Morphometric Characterization of Halophytic Plant Chloroplasts

Abstract

The data concerning morphometric characterization of chloroplasts belonging to two groups of halophytes distinguished by their salt tolerance—“highly salt-tolerant” (Climacoptera aralocaspica L., Salicornia europaea L., and Suaeda arcuata (Bange)) and “moderately salt-tolerant” (Kochia prostrata (Schrad) L. and K. scoparia L.)—are presented. Plants of the first and second groups were grown for 2.5 months at soil salinization within limits 0–1000 and 0–600 mmol Na⁺/dm³, respectively. Morphometric parameters (linear sizes, proportion of stromal inclusions of starch and plastoglobules) of mesophyll chloroplasts of two groups were maintained at a constant level within corresponding range of soil salinization practically coinciding with limit of their stable photosynthetic activity. Based on these results, it is suggested that chloroplasts provide energy and assimilates to the processes of ionic and water homeostasis realized at cellular and overcellular levels within the organism’s response norm and, thereby, contribute to forming the system response of a plant to soil salinization.