An ultrastructural study of the mature chromoplasts of the tangerine tomato ( Lycopersicon esculentum var. ‘Golden Jubilee’)

Abstract

The ultrastructure of somewhat immature and mature chromoplasts of a tangerine tomato variety, Golden Jubilee, has been studied after glutaraldehydeosmium and potassium permanganate fixation. Chromolipid inclusions occurring in these chromoplasts include droplets, tablet- and rod-shaped crystals, and a heretofore undescribed spheroidal inclusion. Except for the droplets, all of these inclusions have a myelin figure substructure or framework. Some myelin figures apparently become only partially pigmented. Aggregations of droplets appear early in plastid maturation and remain until plastid senescence, whereas the crystals and spheroidal structures characterize only the more mature stages. Several types of vesicles are found in immature plastids. One is spherical in section and closely associated with the lamellar system of the plastid, e.g., stacked lamellae and grana-like lamellae. Another is a large irregular vesicle that is confluent with small pinocytotic-like vesicles around its periphery.