VIRUS INFLUENCE ON PIGMENTS in DARK-GROWN AND LIGHT-GROWN PLANTS

Abstract

Three issues were Investigated; first, the influence of virus on pigment production in diseased plants; second, the increase of virus as indicated by a resulting change in carotene concentration; third, the function of pigments other than chlorophyll in photosynthesis in young potato leaves. Results on the first issue demonstrated an increase in carotene and xanthophyll concentration, and a decrease in chlorophyll concentration in diseased relative to normal plants. Evidence on the second issue suggests a close relationship between virus increase and. carotene concentration. Data on the third issue Indicated a small and possibly significant photosynthesis due to leaf carotenoids.