Biology and Behavior of Mulberry Silkworm (Bombyx mori) in Northern Iraq

Abstract

Domestic silk worms were reared in Iraq during the 1970s and 1980s of the last century, but unfortunately they completely disappeared after 1990 till now due to the unstable situations and economic problems. This study was aimed to revive the neglected valuable insect in Iraq after its absent for three decades, and obtaining a large number of silkworm eggs for continuous rearing and experiments in the next years. Bombyx mori (Bursa White; ‘Bursa Beyazi’) were imported from Sericulture Center in Bursa, Turkey. Incubated eggs were hatched into larvae 7.00 ± 1.00 days after incubation. Hatching percentage was 97.75%   ± 3.11. The durations of larval instars (1^st, 2^nd, 3^rd, 4^th, 5^th) were 3.60 ± 0.55, 3.75 ± 0.55, 5.12 ± 0.73, 5.98 ± 0.51, 7.72 ± 0.55 days respectively. The total larval period was 26.17   ±1.50.  mature larvae spent 46.00 ±   14.50 hours for spinning cocoons.  Weight of a single cocoon was 1.7 to 2.5 gm and the weight of the cocoon shell was 0.45 g. The pupal period lasted for 10 to 12 days. The completion of the cocoon spent 46.00 ± 14.50 hours. Adults were emerged after 10.60 ± 1.50 days. Adult male longevity was 115.00 ± 5.00 hours, while adult female longevity was 135.50   ± 7.50 hours. Fertilized female laid more than 500 eggs in the form of clusters and the average weight of these eggs per a single female was 250 ± 30.00 mg. Average weight of 4^th and 5^th instars larvae were 3.45 ± 0.90 g and 5.25 ± 1.25 g respectively. It can be concluded that successful rearing can be performed during April -May and September – October due to the moderate temperature in these months.