ULTRASTRUCTURAL CHANGES IN CHLOROPLASTS OF PHASEOLUS VULGARIS DURING DEVELOPMENT UNDER CONDITIONS OF NUTRIENT DEFICIENCY

Abstract

Plants of Phaseolus vulgaris were grown for a period of 4 weeks in nutrient solutions deficient in S, Mg, K, N, P and Fe, and compared with controls growing in complete nutrient solutions. At weekly intervals, tissue from all leaf groups fully expanded at the time of sampling was prepared for examination under the electron microscope. It was possible to examine chloroplast ultrastructure, firstly, during leaf development under each of the nutrient deficient conditions and, secondly, to compare the chloroplasts of similar leaf groups produced under different deficiency conditions. Although distinctive chloroplast types could be associated with conditions of Mg, K, N and Fe deficiency, chloroplasts from S and P deficient plants were variable in appearance. The chloroplast patterns produced were found to be consistent in palisade parenchyma tissue but in spongy mesophyll tissue cells frequently appeared plasmolysed and chloroplasts varied considerably in appearance. Particularly in the spongy mesophyll distinctive crystalline configurations were found within the chloroplasts. Copyright © 1971, Wiley Blackwell. All rights reserved