LERER, M., Division of Citriculture, A.R.O, Volcani Center, P.O.B. 6, Bet Dagan, Israel
BAR‐AKIVA, A., Division of Citriculture, A.R.O, Volcani Center, P.O.B. 6, Bet Dagan, Israel

Manganese deficiency in chloroplasts of Eureka lemon leaves resulted in 23% and 40% increase of chloroplast nitrogen and protein, respectively, on a chlorophyll unit basis. Acrylamide gel electrophoresis carried out on extracts of these chloroplasts disclosed also qualitative differences between the normal and deficient leaves. Calculated on chloroplast N basis there is an increase of 17% in the chloroplast protein under Mn deficiency. This increase apparently indicates a more intense protein synthesis in the Mn deficient chloroplasts. Hill activity of the –Mn leaves was about one‐third of the analog control leaves. Manganese infiltration into detached but intact leaves restored the activity in the –Mn leaves up to 70% of the control. Lemon leaves affected by other macro‐ and micro‐ nutrient deficiencies did not respond to the manganese infiltration; therefore, the use of this infiltration method is suggested for the evaluation of the manganese nutrition status of citrus and probably other higher plants. Copyright © 1979, Wiley Blackwell. All rights reserved