Stem anatomical studies of two species of Talinum occurring in Southwest, Nigeria

Abstract

Taxonomic relationship using anatomical features of the stems ofTalinum triangulare (Jacq.) Willd and Talinum paniculatum(Jacq.) Gaertn. was investigated. Transverse Section, Tangential Longitudinal Section (TLS), and Radial Longitudinal Section (RLS) of mature stems of each of the species were cut at 8 - 15 µm with the aid of a Reichert sliding microtome. Stem cuttings of about 10 cm of each species were also macerated using 10% Sodium hydroxide solution. Sections and macerates were stored in 50% ethanol. Sections and macerates were stained and viewed under the microscope. The study showed that the species had similar stem anatomical features, indicating close affinity and being members of the same genus but could still be separated based onthe presence of brachysclereid, osteosclereid, and multiseriate rays randomly distributed in T. triangulare while T. paniculatum has more regularly arranged multiseriate rays with neither brachysclereids nor osteosclereids. The compound rays of T. paniculatum are thin walled but thick-walled in T. triangulare. The ray cells in T. triangulare are more or less similar, but in T. paniculatum, the ray cells reduce in size from the peripheral region to the centre.