Damage status and seasonal occurrence of the mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) on roselle plants

The Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae), known as the cotton mealybug, has been one of the most important pests attacking roselle plants (Hibiscus sabdariffa L.) in recent years. The current study was conducted in a private roselle field of Balady cultivar at Esna district, Luxor Governorate, South Egypt, during the two growing seasons (2022 and 2023) to monitor the incidence of the pest. It also evaluated the influence of weather conditions and plant growth stages on the abundance of P. solenopsis. The data suggests that around May 13th, roselle plants were infested by the mealybug individuals which are the 7th week after sowing and the 20th standard meteorological week. The infestation continued to fluctuate until the 43rd SMW (crop maturity) in both seasons. In addition, the general averages of P. solenopsis individuals during the second cropping season were higher than those in the first cropping season. In both seasons, P. solenopsis abundance increased steadily in roselle in July and August. The seasonality and population fluctuations of mealybugs in roselle were influenced by weather conditions and plant stages. These effects were highly significant, and the variables changed from season to season. Additionally, the explained variance coefficients for the two cropping seasons were 93.41% and 90.29%, respectively. The population of mealybugs in the field during both seasons was most influenced by the average daily minimum temperature. This study can help develop efficient pest control strategies to minimize mealybug infestations in roselle crops, leading to improved yield, economic benefits, and environmental sustainability.