STUDIES IN THE METABOLISM OF CRASSULACEAN PLANTS: DIURNAL VARIATION OF ORGANIC ACIDS AND STARCH IN EXCISED LEAVES OF BRYOPHYLLUM CALYCINUM.

摘要: It has been shown in a previous paper (7) that the diurnal variation of organic acid content excised leaves Bryophyllum calycinum cultured water under normal light conditions greenhouse is accompanied by starch opposite sense. The acidity decreased during day while increased, but increased night decreased. In terms quantity substances concerned, these two changes composition were far largest observed, and their relative magnitude was such as to lend color view metabolism acids closely connected with starch. observations thus supported hypothesis Bennet-Clark (1, 2) certain polysaccharides malic succulent plants this type are respective beginning end products series chemical equilibria, concentration components at any point time being function illumination which had previously exposed. Wolf (12, 13) have laid particular emphasis upon polysaccharide concerned case calycinum. experiment carried out laboratory limited study samples over period 24 hours. seemed desirable, therefore, repeat for longer order see what extent transformations would continue respond repeated alternations darkness. Furthermore, moderately accurate analytical method isocitric since become available, direct examination behavior component now possible. work, estimated difference, procedure might well introduce error into conclusions reached.