Functional response and predation efficiency of the flower bug Orius albidipennis (Hemiptera : Anthocoridae)‎ to different densities of the cotton mealybug Phenacoccus solenopsis (Hemiptera : Pseudococcidae)‎ under laboratory conditions

Abstract EN

The cotton mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Sternorrhyncha: Coccoidea: Pseudococcidae) is considered a very dangerous pest of various vegetable crops in Egypt.

Also, the predator Orius albidipennis Reuter (Hemiptera: Anthocoridae) is one of the most effective control methods of many insect pests infested vegetables crops in Egypt.

This Study aimed to investigate the predation efficiency and functional response of O.

albidipennis to different densities of cotton mealybug P.

solenopsis (10, 15, 20, 25, 30 and 35) eggs, 1st and 2nd nymphal instars during 24 hrs.

period under laboratory conditions at 28 ±2 °C, 60 ± 5 % RH.

and L18:D6 photoperiod.

The results showed that O.

albidipennis preferred eggs compared with 1st and 2nd nymphal instars of the cotton mealybug.

O.

albidipennis good fitted to holling type II functional responses for each stage of this predator.

The increasing in prey densities lead to increase in the search efficiency (a), decreasing in handling time (Th) and increasing the predation efficiency of different stages of O.

albidipennis.

The handling time was shorter when fed on 2nd nymphal instar than the eggs and 1st nymphal instar (0.

026, 0.0128 and 0.00926 hrs.) for 4th, 5th and females of O.

albidipennis, respectively.

As well as, the rate of successful search (a) was higher when fed on 2nd nymphal instar than other stages (0.4841, 0.8318 and 1.1664 hrs.) for 4th, 5th nymphal instars and females of O.

albidipennis, respectively.

The maximum predation rate of females of predator was higher than the other stages (80.04 d-1) for eggs when compared with other stages of the cotton mealybug.

As well as, the females of this predator was consumed more eggs, 1st and 2nd nymphal instars of the cotton mealybug than 4th and 5th nymphal instars of the predator.

The mean numbers of consumed different stages of P.

solenopsis were increased by increasing prey densities.

So, we can use the females, 4th and 5th nymphal instars of O.

albidipennis in controlling eggs and small nymphal stages of the cotton mealybug in greenhouse or field on vegetables crops.