Studies on the Leaf of Amaranthus retroflexus (Amaranthaceae): Chloroplast Polymorphism

Publisher Website
Google Scholar
Abstract
Seven ultrastructurally distinct types of chloroplast can be distinguished in the leaves of A. retroflexus L., each unique to a different cell type: vascular parenchyma, companion, bundle sheath, spongy parenchyma, palisade parenchyma, ordinary epidermal and guard cells. All chloroplasts contain grana and plastoglobuli and all may contain starch grains. The chloroplast types differ mainly in the degree of grana development and the nature and degree of development of peripheral membranes. Other differences occurring among chloroplast types include variations in starch and crystal content and in shape and size. The sieve-tube plastids, which lack grana, contain a ring of fibrous material typical of such plastids in the Caryophyllales.