Cold Shock Response in Biological Traits of the Silkworm, Bombyx mori

Abstract

In response to the ambient temperature, insects' physiology and behaviour change just like those of all other living things. For this investigation, the FC1 X FC2 double hybrid silkworm strain/breed was used. The larvae were collected on the third day of their fifth instar and put in little paper trays for a one-hour cold shock treatment at 10, 15 and 20°C with a relative humidity of 75±5% in B. O. D. The CS-induced larvae were allowed to recuperate for an hour at room temperature. Compared to the control (2.16 g) of the FC1 X FC2 larvae, the average weight of the recorded larvae was 2.30, 2.31, and 2.2 g, which correspond to 10, 15, and 20°C, respectively. When compared to the control group, the population created from 10°C demonstrated an ERR improvement of 70.83 percent (67.50 percent). However, at 15°C and 20°C, respectively, an elevated ERR of 86.67 and 75.83 percent was noted. Mortality was 11.67% between 10 and 15°C, whereas it was 12.50% at 20°C. The ability to transition into the next instar, spin a cocoon, become a pupa and eventually become a moth was utilised to assess the cold's potential impact on larval, pupal, and adult mortality. Highest cocoon weight of 1.37 g was observed at 15°C. Weights of the cocoons were measured and compared to the control (1.30 g), which corresponds to temperatures of 10 and 20°C, respectively. The cocoons made by CS larvae at 10, 15, and 20°C and the control had shell weights of 0.22, 0.24, and 0.19 g, compared to 0.30 g for the control. Temperature of 15°Cshowed higher efficiency in all the traits studied whereas other temperatures showed a slight decline in all the traits. As a result, we inferred that FC1 X FC2 had exhibited a profound response to CS temperature of 15°C and can be used to develop CS silkworm strains for the temperate areas.