Anatomy of the Primary Axis of Solanum melongena

Abstract

1. In Solanum melongena, the primary meristems, calyptrogen, dermatogen, plerome, and periblem originating from the promeristem are not clearly differentiated. 2. The epidermis consists of one layer of cells from which root hairs arise; the cortex consists of six layers of parenchyma cells; and the endodermis and pericycle each consist of one layer. Lateral roots originate from the cells of the pericycle. 3. The stele of the primary root is a diarch, radial protostele. 4. Root-stem transition begins very low in the hypocotyl. The first change noted is a breaking up of the diarch xylem plate and the two primary phloem groups, forming two units of the primary xylem and phloem. At a higher level there is a bifurcation of the metaxylem and an inward differentiation of two of the phloem groups. 5. Near the cotyledonary plate there is a separation of the two double bundles formed by the breaking of the original diarch xylem plate. One of these double units becomes the vascular trace of one of the cotyledons, an...