Biochemical Tests Indicative of Reaction of Castor Bean to Botrytis

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Science  25 Jan 1963:
Vol. 139, Issue 3552, pp. 334-335
DOI: 10.1126/science.139.3552.334


Pectic and cellulolytic enzymes caused browning and maceration of capsules of susceptible varieties of castor bean but not of resistant varieties. Results of tests in which pericarp tissue of the capsule was treated with vanillin and H2SO4 and with an aqueous solution of FeCl3 and K3Fe(CN)6 showed that resistance to the hydrolytic enzymes was correlated with both a low concentration of flavanols and related compounds and the presence of oxidized compounds in injured tissue. Resistance appeared to be due to inactivation of pectic, cellulolytic, and other hydrolytic enzymes by oxidation products of phenolic compounds. The biochemical tests made rapid measurement of resistance possible.