The fungicide captan reduces nuclear DNA content in maize seedlings

Captan, a major fungicide used by the US maize industry, was studied to determine its effect on the nuclear DNA content of maize (Zea mays L.) seedlings. Captan was applied to kernels at the recommended agronomic rates. The nuclear DNA content of the seedlings was determined by flow cytometry. In two maize hybrids examined, a reduction in nuclear DNA content was observed. Two different fluorochromes, with different staining mechanisms, were used to determine nuclear DNA content. Both of these fluorochromes revealed a reduction in nuclear DNA. Captan is reported to inhibit DNA synthesis in several animal systems. The reduction of maize nuclear DNA observed in this study may be a result of DNA synthesis inhibition induced by captan.