Effect of Temperature on Silkworm Moth (Bombyx mori L.) Development and Productivity

H. GREISS1 and N. PETKOV2
1 Agricultural Company Agromier, Eg-11211 Cairo, Egypt
2 Sericultural Experimental Station, BG-3000 Vratza, Bulgaria

Abstract

GREISS, H. and N. PETKOV, 2001. Effect of temperature on silkworm moth (Bombyx mori L.) development and productivity. Bulg. J. Agric. Sci., 7: 471-474

The effect of three different temperature regimes for rearing of larvae of 11 monobivoltine silkworm moth races, namely 23 °C and 27 °C air temperature during the whole larval stage and 23 °C during the first three instars and 27 °C during the last two instars was studied.
The temperature regime for rearing of white-cocoon monobivoltine silkworm moth races and hybrids (27 °C during the first two instars, 25 °C during the third and 23 °C during the last two instars of larvae), applied in Bulgaria, was used as control.
It was established that rearing of larvae of monobivoltine silkworm moth races during the whole larval stage at a stable air temperature of 23 °C in the rooms leads to the increase of values of basic productive indexes such as cocoon weight, cocoon shell weight and raw cocoon yield per one box (20.000 ± 200 viable eggs) by 0.063-0.135 g (2.99-6.14%), 0.012-0.035 g (2.79-7.04%) and 1.17-2.50 kg (3.02-6.16%), respectively, compared to the temperature regime, currently applied in Bulgaria.
The new temperature regime of larval rearing also results in the reduction of premises heating costs due to the lower air temperature during the first three instars by 2-4 °C.

Key words: silkworm moth, cocoon, cocoon shell, cocoon shell ratio