Evaluation of the predatory efficiency of Orius Albidipennis Reuter for two prey species Myzus Persicae (Sulzer)‎ and Thrips tabaci Lind. on the carrot plant in laboratory

الملخص EN

The study aimed to investigate the effect of different densities of M.

persicae and T.

tabaci on the predatory ability of the predator O.

albidipennis and determine the preference for one of the two prey, in addition to assessing the in vitro predator's efficiency in reducing the number of aphids on the carrot plant.

The results indicated that the rates of predated adult and nymph thrips were significantly higher than that of predated aphids.

The highest rate of predation for nymphs and adults thrips was 33.2 and 25 preys per day, respectively, at a density of 60prey/container, while the highest rate of predation of adults and nymphs of aphids was 19 and 13.2prey/day, respectively, at a density of 60prey/container.

The food preference experiment showed that the adults of the predator O.

albidipennis feed on the immature stages thrips and aphids when introduced together and have no clear preference for one of the prey.

The results of evaluating the efficiency of predator adults on reducing different densities of aphids showed that the predator was effectively able to reduce the population increase of aphids when the insect densities were 10, 20 or 30 insect.

however, the predator was not effective when introduced to aphids at starting density of 40, no significant difference was found due to predator presence or ence as the aphids population density were 118.4 and 135.2 insects/cage after four days, respectively.