Abstract
This study was conducted to induce cold-sensitive mutations in the Basc stock of Drosophila melanogaster and to identify the effective lethal phase (LP) and the temperature-sensitive period (TSP) for the mutants. Ethyl methanesulfonate (EMS) was used as the mutagenic agent. Basc EMS-treated males were mated to virgin Canton-S females. Progeny were mated individually and tested for lethality at 18 degree C and for viability at 25 degree C. The stable stocks obtained were retested for lethality at 18 degree C. Two different sex-linked recessive cold-sensitive lethal mutants were obtained out of 884 tested F1 males. The LP and TSP for both stocks were determined and described. Due to the variability and instability of cold-sensitive stocks, care should be taken in using such stocks.