Volume 24, Issue 6
December 1946, pages 247-278
pp 247-254 December 1946
pp 255-259 December 1946
The fungus causing powdery mildew of betel vines is described as a new species ofOidium. The symptoms of the disease, which is localised at Bassein and Kelva Mahim in Thana District of Bombay Province, are described. Powdery mildew can be easily checked by dusting betel vines with finely powdered sulphur.
pp 260-263 December 1946
The list of alternate host plants ofE. devastans given by Husain and Lal can now be revised in the light of present knowledge and is given below in order of the importance of the plant:—
Hibiscus esculentus (Bhindi).
Althea rosea (Hollyhock).
Solanum melongena (Brinjal).
Solanum tuberosum (Potato).
Hibiscus mutabilis (Changeable rose).
Helianthus annus (Sunflower).
Datura fastuosa (Gul dhatura).
pp 264-278 December 1946
The influence of xanthine, adenine, uric acid, theophylline, guanine, creaturine, oxalic acid, sodium diethyldithiocarbamate and 8-Hydroxy-quinolin on the oxidation of vitamin C by Cu and ascorbic acid oxidase has been studied.
Sodium diethyldithiocarbamate and 8-hydroxyquinolin inhibit both the enzymic and Cu oxidation of vitamin C. The other compounds investigated inhibit only the Cu oxidation without exerting any influence on the enzymic oxidation of the vitamin.
The bearing of these results on the nature of ascorbic acid oxidase and their application to the study of the nature of catalytic systems in plants which oxidise the vitamin have been discussed. Various types of inhibitors of vitamin C oxidation have been listed and properly classified.