Chloroplast ultrastructure in two Crassulacean species and an F₁ hybrid with differing biomass δ¹³C values

Abstract

The chloroplasts of two species of the Crassulaceae and their Fi hybrid were compared by electron microscopy. The two species had contrasting leaf tissue d^^C values of -25%^ {Sedum greggii) and -13%o (Cremnophila linguifolia), and the Fi hybrid had a value of -18%o. S. greggii had a mean of 8.9 thylakoids per granum in contrast to C. linguifolia which had a mean of only 3.8 thylakoids per granum. The Fl hybrid had a mean of 6.4 thylakoids per granum. Crystaloids were observed in S. greggii and the hybrid but not in C. linguifolia

Structure of the Leaf of Pyrossia Longifolia—a Fern Exhibiting Crassulacean Acid Metabolism

“…The average number ofthylakoids (5.8) per granum in the mesophyll chloroplasts of Pyrossia is similar to that found in the CAM species, Ferocactus acanthodes (x = 3.0-4.0; Thomson and Platt, 1973) and Cremnophila linguifolia (x = 3.8; Teeri and Overton, 1981).…”

“…These values are at the lower end of the range ofthylakoid numbers (typically 5-20) per granum for chloroplasts of all vascular plants examined (Kirk and Tilney-Bassett, 1978). Chloroplasts with reduced grana also occur in the bundle-sheath cells of NADP malic enzymetype C 4 species (Teeri and Overton, 1981). Interestingly, F. acanthodes and C. linguifolia belong to CAM families that are also classified as NADP malic enzyme-types (Osmond, 1978).…”

“…The few ultrastructural studies ofCAM species indicate that the typical photosynthetic cell in CAM plants is thinwalled with a narrow, peripheral band of cytoplasm surrounding a large, central vacuole (Willert and Kramer, 1972). Recently, Teeri and Overton (1981) found that in the chloroplasts of Cremnophila linguifolia, a CAM species with dark fixation ofatmospheric CO 2 , the number of thylakoids in grana is smaller than in the grana of chloroplasts of Sedum greggii, a C 3 species. Other· than this, little is known about the structure of CAM leaves.…”

“…The method for the determination of thylakoid number per grana was the same as that employed by Teeri and Overton (1981). Briefly, the number of electron-dense fusion lines within a granum was counted in every region of a chloroplast where the angle of the section was favorable.…”

Crassulacean Acid Metabolism in the Winter Annual Diamorpha cymosa (Crassulaceae) in Its Native Habitat

“…It has become clear that there are a number of different types of photosynthetic physiology among the species and genera of the Crassulaceae (Teeri 1982a, b). Common environment comparisons and a limited number of studies of the inheritance of photosynthetic phenotypes suggest that the differences are genetically determined (Knopf and Kluge 1979, Run del et al 1979, Teeri and Overton 1981.…”