Isatis tinctoria var. yezoensis (Ohwi) Ohwi (Cruciferae) is one of major natural dyeing crops in the world and also have used as a medicinal plant in Korea. We evaluated seed purity in F1-hybrid accessions using amplified fragment length polymorphism (AFLP) markers. One hundred sixty seeds from the male and female harvests were subsequently screened for seed purity with ten primers. The 13 accession-specific bands and many variable AFLP bands scored for accessions. Especially, E-AAC/M-CAA and E-AAG/M-CAT were presented clear hybrid bands for F1 hybrids. F1 hybrids maintained higher average level of genetic diversity compared with their correspondent parents. Self-inbred seeds from the female and male harvests were revealed 8.0% and 5.0%, respectively. The AFLP may lead to a better insight in to the hybrid seed purity test in I. tinctoria var. yezoensis.

Methyl methanesulfonate (MMS) was fed to Drosophila melanogaster in order to investigate its toxic capability at developmental and adult stages, and the hereditary effect of toxicity and the potency for induction of sex-linked lethal mutation during the spermatogenesis by the means of an attached-X method. In the control group, the egg to adult viability of D. melanogaster was 95.2%, while 3.5mM and 5.0mM treated groups were 90.0% and 84.1%, respectively. In the case of their progenies (F_1), the viability was 96.9% in the control group, while 3.5mM and 5.0mM treated groups were 54.5% and 1.6%, respectively. Therefore, these differences between two generations show significant physiological toxic effects in the next generation. In the parental generation, the developmental time was calculated 11.05 days in the control group, 12.43 days in 3.5%mM treated group, and 13.23 days in 5.0mM. In the case of F_1 it was estimated 10.35 days in the control group, and 11.43 days in 3.5mM treated group. Compared with the control groups in two generations, the developmental time generally delayed as the dose of MMS increased. As to the sex-ratio, there was no differences between the control and MMS treated groups. The toxic values of adult stage showed which increased the frequency of mortality with MMS concentrations. The mortality at 120hr in the control group was 1.67% and it in 0.5mM MMS treated group 3.33%. In 2.5mM MMS treated group, it was 33.3% at 72hr, and it 95% at 120hr. The increase of the morality was shown from 72hr in 4.0mM treated group which was 100% at 96hr. There was the concentration-dependent induction of sex-linked lethal mutation during the spermatogenesis by means of an attached-X method, MMS had more pronounced effect in sperm and spermaid stages in D. melanogaster.