Structural differentiation of modified Kranz anatomy in Salsola komarovii has been examined employing TEM and SEM. Leaves of Salsola were composed of epidermis, chlorenchyma, water storage tissue, and vascular bundles. The study mainly focused on inner and outer chlorenchyma tissue. The inner chlorenchyma layer exhibited characteristics of bundle sheath cells (BS) and the outer chlorenchyma layer the mesophyll cells (MS) of a typical C-4 structure. Hence, they were referred to BS and MS. Cellular organelles were centripetally arranged in BS, while those in MS were peripherally displaced. Chloroplast dimorphism, when starch was present, was detected between BS and MS. BS chloroplasts lacked grana but showed agrana to rudimentary thylakoids with numerous large starch grains. Relatively more mitochondria and microbodies were found in BS, but no structural dimorphism was noticed. More protein bodies were discovered in MS chloroplasts. Compact BS cell walls were much thicker than thin MS cell wall neighboring huge intercellular spaces. Numerous and complex plasmodesmata were most frequently encountered in BS-MS interfaces, indicating active metabolite transport between the two cell types. The current findings mostly correspond to one of the C-4 subtypes, NADP-ME type, known in the C-4 species. It implies that such a spatial differentiation of BS and MS probably have the structural and functional advantages for an adaptation to the environment where they occur.

Key words: Modified Kranz anatomy, NADP-ME type, Salsola komarovii, Structural differentiation