Diapause Termination of Eggs of Silkworm, Bombyx mori Using Hydrochloric Acid and its Effect on the Insect’s Biological Characteristics
I. Okasha1, A. Arab1* and H. Al-Roz2
(1) Latakia Agricultural Scientific Research Center, Buka, Syria; (2) Faculty of Agriculture, University of Damascus, Syria. *Email address of corresponding author: atiearab@hotmail.com
Received: 28/12/2022; Accepted: 19/6/2023
https://doi.org/10.22268/AJPP-001229
Abstract
The study was carried out in the summer and fall of 2022 at silkworm laboratory of the Latakia Agricultural Scientific Research Center to study the effectiveness of hydrochloride acid in preventing embryonic diapaus and eggs hatching of silkworm, Bombyx mori L., and its effects on the insect’s biological characteristics. The eggs were treated with hydrochloric acid solution during the summer breeding season, at 1, 12, 24, 36 and 48 hours after oviposition. The silkworm eggs were also treated in the fall season after cold storage for 45, 60 and 90 days at 5°C and 70-80% relative humidity. The results obtained showed that the highest hatchability rate was 96% when the eggs were treated at the age of 24 hours for 30 minutes. The results also showed that the highest effective rate of rearing (ERR) was 98.79% in eggs of 12 hours age. The highest average weight of the cocoon and shell was 1.64 and 0.33 g, respectively, when eggs were treated at the age of 1 hour for 30 min. Results also revealed that the effectiveness of hydrochloride acid in preventing diapause of stored eggs and the highest hatching rate was 95% of eggs stored for 90 days, and the ERR was 92.98%, 96.34% and 95.1% of eggs stored for 45, 60 and 90 days, respectively.
Keywords
Silkworm, eggs, hatchability, storage, hydrochloric acid.