Department of Plant Sciences, King's College, 68, Half Moon Lane, London, S.E., 249JF, U.K.
* Present Address: Bangladesh Agricultural Research Council, Airport Road, Farm Gate, Dhaka-15 Bangladesh.
Complete Photoconversion of convertible protochlorophyll (ide) in etiolated bean primary leaf was studied with 1 ms flash from a Courtenary Sola—2 instrument. It was found that 1 ms flash failed to give complete photo-conversion when set at a safe distance of 30 cm from the leaf material at 24±1°C. Two successive flashes are saturating for total conversion in 6 days, 4 flashes in 8 days and 3—4 flashes for the older dark grown bean leaf. It may be deduced that the number of electronic flashes (1 ms) required for complete photoconversion Of the convertible protochlorophyll (ide) in bean primary leaf are age dependent.
