Testing of the Gene Bank Silkworm Moth Races for Parthenogenetic Development Predisposition

Y. B. VASSILEVA and P. I. TZENOV
Sericultural Experiment Station, BG-3000, Vratza, Bulgaria

Abstract

VASSILEVA, Y. B. and P. I. TZENOV, 2001. Testing of the gene bank silkworm moth races for parthenogenetic development predisposition. Bulg. J. Agric. Sci., 7: 475-478

The testing for predisposition to ameiotic parthenogenetic development was done by means of a control and two experimental variants:
– control variant – non-fertilized eggs laid in natural temperature (24-25 °C);
– first experimental variant – eggs taken out of the ovarioles of non-fertilized female moths by dipping in water of 46 °C and 18 min exposure;
– second experimental variant – eggs laid by non-fertilized female moths were treated on the fourth day after laying by combined influence of low temperature (-10 °C) and water bath of high temperature (46 °C).
Comparing the control variant with the two experimental ones, the highest pigmentation percentage was obtained in the second variant, followed by the first one, the control being last. In terms of fully pigmented eggs, the first variant maintained the highest values, followed by the second and the control was last again. Hatchability of pigmented eggs had the highest values and was complete in the first variant. The second variant had lower values of hatchability, some races having none at all. The race Tahvon 106 was an exception and showed hatchability of 22.41%.

Key words: ameiotic parthenogenesis, temperature, race, silkworm moth