NUTRITIONAL STUDIES WITH PSEUDOSARCOPHAGA AFFINIS (FALL.), A DIPTEROUS PARASITE OF THE SPRUCE BUD-WORM, CHORISTONEURA FUMIFERANA (CLEM.): III. EFFECTS OF NINETEEN AMINO ACIDS ON GROWTH
Feeding tests with the parasite Pseudosarcophaga affinis (Fall.) reared aseptically on chemically defined media showed that food lacking l-arginine, l-histidine, dl-isoleucine, l-leucine, l-lysine, dl-methionine, dl-phenylalanine, dl-threonine, dl-tryptophane, or dl-valine failed to support larval growth beyond the first instar. Omitting glycine from the diet lowered the rate of growth and permitted only a small number of individuals to develop beyond the first instar. There were statistically significant differences between the rates of growth on the control diets and on diets lacking dl-alanine, glycine, dl-serine, or l-tyrosine. When dl-aspartic acid, l-cysteine, l-glutamic acid, l-hydroxyproline, or l-proline was omitted from the food, larval growth and development were not affected.