ULTRASTRUCTURE OF GRAPEVINE (VITIS-VINIFERA) CHLOROPLASTS UNDER MG-DEFICIENCIES AND FE-DEFICIENCIES

In mesophyll chloroplasts of control plants of grape vine (Vitis vinif era L.) growing in greenhouse, grana consisted of 3-10 thylakoids inte rconnected by long stroma thylakoids. Chloroplasts in magnesium-defici ent plants were characterized by a dense stroma, poorly distinquished fine stroma lamellae, and by an accumulation of large osmiophilic glob ules. Under iron deficiency, the chloroplasts exerted two types of dam age of internal structure: (1) grana consisted of 2-6 thylakoids, the stroma lamellae were destructed; (2) grana were reduced, the stroma la melae were broken into short thick fragments, that were laid successiv ely in the direction along the axis of the chloroplasts.