (DD) was 350 DD, similar with the preoviposition period.

• The Korean Journal of Pesticide Science
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• v.5 no.1
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• pp.55-60
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• 2001

The efficacy of petroleum spray oil (PSO; D-C Tron $Plus^{(R)}$) against spirea aphid (Aphis citricola) and two scales (lcerya purchasi and Planococcus cryptus) on citrus was tested in Jeju, Korea. The control value of 0.33% PSO against spirea aphid was over 90% at 3 and 6 days after treatment (DAT), and then decreased to about 80% at 9 and 14 DAT. Spraying of PSO (0.33, 0.66, 1%) against cottony-cushion scale showed a much lower control value (less than 50%) during the investigation period compared to that of the conventional pesticide (Methion). When used against tile scale, Planococcus cryptus, the control value of 1% PSO was 95%, but that of 0.33% and 0.66% PSO only ranged from 50 to 80%, lower than the conventional pesticide. The results of this study, as with a previous study, suggest that spraying of 0.33% and 0.5% PSO not only controls the spirea aphid, but also reduces the density of two scales (lcerya purchasi and Planococcus cryptus) on citrus tree in Jeju, without phytotoxic damage.