بعض الأوجة الحياتية و الكفاءة الافتراسية للمفترس Chilocorus bipustulatus (L.)‎ (Coleoptera : Coccinellidae)‎ على الحشرة القشرية Parlatoria blanchardi (Targ)‎ (Homoptera : Diaspididae)‎ على النخيل في المختبر

Abstract EN

Laboratory studies were conducted at the biological control unit, college of Agriculture, University of Baghdad to evaluate some biological aspects of the predator Chilocorus bipustulatus (Coleoptera: Coccinellidae), which is considered one of the most important predators on many insect pests, especially the scale insect, Parlatoria blanchardi, (Homoptera: Diaspididae) on date palms.

The results showed that biological parameters of the predator were varied according to different degree of temperature.

Egg incubation period was significantly different and reached to 7.5 and 5.44 day at 25 and 30°C respectively, Fertility was the same 100% at both temperature degrees.

Larval growth periods were 17.41 and 16.12 day as well as the mortality during this stage was also the same 0.0%.

Duration rate of pupal stage was 9.62 day at 25°C and reduced significantly to 7.13 day at 30°C.

No morality was found, in pupal stage at both temperatures.

The adult longevity rates for both males and females were also significantly different that the adult longevity of the male was 80.87 and 66.75 day and less than that of female longevity rate which reached to 90.89 and 67.0 days at both temperature degrees of 25 and 30°C, respectively.

Fecundity affected significantly and reached to 254.3 and 316.0 egg female at 25°C and 30°C, respectively.

The predator has very high consumption efficiency of scale insect nymphs, this predation was increased as the larva developed from one instar to the following.

As average the 1ˢͭ, 2ⁿᵈ, 3ͬ ͩ and 4ᵗͪ instars were consumed 95.12, 171.4, 328.06 and 710.0 scale insect nymphs, and the average of daily consumption of each instar reached to 23.78, 34.28, 65.61 and 140.2 nymph, respectively.

The average rate for the whole larval stage consumption was 263.87 and 1295.58.

The female of predator consumed more nymphs (127.5 nymph/ day) than that of male (106 nymphs/ day).