VIEW ARTICLE

Incorporation of ¹⁴C from Acetate and Mevalonate into Rishitin and Steroid Glycoalkaloids by Potato Tuber Slices Inoculated with Phytophthora infestans. M. Shih, Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907; J. Kuc, Department of Biochemistry, Purdue University, West Lafayette, Indiana 47907. Phytopathology 63:826-829. Accepted for publication 6 December 1972. DOI: 10.1094/Phyto-63-826.

The accumulation of steroid glycoalkaloids and rishitin in potato tubers after cutting or cutting and inoculation with Phytophthora infestans appears due to de novo synthesis via the acetate-mevalonate pathway. The branch point in the synthetic pathway which leads to rishitin or the steroid glycoalkaloids appears to be after mevalonate. Uninoculated slices incorporated more ¹⁴C from acetate and mevalonate into steroid glycoalkaloids than did slices inoculated with P. infestans. Slices inoculated with an incompatible race incorporated less isotope than those inoculated with a compatible race. Incorporation into rishitin was greatest with inoculated slices and most marked with slices inoculated with the incompatible race.