Biological Studies on the Cotton Mealybug Phenacoccus solenopsis Tinsley, (Hemiptera: Pseudococcidae) under the Laboratory Condition

Abstract

The cotton mealybug Phenacoccus solenopsis Tinsley (1989) (Hemiptera: Pseudococcidae) is one of the invasive species recently introduced to Egypt and nowadays it is wide spread among various parts of the country. The aim of this study shed light on certain biological aspects of the cotton mealybug and the effect of three host plant species i.e. (“potato”, “tomato” and “cotton”) as food source on certain biological aspects under the laboratory conditions. The results showed that the female and male of the cotton mealybug are not equal in numbers of moulting and nymphal duration. The life cycle of cotton mealybug was greater for males compared to females may be due to the additional moult and the pupal stage in the male, and it was significantly affected by different host plants, the females lasted 24.2±2.7, 22.1±3.1 and 20.0±2.7 days on potato, tomato and cotton plants leaves, respectively, while the males life cycle lasted 25.2±2.6, 22.9±3.1 and 21.4±2.9 days on potato, tomato and cotton plants leaves, respectively. Adult females lived longer than males, the female longevity lasted 31.2±2.5, 26.8±3.6 and 23.1±3.2 days on potato, tomato and cotton plants leaves, respectively, while males lived 3.1±1.3, 2.1±0.9 and 2.0±1.0 days on potato, tomato and cotton plants leaves, respectively. The cotton mealybug fecundity was significantly affected by different host plants; the females laid 163.3±48.5, 212.8±55.1 and 265.8±57.7 Eggs/female when adults reared on potato, tomato and cotton plants leaves, respectively. Sex ratio between females and males of P. solenopsis reared on potato, tomato and cotton plants leaves are not affected by the host plant. From the motioned results, it could be concluded that the cotton mealybug, P. solenopsis preferred cotton plant than the other two host plants. Key words: Cotton mealybug, Phenacoccus solenopsis, biological studies, Egypt.