DIETARY ASCORBIC-ACID, PYRIDOXINE AND RIBOFLAVIN REDUCE THE LIGHT SENSITIVITY OF LARVAE AND PUPAE OF DROSOPHILA-MELANOGASTER

Drosophila melanogaster is light sensitive. On low yeast media, light induces high mortality during the development from egg to adulthood and increases development time. This effect of light is strongly dependent on the yeast-concentration. Addition of 8 vitamins, normally present in yeast, protects Drosophila against light under laboratory conditions. In this study we have analyzed the significance of the individual vitamins for both survival and development at high light intensities. Two D. melanogaster strains were utilized: a control strain C and a strain P. The latter had been adapted to a palmitic acid supplemented medium. In addition, we investigated the effect of vitamin C, a vitamin typically found in fruit, but not in yeast. It appears that both pyridoxine and riboflavin are essential for the survival of the control strain C under high light intensities, and they act synergistically. The other 6 tested vitamins can be omitted in these survival experiments. Moreover survival under high light conditions also improved strongly on media supplemented with vitamin C. The other strain (P), which was for many generations kept on a different food-medium, also was protected on yeast media by riboflavin and pyridoxine, and by vitamin C, although the survival at high light intensities on media with riboflavin and pyridoxine was less than the survival of the control strain.