CHLOROPHYLL AND CAROTENE CONTENT OF EIGHTEEN TOBACCO VARIETIES

Abstract

Leaves of 7 dark and 11 burley tobacco vars. were analyzed for chlorophyll and carotene. When the pigment cones, were calculated on a leaf-area basis, the average chlorophyll cone, of the dark tobacco vars. was 107% larger than the average of the burley vars. and the carotene content was 87% greater. All dark vars. analyzed were higher in chlorophyll and carotene on this basis than any of the burley vars. On an oven-dry wt. basis, the av. chlorophyll content of the dark tobacco vars. was 53% greater than the av. of the burley vars., and the carotene content was 38% greater. There was some overlapping between dark and burley vars. when the carotene content was expressed on a wt. basis. About half of the differences in pigment cone, of the dark and burley tobaccos may be attributed to a difference in leaf thickness. The av. ratio, by wt., of total chlorophyll to carotene of all vars. studied was 19.75, which is very close to the ratio that one would expect if 9 molecules of chlorophyll a and 3 molecules of chlorophyll b were associated in the same protein group with 1 molecule of carotene.